Sheep’s Wool Insulation: The Energy Efficiency Podcast – episode 11

Sheep’s Wool Insulation

Herdwicks in the Lake District

Welcome to Sheep’s Wool Insulation: The Energy Efficiency Podcast – episode 11, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.

This week: grants for energy efficiency works – what’s available to help you make your home cosy for winter? Sheep’s wool insulation – the whys and wherefores, and energy efficiency in business – how to improve your offering while saving money.

wind powerPower failure

But before we get on with our advertised features, at the end of last week parts of the UK experienced a total power failure. As well as homes left without power, hospitals, airports, trains and traffic lights were affected.

The lights went out because two power stations failed within minutes of each other. One was a gas plant, the other a wind farm, which together produce 5% of our electricity. This was grist to the mill of those who oppose wind farms, but the problem was not, as has been reported by some outlets, that there was “too much wind” or indeed its opposite, not enough wind. The gas powered plant shut down in response to a technical issue. Automatic systems reduced power output significantly at the wind farm.

Part of the issue is that the National Grid is not prepared for power failure on this scale. However, safety systems operated as they should have. Power services to the vast majority of the country were maintained. These safety systems will come under review as part of an investigation into the causes of the blackout. Until it reports back there’s nothing to be gained by speculating on the causes of the blackout, although the National Grid has already ruled out a cyber attack.

Swift reconnection

The power outage had so much impact as it happened at rush hour on a Friday in August, but many of those affected were reconnected within 15 minutes. A power failure on this scale hasn’t happened in over a decade. The National Grid CEO pointed out that the UK has “statistically one of the most reliable energy networks not only in Europe but anywhere in the world.”.

He puts this down to massive investment from the energy industry in distribution and transmission networks over the last 30 years. Despite this, the National Grid could face a fine for a power outage on this scale.

Grants for energy efficiency works

We’ve mentioned grants a couple of times in past episodes, so we thought it was time to look at the detail. What can you, as a householder, access to improve the energy efficiency of your home? It depends on where you live and your circumstances. Many local authorities and groups run their own funding systems. Eligibility can depend on age, status as a homeowner, private tenant etc, and income.


Identifying precisely what any given household might be eligible for can be complex. For example, in Scotland loans of nearly £40,000 are available to owner-occupiers and private landlords for all sorts of improvement works including connection to a district heating network. Those struggling to pay for heating their home can access the Home Energy Efficiency Programmes for Scotland and the Warmer Homes Scotland Scheme. There’s support for tenants, and for people installing renewables. describes the system as complicated and suggests contacting the Energy Savings Trust’s partners to check eligibility.

Park homes

The Warm Home Discount scheme is run by the government. Strictly speaking it isn’t for home improvements, but is a discount on your electricity bill between September and March. If your electricity supplier also provides you with gas you can get a discount on your gas bill instead. The scheme ran last year and opens to new applicants in October 2019. To qualify you need to be receiving the Guarantee Credit element of Pension Credit, or if you’re on a low income and meet your energy supplier’s criteria for the scheme. It applies to pre-payment meters as well as billed customers. If you live in a park home the system operates differently and you’ll need to download a form from the government website.


The energy suppliers have an obligation to help those in certain population groups through the Energy Company Obligations (ECO) scheme. If suppliers fail to reach these groups they face fines, so there’s an incentive to offer freebies. Currently offers are in place under ECO3, which lasts until spring 2022. The focus of ECO is insulation but can include double glazing and solar panels. Under ECO3, local authorities can use “ECO Flexible Eligibility” to set their own criteria for eligibility for funding.

Boilers and insulation

Offers can take the form of boilers and insulation. It tends to be available to people on certain benefits and on incomes of less than about £16,000. Boiler grants tend not to be available to housing association or council tenants. Contact your energy provider to check eligibility. Again approach your energy provider about cavity wall insulation. E.on, EDF and Npower all run insulation schemes. EDF allows 10 weeks to complete works, which from today takes us to late October, so start that ball rolling if you think you’re eligible. Be aware that cavity wall insulation isn’t suitable for all properties so be sure to look into the specifics for your house. Note too that some suppliers might charge for erecting scaffolding, or removing old insulation. Money Saving Expert.

The Affordable Warmth Obligation is part of the ECO. It operates in England, Scotland and Northern Ireland to provide assistance to improve the energy efficiency of a home. In Wales a similar scheme called Nest is run by British Gas. Again the focus is boilers and insulation although in some cases it could involve an entirely new central heating system. This scheme is open to private tenants or home-owners on benefits, and social tenants in homes with an energy efficiency rating of E, F or G.


Locally, many services are available that help residents identify grants they might be eligible for. Support is available to wade through complex applications processes. These schemes usually offer energy saving advice as well, and help with dealing with fuel poverty and bill arrears.

Peel Square, Barnsley

Some schemes offer help on the basis of health needs. Since March this year Better Homes Barnsley will work with Warm Homes and Hospital Discharge Team to assess eligibility. Residents benefitting from this programme will be able to access the Barnsley energy tariff. This is a local offer from Great North Energy.

Agencies working together like this should mean those with the greatest medical needs will be in warm and affordable energy efficient homes. Generally referrals will come from health professionals and council workers, but people can self-refer. Barnsley has about 11,500 households in fuel poverty and above average rates of excess winter deaths. The scheme is funded by surplus from Berneslai Homes, the council’s housing company.

So it looks like the main source of potential funding for the average householder is through ECO3. Eligibility is complex and usually benefits-related, so you need to contact your energy provider to look at the details. If you’re planning on having cavity wall insulation check that your house is suitable. If you need advice on what’s available or help sorting out bill problems, your local authority is likely to run an advice and referral service.

Sheep’s Wool Insulation

I wonder how many of the households applying for the schemes we’ve just looked at will be offered sheep’s wool insulation? We looked at this in our feature on energy efficiency in self build in episode 5.

A timber-framed house

We learnt that sheep’s wool is not only insulating but provides a sound baffle and acts as a moisture buffer. It can absorb up to 25% of its own weight before thermal efficiency is affected. In a timber-framed house this can protect the frame from damage. In the damp UK this is a significant consideration. Wool has an insulation value unmatched by any other material, according to the website, which provides sheep’s wool insulation to the building industry. Sheep’s wool insulation has been used in one form or another for generations.

Prices for sheep’s fleeces, the raw material, have been very low in recent years, so given the work involved in processing and marketing them they just haven’t been really valued. This is changing now, with wool being promoted for insulation but also for all sorts of other products including duvets and coffins.

Environmentally-conscious choice

Sheared sheep

Sheep’s wool sounds a good option for the environmentally conscious all round. The sheep would be shorn anyway and don’t suffer. It takes less energy to produce sheep’s wool insulation than other types, and some projects use locally-sourced wool to keep the miles down.

What is it about sheep’s wool? It’s its naturally wavy structure. This traps loads and loads of air bubbles, which is what reduces heat and sound moving through. Not only does it keep you warm in the winter, but it keeps you cool in the summer.

Sheep’s wool insulation can be used like regular insulation. It comes in all sorts of shapes and sizes and rools and slabs. You don’t need to take precautions fitting it as it doesn’t irritate the skin like other forms of insulation. It traps pollutants and chemicals in the air, so as air passes into your home it’s purified.

The process

Scoured wool

Producing insulation takes just a few steps. First the wool is sorted into colours by the farmer. White fetches a higher price as it can be dyed more easily. The wool is then packed into bales containing over 400kg of wool. This minimises the cost and energy of transportation to the washing plant. At the washing – or scouring – plant the wool is blended to particular specifications. It’s then washed to remove all dirt, grass and so on and lanolin. The resulting raw fibre is covered with something called Ionic Protect.

Once the wool’s dry it’s carded to get all the fibres running in the same direction. Fibres are layered to get the required thickness. These are mechanically bonded. Lastly the rolls are wound and packaged.

Some types are mixed with polyester fibres. If you want a 100% natural product shop around and make sure any product you’re considering meets fire regulations. You can use sheep’s wool alone or combined with other products, and fit it anywhere in the house.

Is wool flammable?

Another of sheep’s wool’s benefits is that it has a high ignition temperature. If that temperature is reached, the wool with only char. Even this can be improved by adding a little Borax.

Thermal conductivity is measured in Watts per meter-Kelvin or k-value. Sheep’s wool has a thermal conductivity of between 0.035 – 0.04 W/mK, where as typical mineral wool has a thermal conductivity of 0.044 W/mK . That makes sheep’s wool about 10 times better at insulation. You will pay a bit of a premium for sheep’s wool insulation but it’s worth it.

Energy efficiency in business

In our features on energy efficiency in its many forms and across sectors, it’s come up again and again that businesses can reap serious benefits from improving energy efficiency. Leisure venues have improved the customer experience by saving money. In health more patients can be seen in a smaller building. In education students can learn in much more comfortable surroundings as settings shut down older, less efficient and more expensive-to-run buildings.

Government advice

The government estimates that an SME can reduce its energy bill by up to a quarter with payback of under two years by installing energy efficiency measures. It reckons 40% of these savings would require zero capital cost. The government has produced a PDF download to advise SMEs on energy efficiency. We’re taking most of our case study references from that PDF. It’s interesting and comprehensive so why not follow the link, download it, and read it on the train home?

Mark Carney

Recently Mark Carney, Governer of the Bank of England, warned that companies that fail to adapt to climate change will simply go out of business. He also noted that a great deal of money would be made along the way. At the same time the CBI has complained that government isn’t doing enough to encourage businesses to be more sustainable.

You run a business, you want to save money and energy, where do you start?

Of course this depends on the type of business you run, the size and reach of your operation and so on. Just as for domestic energy efficiency works, there are grants available. West of England Green Business Grants helps SMEs improve energy efficiency with cashback grants to cover up to 40% of eligible costs. Free energy surveys are also available. These works focus on improving the energy efficiency of a building. That covers lighting, insulation, heating and windows. Money is available too for acquiring more energy efficient equipment.

In our feature on energy efficiency in leisure this came up a few times. Replacing inefficient air conditioning unit increased visitor comfort, saved money and allowed for closer control of the temperature. There is always an environmental footprint to pulling out old equipment, but if old kit is very problematic or has reached the end of its useful life, upgrading with a much more efficient alternative will reap benefits.

Consuming far less energy doesn’t just keep bills down in the short term; it helps to protect companies against energy price rises in future. Newer more efficient kit should require less maintenance, suffer less downtime (which means less hassle) and serve your business for many years.

Fix problems

If you don’t want or need to replace an entire system or machine, check plant for any problems. A small printing machine manufacturer identified nine leaks in its compressed air system. By fixing them it’s saving well over £1000 a year and reducing its carbon footprint by 7 tonnes. Could you extract more from your current set-up? A vehicle repair and maintenace firm recovered heat from a compressor to warm its painting bay in winter. It saved nearly £1000 and 3.7 tonnes of CO2.


In that feature we also looked at heating bills. As in a leisure centre, most businesses could turn the heating down and reduce the time it’s on without staff or visitors noticing. Team that with improving insulation and glazing in a premises. Office layout can affect how warm people feel. Take a good look at how heating systems work and where heat is delivered in your building, and look at what can be done to make improvements, including if necessary moving the thermostat. Thermostats in the wrong place are responsible for an awful lot of unnecessary boiler uptime. The Chinese Contemporary Arts Centre in Manchester fitted a £100 timer and is saving nearly £4,500 per year and keeping over 17 tonnes of CO2 out of the atmosphere.

The PR case

There’s also a PR case for improving energy efficiency, both within and without your company. A prospective employee will usually be more attracted to a warm and well-functioning workplace than its draughty, clunky alternative. You’re more likely to attract the best staff, hang on to the them and see them take fewer sick days. To the outside world your business looks like it understands what’s going on in the world and cares about it. You might win more contracts.

Generating energy

Tilburg at night

If you have appropriate roof space, why not fit solar panels? In our recent feature on solar power we learnt that fitting PV panels to commercial buildings in the often cloudy and wet UK alone would produce at least 60% of the energy used by business. In the Netherlands a logistics warehouse in Tilburg sports 13000 solar panels on its roof. They produce enough power for all the operations at that site (just one of a whopping 660 owned by the parent company Rhenus, a logistics firm) but also powers about 750 homes from the excess power it generates.

The building currently holds the highest-ever BREEAM rating for an industrial building. The building is airtight and uses electric heating boilers only about 10 days a year, in the very coldest weather. Enormous windows let in lots of natural light which has reduced energy use for lighting by 70%. This building pays attention to detail. Rainwater is collected on the roof and used to flush loos. With over 30000 employees worldwide that sort of measure could make quite a difference. Imagine doing that in rainy Britain? In fact, why don’t we?

Alphons van Erven, senior VP of Rhenus, believes that eventually all companies will be forced by government to use these sorts of methods. Perhaps this is what the CBI had in mind? If governments worldwide charge companies for their carbon footprint, then the business already achieveing net zero won’t face these costs. However, works that increase the value of a business setting will also increase its business rates. The CBI wants to see government addressing this type of issue.


It’s not just heating and lighting costs businesses face. Transport is a biggie for many businesses. In Scotland, interest-free loans of up to £120,000 are available to help Scottish businesses lower their transport and travel costs by using low carbon alternatives. These loans cover electric and hybrid vehicles including HGVs and motorbikes and scooters, and telematics systems. Interestingly it also covers video-conferencing costs. It’s going to be vital to rethink how we communicate and when we really need to travel, as well as considering how to do it in a less carbon-heavy way.

Some change in habits and employee education or training makes a big difference to the success of energy efficiency measures. This is particularly so if a premises makes big changes and if many staff have been in place for quite a while. Making a big point of including staff in consultation and decision-making will have a sizeable effect on the success of the measures any firm takes.

Small measures

Small measures make a difference too. An engineering firm set up a Switch Off campaign to make sure all staff turned off computers at the end of the day and at weekends. It saved £600 a year and 3.5 tonnes of CO2. That’s a perfect no-cost money saving move. Staff leisure facilities should be looked at too. Kitchens are an area where savings can be made through encouraging good habits and making sure equipment is energy efficienct, used sensibly, and well-maintained. A market reserch company, DJS Research, has used timer switches to turn off its water coolers at the weekend. It’s saving nearly £150 a year and the devices paid for themselves in a month.

Almost without exception every business can make some improvements. Large-scale works might be eleigible for a grant. Many changes can be made with no or very low investment. Some improvements just need a slight shift in habits. Every time your company looks to make any change see what can be done to make energy efficiency improvements as part of that process. Talk to businesses of a similar size, sector or location to see how they’ve improved their carbon footprint, brought down bills and put in place a spot of future-proofing. And download that PDF.

What are we up to?

We’ve been researching the options for having vinyls cut to cover the Petflap. Some customers don’t want black, so we’re looking at providing white vinyls, and maybe even custom options. Remember we ship worldwide and now have a new improved cart that makes it all much easier.

Thank you for listening to episode 11 of the Energy Efficiency Podcast. Until next time you can find us on both Twitter and Instagram as Ecoflap, and on Twitter we also tweet as The Petflap. In next week’s episode we’ll look at BREEAM, the health benefits of energy efficiency, and mending household items.

Music credit: “Werq” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

Hydropower: The Energy Efficiency Podcast – episode 10



Welcome to Hydropower: The Energy Efficiency Podcast – episode 10, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.

This week: hydropower – is it really as green as it seems? Energy efficiency in tourism – how can we travel without harming the places we want to see? And starting our look at different types of insulation, we ask what is Kingspan?

But before we get on with our advertised features, this week website Solar Power Portal reported that the National Grid is using artificial intelligence (AI) to improve solar forecasting by a third. Poor forecasting can result in power system instability and higher operating costs. In some countries, for instance Australia, power generators are penalised for providing inaccurate forecasts. Improved forecasts help the National Grid and similar organisations worldwide run their systems more efficiently and economically. As renewables form an increasing chunk of our energy mix, this facility becomes ever more important.

The National Grid is working with the Alan Turning Institute on this project. Named after the pioneering mathematician, computer scientist, philosopher and Bletchley Park code-breaker, the Alan Turning Institute conducts research into AI. The project is funded by the Ofgem Network Innovation Allowance.

In this case, AI helps by churning through many more variables than the National Grid has historically been able to do. The results are combined with other machine learning techniques to come up with a more accurate forecast. In Colorado, USA, an AI project focusses on wind power. The system draws information from satellite reports, weather stations and wind farms. Algorithms identify patterns from the data and make predictions based on them. The British project also includes wind data. Today though the AI won’t have to work very hard to forecast that as it’s cloudy and damp, solar is providing just 9% of our power.


The Three Gorges Dam, China

We had already planned to cover hydro power this week before Toddbrook reservoir at Whaley Bridge in Derbyshire began to show signs of strain. There are nearly 3000 dams in England, Wales and Scotland. They’re for drinking water, canal management and so on, but some are part of hydro-electric schemes. Worldwide, dams are commonly part of hydro-electric energy generation. The Three Gorges Dam in China is the largest in the world. While hydroelectric power is viewed as a low carbon means of economic development, building dams is controversial environmentally.

Environmental cost

Fish ladder at Pitlochry

As we looked at last week with wind power, there is an environmental cost to building hydroelectric power stations. Concrete is a big environmental bad boy. The only mitigating factor is that across the lifetime of a hydro plant the emissions will be offset by emissions-free electricity. At the moment the five largest power stations in the world are hydroelectric power station with dams.

Apart from the emissions associated with building dams, they interrupt the local ecology and emit greenhouse gases. Fish migration can be badly affected but this can be improved by fitting fish ladders. Research in America has led to the development of turbines that fill or injure far fewer fish. Dams affect local agriculture by diverting and storing water and affecting water chemistry and silt formation. A recent report described the human costs of large dams as “routinely underestimated”. Communities can be displaced when fishing and agriculture are affected, and land is taken for building dams and reservoirs.

Smaller plants

Water wheel

Recognising these negatives, the EU encourages the use of smaller hydro plants that don’t use dams and is funding several projects of this type.

Domestically, you can put a turbine in a river, or resurrect a water wheel to generate power. Water wheels are quite cheap but don’t produce a great deal of power. Putting a turbine in a river will generate more.

Hydropower has been with us for millennia. It’s been used to power all sort of mills, hammers, cranes, lifts and so on. Now we use it to generate electricity. In 1878 hydro-electric power was first used to power a house (the magnificent Cragside in Northumberland), and in 1879 the first commercial hydroelectric power plant was built at Niagara Falls.

How does it work?

Hydropower is the process of creating energy using the power of flowing and falling water to spin turbines. Hydro provides 18% of the UK’s renewables, in fourth place after wind, biomass and solar, and overall just under 2% of our energy output. Worldwide though hydro is the main source of renewable energy. 71% of renewable energy generated globally comes from hydro. That makes up 17% of the world’s total electricity. Hydro is popular in Russia, Brazil, China, the USA and Canada.

Pumped storage

Hydropower can be generated in a number of ways. It uses water from many sources including the sea. Pumped-storage hydropower can be switched on quickly when power needs escalate. Water flows from one reservoir down to a lower one, using gravity. It passes through turbines as it goes, powering the generator. Later, when demand is lower again, the water is pumped back up to the top reservoir.

This uses so much power it can cancel out the energy created, so its main benefit is the surge of power it provides at short notice. For this reason these hydropower plants are usually dormant and activated only when needed. The biggest hydro plant in the UK is a pumped-storage system. It’s in Wales and at maximum can supply 2.5 million homes. That’s more households than are in the whole of Wales. In Scotland the Cruachan Power Station has been supplying back-up power since 1965. Scotland and Wales both produce far more hydropower than England.

Run-of-the-river hydropower is created as rivers naturally run through turbines. This type of power is variable, difficult to control and creates low quantities of power. It’s low cost, and doesn’t give off greenhouse gases. Reservoirs can give off greenhouse gases as vegetable matter decomposes in the water. This is worse in warmer countries. Washing State University in the USA carried out research showing that 1.3% of man made greenhouse emissions worldwide came from reservoirs.

Tidal hydropower

Tidal hydropower is a modern innovation. As the tide goes out and comes back in water passes through turbines. This powers a generator. Tides are predictable and frequent so this type of hydropower is reliable and sustainable. It is though not as proven as other methods so there aren’t many projects on the go. This is a chicken and egg situation but there are lots of planned projects including the Swansea Bay Tidal Lagoon.

Originally Tidal Power plc, the firm behind the project, thought that UK government subsidies would be essential, and they were turned down for that last year. The subsidies would have come from household energy bills. The government felt that the whole project was just costing too much money, certainly compared to offshore wind and nuclear.

Then Business Secretary Greg Clark quoted £700 per consumer by 2050. Now however Tidal Power plc believes it can take things forward without subsidy. This is extremely unusual for new power plants in the UK. Despite Greg Clark’s attitude, according to Wikipedia

“The UK Government’s National Renewable Energy Action Plan of July 2010 envisaged between 40 and 50 MW of new hydropower schemes being installed annually up to 2020. “.

Tidal Power has signed PPA – power purchase agreements – with several big companies including Cardiff airport. Signing enough of these would ensure construction could begin next year. They also plan to add floating solar panels to boost the amount of energy generated.

How does a tidal lagoon work?

A tidal lagoon is a U-shaped construction built out from the coast. It has a bank of turbines in it. As water flows in and out through the turbines power is generated. If you’d like some facts and figures, shutting the turbine gates for three hours leads to a build up of 4m of water. That can then shoot through 60m long tubes and rotate turbines 7.2m in diameter. There will be 16 turbines. Tidal Power plc states on its website that electricity will be generated for 155,000 homes and that the project will keep going for 120 years!

Energy Efficiency in Tourism

For quite some while now it’s been clear that vast numbers of tourists can easily damage a destination. In some places tourists are literally destroying the place they’ve come to see. This is a complex and multi-faceted issue, so how do we travel without making things worse?

Usually a trip abroad starts with deciding where you want to go, but let’s stop there. Many popular destinations are now having to restrict numbers of visitors and what those visitors can do. Increased affordability of travel means that some places are now seeing previously unimaginable volumes of tourists. Superficially this is great for the economy, but it’s a short-term benefit if a city becomes a hollow tourist trap routinely hosting more people than it can feasibly accommodate.

Venice in peril

Venice is a beautiful destination and popular destination, but it is in trouble due to the 30 million tourists who arrive each year. Walkways and travel networks are congested, the massive cruise ships disgorging at its wharves disfigure it, and it takes hours to get into a church or gallery. The locals are leaving as tourists take over. Sanitation and recycling facilities can’t keep up. It’s in danger of losing its UNESCO World Heritage Site status. But you know all this. What can be done? Simply, visitor numbers need to drop to a manageable level in all Italian cities.

Tourist tax

A tourist tax of up to E10 is being imposed in Venice to fund restoration work on the city, so some people need to visit, but it needs a breather. Work is underway to install underwater barriers to moderate how much water enters the lagoon. The Italian government voted to ban the larger cruise ships – over 100,000 tonnes – from entering the Grand Canal, but this isn’t yet happening.

The thing that many of these 30 million people are missing is that there many other beautiful, historic and fascinating towns and cities to visit that would welcome the tourist dollar and aren’t (yet) mobbed. Instead of Paris, Rome or New York, look further afield. I’ve been lucky enough to travel abroad to stay with family in several different countries, and the view you get off the beaten track is fascinating.



Ideally, a holiday location will be reachable by train rather than plane. Flying is a massive carbon contributor per mile. If you’re heading to a rural area sustainable travel can be tricky. If that’s an area that you prioritise, look at travelling to a less obvious town or city in your chosen country. It’s likely still to have decent public transport links, and you could consider taking a day trip or overnight stay to the main city you had in mind. In other words, if you want to visit the Rijksmuseum you don’t have to stay in Amsterdam. Hilversum, Delft or Alkmaar all have a great deal to offer.

While you’re away do all the things you normally would, such as carrying a drinks bottle for refilling during the day. Good habits travel with you.


But not all sustainable tourism responsibility should fall on the traveller. Many countries derive a significant chunk of GDP from tourism and it supports millions of jobs. If we all stopped travelling tomorrow it would cause abject misery. Ethical tourism is distinct from sustainable tourism in as much as it looks at the social effects on locations as part of the bigger picture, as well as environmental considerations. Ethical tourism will look at whether locals are suffering because in areas of short supply the best is kept for tourists. These and more are very real considerations, but here we’re discussing the carbon footprint and wider environmental fallout.

Many holiday destinations and small accommodation centres promote themselves as environmentally-friendly. What should this mean? To some extent this depends where you’re going and the type of holiday you’re having. Choosing an environmentally responsible destination supports the sector by showing demand. Aside from the ethical considerations look at recycling, energy use (that’s going to be for heating if you’re visiting Santa in Lapland, and air conditioning if it’s Bangkok in the summer), water use, food waste and so on. Food waste is a big consideration for ‘all in’ holidays where big trays of food are presented buffet-style.

Support for businesses

Saint Kitts

The Caribbean Hotel Energy Efficiency Action Programme (CHENACT) has been created to encourage energy efficiency in the region. The programme won the award for Best Energy Efficiency Project 2018 at the Caribbean Renewable Energy Forum. CHENACT focusses particularly on hotels under 400 rooms. It emphasises energy efficiency, renewable energy and micro-generation. So far more than 150 hotels have gone through detailed audits and received training. On average they make savings of 50% in both energy and water consumption.

In Europe the HOTREC charter has been signed by a number of industry groups including the European Tourism Association and Companies for Energy Efficiency in Buildings. HOTREC is a basis for sharing information, promoting best practice and promoting energy efficiency through partnerships. The aim is to improve energy efficiency and reduce greenhouse gas emissions in hospitality and tourism. The charter will reach nearly 2 million hospitality businesses in Europe. It recognises, like the Caribbean initiative, that it’s harder for small businesses to meet the challenge.


I have on my desk something I can more or less guarantee no other listener will have: our local parish magazine. I know the village show this weekend is very exciting, but that’s not the most interesting feature in the magazine. We live near a Kingspan plant. Kingspan sponsors various local facilities and wants to be a good neighbour. It has already comitted to be net zero by 2020, and has taken out an ad in the parish mag to share the news that along with three other plants, it’s operating at 102% net zero. It’s meeting all its energy needs for the four sites through renewable sources.


Ironically, one measure it took to achieve this was improving insulation in its buildings. Kingspan, or to give it its full moniker Kingspan Insulated Panels, if you haven’t come across it before, manufactures insulation. It has fingers in a number of pies, but insulation is probably what it’s best known for. It describes itself on its website as

“the global leader in the design, development and manufacture of products and solutions for advanced building envelopes. Energy-efficiency is in our DNA, from manufacturing the most thermally-efficient and air-tight insulated panel building envelopes with integrated solar PV and smart lighting systems, to providing services that support sustainable building techniques.”

Like many people, I have Kingspan plasterboard insulation panels in my house. They’re fitted to an external north-facing wall, and that room never feels particularly cold. Kingspan insulation has a good reputation for being very insulating. However there are some question marks. It’s easy to find controversial videos online showing Kingspan to be easily flammable and to emit very unpleasant fumes. It’s unclear whether these relate to any real-life scenario that might arise. Kingspan provides detailed information about how its products fare in fire safety tests so you can make up your own mind.


What Kingspan isn’t is a particularly environmentally friendly product. Essentially it’s a foam product, made of materials including polyurethane. Isocyanates are used in the production of polyurethane. The Bhopal disaster in 1984, a gas leak at at a pesticide plant in India, was caused by the release of an isocyanate. Isocyanate is considered a potential human carcinogen and the legal limit for exposure is set low. Non-isocyanate polyurethanes have been developed, to address these concerns.

From a construction point of view, Kingspan is lightweight and easy to work with. It can be cut, drilled and nailed. There’s a wide range of specialist varieties available, including sauna insulation board and pitched roof insulation. All products come with comprehensive information including thermal performance, and a Green Guide Rating.

What are we up to? As it’s the school holidays we’ve downed tools once or twice lately but we still have Petflap stock available and are answering all customer enquiries. Did you know we have a cut-out-and-keep life size pet access flap available to download from our site? If you have any concerns that your cat might not fit through you can now test it out. Really quite large cats go to and fro through the Petflap no bother.

Thank you for listening to episode 10 of the Energy Efficiency Podcast. Until next time you can find us on both Twitter and Instagram as Ecoflap, and on Twitter we also tweet as The Petflap. In next week’s episode we’ll look at grants for energy efficiency works, sheep’s wool insulation, and energy efficiency in business.

Music credit: “Werq” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

Wind Power: The Energy Efficiency Podcast – episode 9

Wind Power

wind power
Wind farm

Welcome to Wind Power: The Energy Efficiency Podcast – episode 9, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.

But before we get on with our advertised features, this week the Guardian reported that architects and engineers are calling for a ban on glass buildings. Glass buildings become extremely hot in the sun and use lots of energy to cool down. This carbon-emitting energy requirement makes no sense in a climate emergency.

In theory using glass to let in light and create heat is a good thing, but when it’s managed properly. Solar gain is an important element of passivhaus design, where it is understood and carefully managed to prevent occupants overheating. Many corporate and commercial glass buildings are designed just for looks. In these heat can build up to unbearable levels without heavy duty air conditioning. As we looked at in our feature on passive cooling, energy used to cool buildings has doubled in the last few years. Buildings can still benefit from solar gain in winter with smaller windows. Natural ventilation can make a huge difference but this can be the short straw in a polluted and noisy area.

Some steps are being taken. Mayor of New York Bill de Blasio has banned excessive use of glass and steel. This is a bit of a climbdown from the ban he spoke of originally. Sadiq Khan, mayor of London, has ruled out a ban. This is surprising given how forward-looking the London Plans have been on the benefits of green technologies (we looked at this last week in the green roofs feature). The new London Plan, coming into force next spring, requires an assessment to be made of a building’s lifetime energy use. It’s hard to see how a standard glass building would come out well of this assessment.

In the Guardian article Martin Fahey, head of sustainability at Mitsubishi Electric, referred to the importance of keeping air conditioning equipment in good working order. Maintenance of equipment has come up repeatedly in keeping energy efficiency at optimum. Fahey hopes that commercial customers will want to do the right thing if only for the sake of their image.

The Edge, Amsterdam

Some hi-tech glass can become opaque in hot weather. Others can generate electricity, such Deloitte’s Edge building in Amsterdam’s Zuidas business district. It uses intelligent design to cut its energy requirement by 70% on a similar building. On three sides it has smaller, opening windows, and one face is glass. It’s been awarded the world’s highest BREEAM rating (Building Research Establishment Environmental Assessment Method) This isn’t a magic bullet however as the specialist glass is nigh on impossible to recycle.


wind powerWIND POWER

It’s a rainy day today and demand on the grid is higher than I’ve seen it for a while. We’re using no coal or oil. Natural gas is providing almost half our power, via CCGT. Renewables are providing about 27% of our power and wind is contributing 10% of that. What is wind power?

As the NES website says, wind power ain’t new. It’s been pushing boats along and powering windmills for thousands of years. It’s magic, actually. Well, no it’s not but as the wind turns the blades which turn a shaft, a generator converts that kinetic energy into electrical energy. That’s where the magic happens. The electricity is then converted into the right voltage for the local network and exported to the grid. A gentle breeze is enough to turn the blades, but faster winds generate more electricity. If it gets too windy wind turbines will shut down to avoid suffering damage. From an individual wind turbine on a house to giant wind farms out at sea, the mechanics are the same. One standard onshore wind turbine can provide enough electricity to power 1,500 homes a year.

Obviously wind turbines are carefully located to pick up maximum and consistent wind. Hilltop and coastal spots are good, which is why Cornwall and Scotland are such popular locations. British turbines produce wind up to 80% of the time at up to 50% efficiency. Because they produce most electricity in the windiest weather, they’re producing well when power is most needed. This makes for a reliable source of renewable power.

Capacity is growing in the UK. Last year wind generated 15% of the UK’s power. There are nearly 10,000 wind turbines here which together produce enough power for nearly 15 million homes. There are around 27 million households in the UK.

Building wind farms

We’ve all heard the arguments that the construction of wind farms is very damaging for the local environment. Does that view hold up? We’re discounting here the visual impact as minding about that is a luxury we can’t afford at the moment. Habitat loss however is a real consideration. Bat and bird deaths increase around wind turbines, with bats suffering worse than birds. this can be mitigated by careful siting of the turbines. Data is still being gathered and the overall impact on wildlife is as yet unclear. It’s worth mentioning that climate change is worse for wildlife.

Noise can be an issue for those living within about a mile of a wind turbine. It can affect birds and animals nesting near turbines.

Wind is a less environmentally damaging way of generating power than acquiring fossil fuels. According to wikipedia wind turbines have the lowest global warming potential per unit of electricity generated compared to other renewable power sources. Purely in the production of energy then (as opposed to making the machinery), wind power uses no water and has negligible emissions. Building the components does create emissions, in some cases higher than that of building a gas-powered station, due to the concrete required for the foundations. In less windy areas more back-up is required, needing either battery storage systems or fossil fuel plants. The bringing on- and off-stream of these other power sources can be power hungry. Magnets used in some wind turbines us neodymium. Extracting this rare earth element is polluting and research is underway to reduce or eliminate the need for neodymium. Turbine manufacturer Enercon doesn’t use permanent magnets for its direct drive turbines to avoid the need for rare-earth mining.

Measuring the impact

Measuring the impact of wind farms can be approached from many angles. The ground clearing and disturbance needed for a wind farm is less than for coal mines and coal-fired plants. In the UK many ideal wind farm sites are  covered in blanket bog. Construction will disturb this crucial habitat. The action of the wind turbines can cause localised drying of the peat. When dry, peat releases its carbon. Livestock quite like wind turbines. They graze right up to the foundations, stand in the shade and use them as scratching posts! An article in SciTech Daily says this:

“The direct climate impacts of wind power are instant, while the benefits of reduced emissions accumulate slowly. If your perspective is the next 10 years, wind power actually has — in some respects — more climate impact than coal or gas. If your perspective is the next thousand years, then wind power has enormously less climatic impact than coal or gas.”


What about offshore wind turbines? 15 new offshore wind farms were completed in 2018, with the UK and Germany in the lead, particularly the UK. Yesterday Prince Charles opened Scotland’s largest offshore wind farm, Beatrice. Located off Wick, the farm can power 450,000 homes. For comparison, the world’s largest offshore wind farm, off the cost of Cumbria, can power 600,000 homes.

Of course there are concerns about the impact on marine life and commercial fisheries. Sound-sensitive marine mammals are of particular concern. Offshore wind farms need bigger blades and turbines to cope with strong sea winds (which create more electricity), and they must be robust. It’s very expensive to fix turbines, wherever they are. Better undersea transmission routes mean offshore wind farms can be sited away from objectors and obstacles. Whales can migrate undisturbed, valuable beachfront properties don’t need to look at them, and shipping can move unimpeded. All of this has been a big deal in the USA which is only now moving forward with offshore wind. Wired has an interesting article on the subject, link in the show notes.

Domestic wind power

wind power
Roof-mounted wind turbine

Domestic wind turbines can be fitted to individual homes. It’s extremely expensive. The Energy Saving Trust quotes between £10 and £30,000. The turbine attaches to a pole or to the house. House-mounted are cheaper, but less efficient. In high winds they can vibrate and damage the structure of the building. As with solar panels, the inverter might need replacing at some point, at a current cost of £1-2000. The installation should last 20 years. Off-grid systems will need batteries replaced every 6-10 years. As we looked at last week for off-grid solar consumers, batteries are a very expensive option.

A typical house usually requires a home wind turbine with a 5 kW generating capacity to meet all its energy requirements. This is unusually large for a domestic environment. To be worth having though a wind turbine does need to be a minimum sensible size and in a good windy space. Usually that will be tall and away from trees and buildings. Accommodating that is going to be tricky in an urban area. Compared to installing solar panels, domestic wind turbines are a less obviously attractive option. Most people wanting to access wind power will be better off choosing a well-researched green tariff.

Energy efficiency when you have a baby

A pregnancy is a marketer’s dream. Pregnant women are exposed to a volley of adverts all designed to make them believe they’ll be a better mum with x, y or z product. Fortunately most women are savvy enough to realise that maternity clothes, baby clothes, cots and prams are fine for seeing you through more than one baby. If you want to keep your carbon footprint to a minimum, where do you start? I should say I’m looking at this from the perspective of a parent in the developed world.

Home improvement

If your baby’s going to arrive in the colder months, you’ll want to make sure they’re warm enough. There are many ways to achieve this, but start with the room where the baby will sleep. Make sure you’ve paid attention to draughtproofing. Windows and floorboards can be trouble spots in bedrooms. If you’re able to fit big measures such as loft or wall insulation now is a good time. When a baby arrives you may well be at home far more than before, and if that’s in the winter (I speak as the mum of a December baby) you’ll be very aware of how cosy your home is or not.

Look at your lighting. If you’re suddenly at home for hours in the daytime when you used to be at work, your heating and lighting bills will go up in the winter. You’ll go through more hot water. You’re likely to be more tired than you could ever imagine, and so you feel the cold more. Make your home as snug and as economical to heat as possible before looking to smaller considerations.


When baby no 1 is on the way you’ll need everything, but what is everything? If you aren’t a kit monster or an ascetic, you’ll be looking for standard kit without going overboard. The baby needs to sleep, eat, eliminate, and stay a comfortable temperature. Sometimes my daughter would sleep wrapped in a blanket popped into a washing basket. She was easy to carry without disturbing and she couldn’t roll off anywhere, but I’m not recommending it. What I’m saying is that you don’t need a special cot at first. A moses basket can do to begin with. These can be found second hand, but a new mattress is recommended for any second hand sleeping furniture.

Check that any second-hand items meet current safety standards (no lead paint, for example). Most families will want a cot at some point, and these are easy to find second hand. Again, buy a new mattress and look at the chew bar, which might need replacing. Without going through an entire kit list, most items you need can be second hand without any reduction in quality or functionality. You might even be able to get the pushchair or designer maternity wear of your dreams if you’re prepared to buy it second hand.

Car seat

One item not recommended to buy second hand is a car seat. If you’re buying from someone you don’t know you can’t really know the history of the car seat. It’s possible it’s been in an accident and could be damaged in ways you can’t necessarily see by looking. This could make it less effective at protecting your baby in an accident, and that’s not a risk worth taking. Using your own car seat through more than one child is up to you.


Many parents find that the washing machine is on all the time with small children. This is the case whether you use cloth nappies or not. Soaking mucky clothes before washing means you can wash on a shorter cycle at a cooler temperature.

If you can dry clothes outside so much the better, but in October in the UK that’s asking a lot. If you have the space a rotary washing line with a rain cover will allow you to dry clothes outside whatever the weather, or at least reduce tumble drying time. The covers aren’t cheap, but are less expensive and co2 emitting than buying and running a tumble dryer. Otherwise a covered outside area or garage with a front and back door open are good spots for clothes horses or lines. Air movement is as effective as heat at drying clothes.


One of the big decisions parents face is whether to use cloth nappies. I think it’s fair to say that the jury’s out as to whether it’s worse to use the electricity and water to wash cloth nappies or to manufacture disposables. If your metric is the content of the nappy, so to speak, then cloth wins every time over the gels in disposables. Cloth can be used almost infinite times making them a great second hand buy, fantastic to use for several children, and can then be sold on. Cloth nappies are a science and an art all of their own, so I won’t attempt here to make any recommendations.

Nurseries can be iffy about cloth nappies if they don’t see them often. I found a quick demo sorted out any problems, and that was 10 years ago. Things will have improved since then. Using cloth doesn’t have to mean never using disposables, but it does mean fewer in landfill taking forever to decompose, which has to be a good thing. Nappy washing services exist in many areas, as do nappy libraries. In many areas of the UK council grants are available towards buying a set of cloth nappies, so look around if you are considering them.


Eventually your baby will want real food. To keep your carbon footprint down, provide your baby with home made food. Pouches and jars are easy and quick, but more energy-intensive to produce, package and transport. The same goes for formula milk and all its paraphernalia. If it’s open to you, breastfeeding means less CO2.


Babies don’t actually care what they wear. Until children are surprisingly old they can go through at least one if not several changes of clothes a day. Spitting up, eating, painting, mud, accidents, falling over, finding your nail varnish and so on, they get in a real mess. Save yourself a bomb and the planet some CO2 by buying a job lot of baby clothes. Accept cast-offs from family and friends. You will never look back and wish you’d spent more on baby clothes.

Many people sell their children’s clothes in age-range batches on eBay and Facebook, and it’s a great way to buy. I start off buying my daughter, baby no 1, new clothes and kit, but swiftly came round to second hand. By the time my son was on his way and I’d acquired two stepchildren, second hand was the way. I was lucky that my sensible friends had finished having babies and gave me almost everything I needed (and had got rid of a few years before).


Toys are an area where it’s easy to spend a fortune for little gain. Children are very happy playing with simple toys, and you can add things as they get older. Second hand toys are great. Many toys can be put through the washing machine, washed with soapy water or even sterilised in the microwave. You’ll find children with shedloads of toys often ignore 3/4 of them and play with the same two or three favourite things for a while, then move on to the next favourite items.

Keep toys cycled by donating to charity any you know your children have finished with. Toy libraries exist, and of course there’s the book library. These can be great places to spend time with babies and young children.

But having children doesn’t have to be a hair shirt exercise in frugality. Yes insulating your home and buying used items will save you money and the planet further emissions, but you can view this as saving you money and carbon footprint for the things you know you will really benefit from. You can economise after spending money improving your home. Save money towards your first night out without children, or even the dizzy heights of a weekend away. You might need a bigger car. You might even need a bigger home. Save money and carbon where you can, and spend it where you need to, like in the wine aisle.

Transition Towns

Wikipedia defines transition towns as ” grassroot community projects that aim to increase self-sufficiency to reduce the potential effects of peak oil, climate destruction, and economic instability.” It seems to come down to local community-led environmental change, within a group mindset. The core principle is reducing reliance on fossil fuels and use resources wisely. By networking, transition towns benefit from freely shared experience to create change quickly and inclusively. The economic aspect of this is known as Reconomy. The Transition Network defines a transition-orientated business as:

“They provide essential goods and services for the community in which they make their home, create meaningful, satisfying jobs and buy from other local independent businesses. A Transition Enterprise is a financially viable trading entity that fulfils a real community need, delivers social benefits and has beneficial, or at least neutral, environmental impacts.”

The network would like to see this type of business providing services across a range of sectors including food, transport, energy and housing.

Global reach

Transition is now a worldwide movement. In the Netherlands Bakery De Ondergrondse (the Underground) produces bread to order. It serves co-operative shareholders and occasional external customers. Flour comes from a local windmill. The bakery teaches breadmaking and helps other co-operative bakeries start up.

In Croatia a bike repair project provides the tools, space and expert volunteer help for mending bicycles. As people acquire skills they in turn volunteer their help. This is a great example of the positive and contributing mindset of transition. Canapuglia in Puglia, Italy, has used hemp to great effect. Growing it repairs depleted soils. The end product is used in building, food, medicine, textiles and paper. This small organisation has spread great enthusiasm through the local area at every level. In Belgium a small company provides logistics service by bike. There’s a similar service in Hereford, Pedicargo.

Moving towards Transition

In Meerlanden in the Netherlands a traditional waste disposal company is progressing towards becoming a Transition-minded outfit. Now the compostable wasste they collect is processed into gas, co2, heat, water and compost. They fuel their fleet on the gas and will be making this fuel more widely available. The heat feeds local greenhouses and the water is used for street cleaning. In the springtime, all participants get free compost for the garden. This example shows that traditional businesses can add value to their community without suffering any penalty.



In the UK, transition towns include Lewes in Sussex and Totnes in Devon. Totnes was the first official transition town in the UK. Many towns run activities that fit within the transition definition without formally designating themselves transition towns. Lewes is running a repair cafe, and this happens in Leominster in Herefordshire too, but Leominster doesn’t describe itself as a transition town.

Lewes is looking to work with OVESCO, which describes itself as “a not-for-profit community benefit society”, to fit solar panels on schools in the county. Investors buy shares in the installations. Lewes is making a plastic-free pledge (another measure adopted by many towns not describing themselves as Transition towns) and developing its Neighbourhood Plan on an “ecosystem approach”. An ecosystem approach considers the environment when making planning decisions. It identifies the benefits to residents of the natural world and features around them. Aims include reducing flood risk, energy use and water use, and maximising residents’ access to nature.

If you are in Devon or can get there, Totnes is running Transition Walks. There are four more dates this year, in August, September and October. If you’d like to find out more about what transition is, and how Totnes has benefited and contributed, these walks sound like a great place to start.

And what are we up to? Well actually we’re working on our own wind turbine design. This is under wraps for the time being. We had a good photoshoot with cats on Friday. Honey and Blackcat were purrrfect models and some of the shots are up on our website and social media.

Thank you for listening to episode 9 of the Energy Efficiency Podcast, available through Apple Podcasts. Video version os some episodes are available on YouTube – look for the Ecoflap channel where we also have product videos. Until next time you can find us on both Twitter and Instagram as Ecoflap, and on Twitter we also tweet under The Petflap. In next week’s episode we’ll look at hydropower, energy efficiency in tourism and start our look at different insulation materials.

Music credit: “Werq” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

Solar power: The Energy Efficiency Podcast – episode 8

Solar Power

solar power
A solar array in the USA

Welcome to Solar Power: The Energy Efficiency Podcast – episode 8, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.

Before we get on with our advertised features, on Monday morning the Guardian reported on a scheme to generate domestic fuel from dirty plastic waste.

Dirty recycling

Items for recycling should be clean and contain nothing non-recyclable. This is why mixed materials are such an issue. Recyclable materials are wasted and go to landfill if they’re mixed up with non-recyclable materials in the same item. If recycling is dirty it can’t be used.

The worst culprit is food. That’s why silver foil is not usually recyclable. It’s infinitely reusable if it doesn’t get dirty as such, but the foil with bacon fat all over it has to go in the bin. If a householder knows this then contaminated waste won’t enter the recycling foodchain, but mistakes happen all the time. That’s distinct from aspirational recycling, when items go in the green bin in the hopes they can be recycled. Or perhaps the belief that they should. Even paper and glass can be contaminants if they go in the wrong bins. To quote Rubicon Global,

“Contaminants turn your recycling into nothing more than trash.”

This is an entire subject with global repurcussions and one we’ll return to at a later date.


Help may now be at hand. Work at the University at Chester has been looking at how to use this dirty recycling to create fuel. Researchers have found a way to produce hydrogen. Hydrogen can fuel homes and cars without emitting greenhouse gases. Waste is burnt at 1000 degrees in a glass kiln. The waste instantly breaks down to release gases including hydrogen.

Two waste energy business have come together to develop this research commercially. Later this year production will begin at a plant at Ellesmere Port in Cheshire. Owner of the plant Peel Environmental reckons that a walloping 25 million tons of contaminated recycling will be kept out of landfill and the seas.

Why is hydrogen such a big deal? Hydrogen can take over tasks currently met by traditional gas. Hydrogen can be used for cooking, heating homes and hot water, and fuelling vehicles. It could play a huge part in the UK meeting its climate targets.

There is a downside however. The production of hydrogen emits powerful greenhouse gases including methane. Methane is a disaster, but the plant plans to trap it and use it to generate electricity. The Guardian article describes this process as no “more polluting than the UK’s existing gas-fired power plants”. That’s not a ringing endorsement, but it goes on to make the point that it means no more gas need be pulled from the ground. It highlights again the need for effective carbon capture technology.

solar power

The technology has been developed in collaboration with Asian companies. Hydrogen fuel is already commonly used in Japan, as we looked at in episode 3. Increased production of hydrogen in Asia would make strides in reducing their dependence on coal burning plants. Ep 3 looked closely at fuel use and generation in Japan.



Solar Energy

solar powerMid-morning on Monday 22nd July, renewables are providing 15% of the UK’s power requirements. Wind is producing about 2/3 of that, solar power most of the rest. It’s a bright sunny day in parts of the UK and it’s windy. We’re using no coal or oil just now. So would fitting PV panels to your home keep you in electricity all year round? Let’s look at the facts.

Photovoltaic cells – PV cells – work by turning sunlight into an electric field. More sunshine means more electricity but PV cells don’t need bright sunlight to generate electricity. They will generate some electricity on a cloudy day. The Energy Saving Trust website says that a typical domestic array could save from 1.3 to 1.6 tonnes of C02 per year. This makes solar panels a better bet in the UK than you might at first assume.

In the UK domestic PV panels are commonly fitted in groups to a roof. The alternative is a roof made up of solar roof tiles. Solar roof tiles are used instead of regular tiles. This will be about twice the price of fitting solar panels. Generally they aren’t as effective and according to the EST are used where there are aesthetic arguments against solar panels.


A house must be assessed for the suitability of its location, and the strength and pitch of of its roof. Planning permission might be needed. This usually depends on the size of the proposed installation. A listed building would also likely need listed building consent, similarly a building within a World Heritage Site. Your buildings insurance could be affected, so there are plenty of points to check on if you’re considering solar power. But a roof isn’t the only possible location for solar panels. A solar array can be fitted on the ground, but they are far more susceptible to damage and dirt. Dirty PV cells are less effective simply because less light reaches them.

Although we are looking here mainly at ways of heating your home, solar power offers a standalone water-heating option. Solar thermal panels use the sun’s warmth to directly heat water. This is transferred to your hot water tank. Again they don’t need to be on the roof but they do need good strong direct sunlight. You will need a compatible boiler, but most are compatible. The cost of fitting solar thermal panels is only a little lower than fitting solar panels. In winter the system will likely produce very little if any of your hot water requirements.

Solar panels are a sensible heating solution for off-grid homes. Taking electricity to remote homes is prohibitively expensive, so on-site generation is popular in far-flung locations. With effective storage batteries, combined sources of power and careful use, an off-grid electricity supply can be maintained. However battery systems are very expensive, with the Guardian quoting £4000.

Surplus power

As with other renewables, a householder can sell surplus power back to the grid. Schemes supporting this system have been all over the place in the last couple of years. If you’re planning to fit solar with this in mind, do your homework.

From 2020 the UK government will require most electricity suppliers to offer you something for your power. This is known as the Smart Export Guarantee, SEG. The government blows hot and cold on this. The Feed-In Tariff (FIT), which gave householders producing solar power a payment based on how much they produced, was scrapped in April this year. A 94% drop in installations swiftly followed, according to the Guardian. This follows getting on for a million households having installed solar panels since the launch of the scheme in 2010. Subsidies were slashed in 2016 but rather than expecting its death, supporters had hoped for a replacement.

Set against what can be the high cost of installation, this puts the benefits of lower bills out of reach of most householders. It also takes chunks out of the CCC’s plans to achieve net zero. A solar array might be eligible for the Renewable Heat Incentive, which we looked at last week in relation to ground source heat pumps. VAT on solar panels leaps from 5% to 20% this October.


Fitting a standard domestic array will cost £6-7000. The price has come down over the last few years. It should last 25 years. In that time the inverter may well need to be replaced. Currently they cost about £800. The inverter changes direct current (DC) into alternating current (AC). We use AC in all appliances in the UK so the inverter is crucial to being able to use the electricity PV panels generate. Inverters are the part most likely to go wrong with a solar installation. When it fails no energy can be produced so the householder immediately loses the benefit of the installation. It can be very expensive to fix inverter problems.

The EST has a graph on its site showing the payback times for different domestic set-ups. It looks at different areas of the country and compares finances with and without the new SEG.

If you can afford to install solar, how much power will it generate?

solar power
The Falkirk Wheel

Solar power is measured in kWp – kilowattpeak. This is the maximum power that can be generated by any given installation in the best conditions. It varies from place to place. In southern England a 4kWp installation will generate about 4200 kWh a year. That would turn the London Eye 56 times. In Scotland, traditionally cloudier and wetter (though far from always the case in my experience) the same size array generates about 3,400 kWh. That would turn the Falkirk wheel 2,200. The Falkirk Wheel is a rotating boat lift.

PV panels don’t need much maintenance. They need to stay fairly clean. Make sure they aren’t overshadowed by trees. Birds tend to nest under them. Panels set at 15 degrees or more will be washed clean of debris by rain. The right inclination is important for maximum power generation.


Working solar power into a new build provides a number of benefits. When mooted at design stage, the orientation of a roof can be worked in appropriately. Setting the panels in as part of the roof replaces the need for roof covering in that spot. Unusual or awkwardly shaped roofs can be accommodated. Costs are combined and the job done in one fell swoop.

Businesses could be making even more hay while the sun shines. Estimates vary, but fitting PV panels to commercial buildings in the often cloudy and wet UK alone would produce at least 60% of the energy used by business. The majority of businesses are active only in the daytime, when they can get the most benefit from PV panels. Schools, leisure centres and other large buildings are ideal locations for solar panels. This came up last week when we looked at new build sports stadia.

Without an expensive battery system an average house is unlikely to power itself completely by solar energy. The end of the FIT, increasing VAT and delayed introduction of the SEG all make fitting solar a less attractive proposition financially. The rewards will take many years to materialise and most householders will need access to an alternative form of energy as well as solar. If however you want a source of clean and endlessly renewable energy, you have suitable property and can meet the costs, then solar deserves consideration. It is risk-free and low-maintenance. Looking globally, it’s a good option for the billion or so people who live with no access to electricity. The costs shrink to nothing in comparison with the benefit this could bring to healthcare, quality of life and wider opportunities.

Energy efficiency in medicine

Princess Alexandra Hospital in Brisbane

Hospitals are on the go 24 hours a day. They use up to five times as much power as a smart hotel. In the USA hospitals account for 10% of all greenhouse emissions and 40% of that is from heating.

Some medical centres have seen the light. In Wisconsin Gundersen Health System has switched to renewable power. Using wind, biomass, methane gas and manure, it’s reduced its emssions by 95%. Boston Medical Center took a canny look at how it used space. It was able to downsize while increasing patient capacity. It’s installed a cogeneration plant that traps and reuses heat, albeit gas fired, that supplies 40% of its power and provides back-up in a power cut. Theda Clark Medical Center in Wisconsin is saving nearly $1m a year through retrofit measures. It’s installed low-energy lighting, insulated pipes, turned heat exchangers off after hours and switched the lights off in vending machines.

Common sense

As with leisure centres that we looked at last week, medical centres are large buildings with very mixed footfall. The common sense measures used at leisure centres apply to hospitals. Good maintenance, upgrading old kit with energy efficient alternatives, reducing services to little-used parts of the building. This isn’t easy though. Hospitals are usually under such pressure that allocating time to give engineers access to equipment for maintenance or upgrade is difficult.

The Boston example started with an analysis of how the space was used, prior to a redesign. Bob Biggio, hired to oversee the redesign, realised the centre was far bigger than it needed to be. He says “A square foot you never have to build is most efficient of all.” The new smaller premises obviated the need for ambulance transport between departments. It cut power requirements by nearly half!

Biggio sold his plans on the basis of reduced costs and improved health outcomes; the board wasn’t ready to hear about the environmental benefits. As with many sectors, the financial investment has to be weighed against other calls on money. When starting out on a new building however energy efficiency measures fit in to the vision of the future.

Practice Greenhealth

There are about 5000 hospitals in the USA. 1100 belong to Practice Greenhealth, a nonprofit promoting environmental stewardship. Members make about $1m a year each in savings. A simple measure such as switching off heat and light to an unused operating theatre can save $45000 a year. As energy use in a typical hospital accounts for half of all costs, even modest savings add up.

Smart technologies have a central role to play. The Hospital of the University of Pennsylvania has installed a smart air conditioning master unit known as a chiller. It continually monitors temperatures and turns fan on and off. It maximises cooling with minimum energy, and is reaping cost savings. HUP has recruited an energy manager, who is working with other hospitals in the area to bring down energy use.


The UK government’s recent 10 year plan for the NHS includes energy efficiency measures. These are many and various, everything from selling off land and buildings to building green homes for NHS staff, and include sensible and straightforward measures such as fitting LED lighting. The NHS is a massive consumer of single-use plastics, eg rubber gloves, medicine packing and instrument wrappings. A new NHS wide procurement body will look to acquire sustainable alternatives affordably. 85% of NHS waste goes to landfill, but the 10 year plan was quiet on how to improve that figure. The plan recognises the impact of ambulances and business travel and aims to reduce it.

A whopping 50% of all patients don’t take their medicines correctly. The sheer volume of wasted medicine goes unquantified. 10% of hospital admissions among the over-65s is due to meicine misuse. In response routine prescribing of paracetamol, bandages and other items easily obtainable over the counter will cease.

George Davies Centre

The George Davies Centre at the University of Leicester is the UK’s largest non-domestic passivhaus building. This teaching and medical facility features a living wall. Automatic blinds control solar gain and loss. Scaling up passivhaus to a building of this size and complexity was a huge challenge involving a number of agencies, but it has paid off. The building is five times more efficient than comparable higher education buildings. Older inefficient buildings have closed and the George Davies building is in use for longer hours. Emissions drop and students and visitors spend more time in a more comfortable building.

James Elliment who works for construction partner Willmott Dixon, says,

“Through the three-year soft landings process, we have been able to really understand how to use the building as efficiently as possible. Part of this has involved working very closely with the building’s users to educate them about how the building functions – explaining why the lights automatically dim, how the radiators know when it is too cold and when blinds close themselves, so that the building can perform to its optimum levels. Without this education the performance gap and payback period grow, which is something we have worked to avoid.”

Some of the environmental changes have taken a bit of getting used to. Willmott Dixon has monitored the building’s performance and user experience to achieve the best outcome for everyone. As the building’s use evolves the energy use and requirements must be kept under review. Elliment goes on to say:

“George Davies Centre is one of the lowest energy facilities of its kind in the country and has illustrated beyond doubt that it is possible to meet the challenges of energy reduction while developing an estate and highlighted the importance of working with users throughout the process. This project is exemplar and a benchmark for developments of this scale. It continues to turn heads across both the higher education and construction sectors.”

Living roofs

We touched on living roofs last week as part of the feature on passive cooling. As mentioned just now, a living roof is one aspect of keeping a building insulated. As the planet warms it’s easy to think of this in terms of keeping cool, but for hundreds of years Icelandic houses used turf roofs as insulation from the cold. Turf roofs were still common in Scandinavia 150 years ago. So living roofs aren’t new, but as a modern architectural feature they began to take off in the 1960s.

Many of the benefits of a green roof are pretty much immediately obvious. They’re easy on the eye, breaking up expanses of concrete and tile. They absorb rainwater – 75% of summer rainfall and 40% of winter. That water would otherwise have contributed to run-off and possibly flooding. The plants use the water, and the rest evaporates back out into the atmosphere slowly. This is one way that green roofs break up the heat island effect. They provide habitat for insects and birds and often include beehives. They provide insulation from noise, heat and cold. There has even been a suggestion that they might house herds of cows by the end of this century.

A green roof policy was first included in a London Plan in 2008. In April this year the report Living Roofs and Walls, from policy to practice, revealed that there are now 1.5m square metres of green roof and wall in London. This outstrips cities such as Copenhagen, Toronto and Singapore. Over 40% of the green roof space in the country is in London, arguably where it’s needed most. This has been achieved without subsidies. In those 10 years a body of evidence has grown to support the use of green roofs.


All green roofs are not equal. They often include a mix of vegetation, soil, sand and rock. Green roofs are divided into two categories: intensive and extensive, referring to the level of maintenance required. An intensive green roof usually requires irrigation and several maintenance visits a year. They can be formally laid out and some grow produce. Extensive green roofs consist of slow-growing low-growing drought-tolerant vegetation. They require little maintenace and won’t be irrigated after getting established.

Some roofs are designed to store water, a blue green roof, others solar panels, a biosolar roof. Living walls are also divided into categories depending on their characteristics. These include bioactive facades. In these materials are developed to encourage the growth of organisms such as moss. They are designed for areas where more profuse foliage wouldn’t work.

The report evaluated green roofs and walls against seven criteria:

  • Surface water management
  • Urban cooling
  • Biodiversity
  • Air quality
  • Health and wellbeing
  • Noise reduction
  • Potential for carbon sequestration

In not one category did living roofs and walls not make an improvement.


An article in PlaceNorthWest in September last year argued the case for mandatory green roofs in Manchester. The article makes the point that green roofs shouldn’t be slapped on a building as an afterthought green measure, saying:

“Just as natural landscapes are a composition of varying habitats and ecosystems, the role of green roofs is to contribute to a wider cityscape of green infrastructure, encompassing trees, parks, gardens, bio-swales and green walls.”

The author, Andrew Watson, associate landscape architect at Optimised Environments, emphasises the role green roofs and walls can play as the climate warms. In his experience, plans for a green roof often wall by the wayside as a development continues. He blames this on green roofs not being included in planning frameworks outside London. Amsterdam and New York are among cities that offer subsidies and tax breaks for green roofs. 25 North American cities have passed legislation requiring green roofs or incentivising them.

The City of London might not seem the obvious place for green roof success stories, but there are quite a few. In 2011 the City of London Corporation published a set of case studies including at The Museum of London. The document describes the Museum as “leading by example in innovative and diverse green roof areas”. MoL uses its green roof as a teaching resource. The green roof was put in during essential roof replacement works.

There can be downsides. The green roof on New Court, St Swithin’s Lane, part of the Rothschild’s banking business, attracted seagulls. To try to combat this owl statues were placed on the roof. The report doesn’t comment on their effectiveness. Interestingly, the rundown on New Court mentions that living roofs are now often a requirement of development in the city. In this instance inclusion of a living roof contributed to granting of permission for the construction.


But why restrict yourself to green roofs on buildings? In Singapore 10 buses have been fitted with living roofs. This is a trial to see whether living roofs will keep buses cooler for passengers. In Brussels a mobile living wall removes pollutants from the air. In Kuala Lumpur planting cools bus stops and helps to purify the air.

In Utrecht in the Netherlands bus stop planting has been designed specifically for bees. The planting is looked after by a group of caretakers who travel in an electric van.

Utrecht plans to power a fleet of electric buses by windmill-generated power. A local scheme offers funding to householders to create living roofs. Where there’s a will, things happen.

What are we up to? We’re working on images and web updates at the moment. We’re developing our plans for a microchip reader for the door. We haven’t fitted them to date as we need to be absolutely certain the technology won’t let us down. We still haven’t found reliable enough technology but we’re working on how the parts will work with our manufacturing. We expect the solution we eventually come up with to be a retrofit measure too.

Thank you for listening to episode 8 of the Energy Efficiency Podcast, available through Apple Podcasts. Until next time you can find us on both Twitter and Instagram as Ecoflap, and on Twitter we also tweet under The Petflap. In next week’s episode we’ll look at energy efficiency when you have a baby, wind power, and transition towns.

Music credit: “Werq” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

Ground Source Heat Pumps: The Energy Efficiency Podcast – episode 7

Ground Source Heat Pumps

Ground source heat pumpsWelcome to Ground Source Heat Pumps: The Energy Efficiency Podcast – episode 7, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.

Before we get on with our advertised features, the Guardian reported last week on the progress made towards hitting net zero by various local authorities in England. This is on the back of Labour leader Jeremy Corbyn urging local authorities to take a lead on reducing carbon emissions.

Progress varies wildly across the UK. This will inevitably reflect variations in population density and affluence around the country.

ground source heat pumps
Stroud in Gloucestershire

Since the 1990s Stroud in Gloucestershire has taken this bull by the horns. In 2015 it became the first local authority in Europe to become carbon neutral. As well as undertaking domestic energy efficient retrofits it has fitted solar panels to houses and all municipal buildings. Residents are feeling the difference and spending less on energy bills.


Its grade II listed council building has secondary glazing and internal insulation and sources all heat from renewables. Through collaboration with other local authorities Stroud has boosted recycling rates to 61%.

It has plans for more. It wants to become a carbon neutral area by 2030, 20 years ahead of the government’s target. It will do this by using electric vehicles, making all homes (that’s ALL homes) energy efficient, using low- to no-carbon electricity and heat generation and tree planting. It’s aiming to facilitate cycling, walking and renewable-powered public transport. At this rate Stroud will also become one of the healthiest local authorities in England.

Simon Pickering, a Green party councillor and chair of the council’s environment committee, makes the point:

“It will no longer be business as usual to cut the energy use of all buildings by at least 80%, generate over half the district’s electricity needs from renewable sources and transform how we travel.”

And this is the point, serious policy shift must be implemented by an authority wanting to see results.

However Stroud and other authorities including Nottingham and Oxford are the bold few. Despite widespread announcement of climate crisis among local authorities in the UK many take an illogical approach to carbon reduction. Manchester’s plans for carbon neutrality explicitly exclude emissions from aviation. In Norwich and Hereford there are road-building plans. In Hereford in particular these plans have been heavily criticised for not tackling the real cause of congestion – short city centre journeys that could be replaced by public transport or walking and cycling infrastructure. Going even further, Cumbria County Council has approved opening a new coal mine. This is another example of the postcode lottery at work in the UK.

Ground Source Heat Pumps

Heat pumps are used in about 100,000 homes in the UK. In Sweden, Germany, Switzerland and the USA they’ve been widely used for years.

ground source heat pumps
Underfloor heating going in

Ground source heat pumps (and their near relations air and water source heat pumps) have become the heating method of choice for low-energy builds. This is for two main reasons. Firstly, although they need electricity to run, the heat the pumps draw in is continually and naturally renewed. Secondly, heat pumps work best in a house with levels of insulation and draught-proofing well above average. Due to its lower temperatures a heat pump system tends to work best with under-floor heating and warm air heating systems.

How it works

The temperature a couple of meters below ground stays at around 8-12 degrees all year round. A ground source heat pump extracts this heat through buried loops of pipe about 100m long. The pipe has a mix of water and antifreeze flowing through it. This liquid absorbs heat from the ground and passes it through a heat exchanger to increase its temperature to about 50 degrees. This warmth heats water and heating circuits in the house. The liquid then flows back out into the pipes buried in the ground and the cycle goes on continuously.

If the electricity drawn by a house running a heat source comes from renewables, then this method of heating is very environmentally friendly. According to the Ground Source Heat Pump association website, each unit of electricity used by a heat pump generates 3-4 units of heat. They put this in terms of a well-fitted heat pump achieveing 300-400% efficiency. This beats low-carbon emitting gas heating, with 70% lower CO2 emissions.

Is it right for you?

As with the other methods of heating we’ve looked at, this depends on a few things. The heat supplied tends to be constant but lower than we’re used to with standard gas or oil heating. There are no scalding radiators. This is why a house deriving its heat from a heat pump needs to be insulation and draughtproofed to such a high level. A house not so well insulated and airtight may need additional heating, which will cost money and may produce emissions.


Designing the best set-up for your home requires professional input. There are a number of variations of how a ground source heat pump system can be configured. For instance, if you have the room your external pipework with be buried in a trench up to a couple of metres deep in the garden. This is usually the cheaper option for small smaller systems. If you don’t have the space then a vertical bore can be sunk instead up to about 160m deep. Vertical installations can reach higher ground temperatures. The cost of sinking a borehole can vary hugely depending on where you live. The exact size or depth of trenches need to be assessed by the professional who will take into account local geology (for instance, clay holds more heat than sand). They will consider for instance how big the house is and your heating and hot water requirements. If this isn’t caried out properly or there are any issues with the installation then there may be problems with how well the system performs.

Fitting a ground source heat pump and associated heating is expensive. According to Which it can be less efficient if it’s providing hot water as well as heating. The end of the system fitted in the house can be as big as a filing cabinet, depending on which kit you choose. It’s very long-lasting though and requires inexpensive maintenance. The Energy Saving Trust suggests a yearly check by the householder and a professional check every 3-5 years. There are no safety issues and some elements of the set-up are said to last up to 100 years. Your heating bills will be very low. If it’s fitted as part of a build or refurbishment the disruption will be less and costs can be combined.

Although the government has tinkered with tariffs lately, heat pump heat is eligible for the Domestic Renewable Heat Incentive (RHI). Additionally, ICAX, which describes itself as “a cleantech company”, says,

“The planning authorities like ground source systems as they are safe, silent, invisible heating systems with low environmental impact.”


According to an Energy Saving Trust PDF download on getting the best from your heat pump, the controls can be complex. If you don’t master them the heating may not work to optimum. Its own research suggests that this is something householders do struggle with.

The basic controls comprise an adjustable controller, and a room thermostat. The controller has a number of functions and is typically sited on a wall near to the pump’s installation spot. It manages flow, temperatures of different aspects of the system, allows you to set timings and displays error messages. The thermostat monitors temperatures to make sure they stay within comfortable limits. It communicates with the heat pump if temperatures do get too low.


According to the website of Kensa Heat Pumps, the Domestic RHI is intended for private self-builders and homeowners, acknowledging perhaps that you don’t simply fit a heat pump system into any old house. Currently the Domestic RHI pays out once a quarter for seven years. It pays out 20.46p per kWh with funding secure for new applications to 2020. The exact amount each applicant receives is worked out by an accredited installer. It involves the SCOP – seasonal coefficient of performance. This is the ratio of the energy the pump needs to work, to the heat produced.

An article on the website Homebuilding&Renovating, Ground Source Heat Pumps: Ultimate Beginner’s Guide, includes several photos of an installation, to give you an idea of what’s involved. Suffice to say, you need room for a digger.

Energy efficiency in the leisure sector

Olympic swimming pool in Tblisi

Leisure centres and sports stadia usually include big open spaces with lots of equipment. From olympic-size swimming pools to gyms, there are big spaces of heat and lots of kit to run. Aside from travel, venues often supply food and drink. Some provide showering facilities and treatments. There is the potential to use vast amounts of power and run up an oversize carbon footprint. We’ll be revisiting this subject so if you know of a good example or have a project to share please get in touch.

According to a Carbon Trust PDF, Sports and leisure, Introducing energy saving opportunities for business, energy costs are second only to staff costs for a leisure centre. At 30% of running costs this is higher than in most other sectors. In common with other sectors though are the trouble spots: heating, lighting and electrical equipment.

Simple measures

The Carbon Trust starts with recommending simple measures such as turning off equipment not in use, maintaining equipment, and planning energy efficiency refurbishments along with regular work. It goes on to look at how heating matches variable occupancy. This can be controlled through time switches and keeping it under review. It makes the slightly eye-rolly point that:

“Many systems function inefficiently becausesomeone made a short-term adjustment and then forgot about it.”

As buildings cool down slowly, the PDF recommends turning heating off an hour before the centre closes. These sound small and obvious, but they make a difference. Implemented in similar settings across the country would amount to a chunk off emissions.

Widely applicable

Much of the advice in the PDF is applicable to all sorts of buildings and businesses. It emphasises the use of natural light, making sure windows are kept clean. It recommends a revolving door to prevent cold air blowing in during the colder months. Sensor lighting is recommended for loos and little-used areas. A pool cover can reduce the costs of heating a pool by up to 30%. There isn’t a great deal about running a leisure centre that’s different to running any other type of setting, but with energy consumption so high there are many areas where improvements can be made.

Leisure Energy is company helping leisure centres make these improvements. Reading up on their work with Brecon Leisure Centre, not only do they design and project manage the works, but they check that the projected savings are being achieved. They also train staff in energy conservation. Without both of these measures, energy efficiency works run the risk of being a tick box exercise that don’t make nearly the difference that they could.

Works at Brecon included replacing a worn-out air handling unit kit with energy efficient model. As well as reducing energy consumption the improved unit gave the leisure centre more control over the function. Low energy lighting was installed. It saved money and improved light levels. This demonstrates that energy efficiency works often come with other benefits. Improving facilities while reducing emissions and maintenance, and saving money, is a win win win. Win.


Players warming up at Kingsholm, home of Gloucester Rugby

Rugby has been looking at how to improve energy efficiency and sustainability. There had been action on a case-by-case basis, but this was fragmented. Moves weren’t aligned, and results weren’t what they could have been. Last year, World Rugby published a sustainability framework. To quote World Rugby:

“Environmental initiatives included reassessing tender and host selection requirements for competition and event hosting. Guidelines were put in place to reduce/reuse/recycle signage, clothing and equipment, promote the use of teleconference facilities to reduce the impact of travel, provide cycle-to-work facilities and promote smart energy usage to create energy-efficient workplaces.”

On its website, World Rugby defines sustainability as “putting in more than you take out”, which isn’t a bad approach to life. World Rugby acknowledges that with a global game and international competitions, there is the issue of travel. It remains a work-on. There’s a willingness however to keep the game sustainable and to take steps to minimise its environmental impact in the areas where it can.

Its sustainability plan includes all the standard measures you would expect. Caterers are expected to avoid single use plastics, operate high standards of food sourcing with minimal food miles and reduce food waste. Players and fans are urged to travel light, cycle or use public transport. Best practice is urged in accommodation, eg re-using towels. 20 teams with 32-man world cup squads plus all the hangers-on, fans and officials adds up to a lot of towels. Teams are urged to double up in rooms (some do this already), and to stay near their venues to reduce travel.

Glasgow Warriors

These and more are however only suggestions. So are there any examples of teams really putting their backs into energy efficiency? Pro14 team Glasgow Warriors have promoted good practice at their stadium Scotstoun in several ways. Partnering with First Bus, fans can travel to the stadium for free on a matchday. Scotstoun is in a built-up area of Glasgow, so this reduces traffic and the associated emissions. It also helps to keep local residents on-side.

Rugby isn’t rugby without a pie and a pint. At Scotstoun most food packaging is compostable. See that? Compostable, not recyclable. The club wants all matchday food and drink packaging to be compostable or recyclable. The gound encourages recycling with colour-coded bins. The manager and players have been roped in to making videos encouraging fans to use the bins. 560 kilos of waste collected from just four matches alone was diverted from landfill.

MD of the Warriors, Nathan Bombrys, wants the club to be a positive influence on its home city.

Stadium design

Bankwest Stadium

In Australia, a new stadium will be powered by renewable sources. The Bankwest Stadium in Parramatta, a suburb of Sydney, has been built to LEED standards – leadership in energy and environemtal design. It will be lit by the lastest LED technology which will significantly reduce energy use. This is part of the New South Wales government’s policy of rebuilding major venues to climate proof them against extreme weather.

Antalya football stadium is Turkey’s first solar-powered stadium. 75% of the roof’s 16,000 sq m is covered in solar panels. These 6000 panels supply power away from the stadium when it’s not in use. Looking around at energy efficiency measures in stadia, solar energy pops up again and again. A multi-sport venue in Las Vegas, the T-Mobile Arena, is another using high-efficiency LED lighting. It also has energy efficient heating systems and has reduced its use of water and cooling energy. These measures together have won it a gold LEED certificate. It’s the first Las Vegas building to win one.


An article on the Selectra website looks at how much energy was used during last year’s football World Cup in Russia. In a 90 minute match enough power is consumed by a stadium to power at least 12 houses for a year. In a cold country such as Russia extra heating is used for keeping the pitch defrosted and in some cases to warm seats. FIFA has standards for even pitch illumination, which together with scoreboards and advertising accounts for 40% of the energy used in a game. Many of the 80,000 spectators want food and drink, so catering gobbles up another 20%. Broadcasting the match to the world takes 10%. Add in the power required for hordes of football fans to enjoy the match at home with cold beer and hot pizza, and the power drawn for watching just one football match is hair-raising.

Sitting in a stadium is the most environmentally-friendly way to watch a match, unless of course you’ve flown from the UK to Russia. The next best is to watch it in the pub – one TV, one setting to keep warm, one kitchen cooking the food.

Passive Cooling

Passive cooling is an element of low-energy building design. It works either by preventing heat building up, or removing it naturally. Natural cooling works by combining naturally-available energy and heat sinks – the sky, the atmosphere and the earth – with good design, rather than mechanical methods. Since 2000 the energy used to keep buildings cool has doubled, equating to almost the entire electricity production of Europe in 2016. Cooling is the fastest-growing end-use for energy in buildings.

Climate and microclimate are central considerations. Humid environments require something different from a hot and dry area. Humid places can be the hardest to cool effectively. In these cases many small openings in the building is more effective than a couple of large ones, to catch and optimise any breeze there might be. Some areas have a significant temperature change between night and day. Cool night air can come in at night and be trapped in during the day. Some countries are a similar temperature all year round, others have contrasting seasons. All this needs to be taken into account when designing the right passive cooling for any building.


Shutters on an Italian building

Shading minimises solar heat gains, while careful building layout and orientation planning will allow heat to build up where’s it most wanted. Orientation can for instance take into account the prevailing wind, to maximise breezes through the building. Insulation, usually considered in the UK to be about keeping heat in, can also keep it out by minimising heat transfer.

Shades or awnings can be retrofitted to almost any style of house to reduce solar gain in an overheating room. As they can be ‘out’ doing their job, or rolled or folded away at other times, they are a flexible approach that can be operated just in the rooms where you need them. Consider how often you see shutters on mediterranean buildings. They help to insulate in cold weather too, so maybe we’ll see them fitted more widely in the UK as summers get hotter.

Green roofs

A green roof on a modern house

A New Zealand website from the Ministry of Business, Innovation and Employment, Hikina Whakatutuki, provides lots of advice on passive cooling. It suggests painting the roof white to reflect sunlight, and insulating the roof space to prevent heat building up in the roof space filtering down into the house.

An alternative to a white roof is a green roof, or a living roof. A green roof consists of vegetation planted over a waterproof membrane. Some green roofs incorporate ponds to treat greywater, and others – not for the purist – include plants in containers. A green roof can be retrofitted to a house as well as incorporated into new build. They can be provide insect habitat, lower urban air temperatures and work against the heat island effect. Living walls do a similar job on the vertical. We’re trying something similar, in a small way, to cool our office. It gets the sun all afternoon and can become very hot and stuffy.

We’ve constructed a ledge around a chickenwire frame and put climbing plants in pots on the ledges. The idea is that as the plants grow they will shade the office. We’ve planted several varieties of peas and beans, as fast climbers, so we get a small harvest too. We’ll look more closely at green roofs and living walls another time, as they’re quite fascinating.

Fountains, ponds, planted pergolas and so on all make a difference.


Research has been ongoing in hot countries such as Chile and Malaysia into phase change materials (PCMs), including glycerine, wax oandwater. These absorb heat when the air around them is hot and become liquid, then emit it when the temperature falls and they solidify. There are all sorts of permutations of materials, temperatures and environments under research, but PCMs do look to have some effect.

Australia has been active in promoting passive cooling measures across all its zones. It recognises the enormous demand that can be placed on electricity when a heat wave hits and thousands of homes ramp up the air conditioning for a few days. There is a great deal of information available online from the Australian government, but one piece of advice leapt out:

“Conduction contributes to…comfort and involves body contact with cooler surfaces. It is most effective when people are sedentary (e.g. sleeping on a water bed).”

Energy Saving Product of the Week

Well after that, it has to be window blinds. Consider whether your blind is primarily to keep out heat or cold, or whether it does both at different times of year. Blinds can be metal, plastic, wood or cloth, slatted, vertical or horizontal. There are low-tech and hi-tech, internal and external.

If you’re struggling with keeping a room a comfortable temperature look at the role the window is playing in thermal gain or loss. Blinds can be professionally measured up and produced, or bought cheaply from a DIY shop. If you’re cooking in the summer and freezing in the winter, it’s worth examining how blinds could help.

What are we up to? We delivered new Petflap stock to the warehouse yesterday, including special orders. We continue to improve our range of photos, and will be including photos with added cats to our online galleries soon. If you’re wondering whether your cat will fit through the Petflap, do we have a treat for you! You can download a life-size pet access flap PDF from our site, cut out the aperture and see whether your cat or dog will fit through.

Thank you for listening to episode 7 of the Energy Efficiency Podcast, available through Apple Podcasts. If you like your podcasts with pretty pictures, a video version is available on YouTube – look for the Ecoflap channel where we also have product videos. Until next time you can find us on both Twitter and Instagram as Ecoflap, and on Twitter we also tweet under The Petflap. In next week’s episode we’ll look at green roofs, solar heating and energy efficiency in medicine. Bye.

Music credit: “Werq” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

Electric heating: The Energy Efficiency Podcast – episode 6

Electric Heating

Welcome to Electric Heating: The Energy Efficiency Podcast – episode 6, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.

Carbon capture machinery at a coal mine

Before we get on with our advertised features, we looked recently at the role of carbon capture in helping the UK achieve Theresa May’s net zero target. Carbon capture traps carbon as it’s produced, preventing it entering the atmosphere. The carbon can then be used to create chemicals required by industries including food (mm) and medicine. Last week, a division of the Indian-owned company Tata announced a new carbon capture project, the UK’s biggest, through a plant in Cheshire. It expects to prevent 40,000 tonnes of carbon entering the atmosphere each year, the equivalent of removing about 20,000 cars (what type of cars?) from the roads.

The plans are backed by the British government, which is contributing about a quarter of the £16m cost through a grant. An existing carbon capture trial at the Drax power plant in Yorkshire will receive a £5m boost, aimed at keeping 16m tonnes of carbon from the air by the mid-2020s. The government is helping to support nine carbon capture projects and supporting the development of a net zero industrial cluster in the UK by 2040.

The Tata project intends to use the removed carbon to create a high grade liquid carbon dioxide, used in creating baking soda. Sodium bicarbonate is used by pharmaceutical companies to make products including indigestion remedies and eye drops. Tata is the only company in the UK making sodium carbonate, which is used in detergent and glass manufacture. As Martin Ashcroft, head of Tata Chemicals Europe, points out, this carbon capture project helps Tata ensure a good supply of essential materials.

Tata is an enormous company with interests in many sectors. It owns one of India’s biggest energy companies, and has pledged to end investment in fossil fuel energy plants to focus on renewables instead. Realistically, it is behemoths such as Tata that have the influence and financial muscle to make changes the ordinary person can’t effect, so let’s hope that where Tata leads, on these issues at least, others will follow.

Electric heating

Last week we looked at gas heating, concluding that although it is cheaper per unit than electric heating and emits less CO2 than almost any other form of heating, it’s expensive and disruptive to install, an inherently risky material and, of course, a fossil fuel. Much natural gas production comes from fracking, particularly in the USA, which is widely accepted to be an environmental disaster.

electric heating
White electric radiator

In the UK, many houses that aren’t connected to the gas network instead use electric heating. About 4m households here don’t have access to gas, and of these about half use electric heating, so at two million households that’s a noticeable minority. Of these two million or so households, the vast majority use night storage heaters with the rest using plug-in fan heaters. A small minority of less than 100,000 households use heat pumps, which need electricity to run but are a whole subject in their own right and will be profiled next week.

Is it really more expensive?

Electric heating is more common in flats than houses, and homes using it tend to have a lower energy efficiency rating with the occupants on lower incomes, directly leading to fuel poverty. A report from Ofgem, Insights Paper on Households with Electric and Other Non-Gas heating, goes into deep but quite interesting detail on the demographics of electric heating customers, and how things will probably become worse for them financially over the next few years as tariffs and benefits become unbalanced and these customers are poorly-placed to take advantage of the best deals.

Electric heating is more expensive on a per-unit basis than gas, but installation is much simpler as pipework isn’t needed for a standard system with wall-mounted heaters. It’s straightforward to use or replace only part of the system. There is a reduced requirement for annual checks and maintenance, although not necessarily in high rise buildings and the rules are different on unvented electrical hot water systems, so an electric heating system can significantly outlast gas or oil systems. Given that effectively all houses in the UK have an electricity supply as standard, those paying the standing charge for gas on top have an extra charge.

Looked at as a whole over its lifetime, electric heating does not necessarily leap out as dramatically more expensive than gas or oil, but this might well feel different if you have inherited a system and/or are a tenant who is stuck with high electricity heating costs but doesn’t see the direct benefit of reduced installation costs and a longer system life.

Storage heaters

All electric heating is not equal. Most electric heating customers will have either night storage heaters, or controllable central heating. Night storage heaters, also known as electric storage heaters or just storage heaters, do what it sounds like they do – they store heat to disseminate later. Often this heat is built up during cheaper tariff hours, commonly overnight. This requires a particular circuit and meter, and the cheaper hours are dictated by the power provider. As the heat builds up in an element in the heater, it’s absorbed by high density material.

Standard models of storage heaters gradually release heat during the day, but there are smart fan-driven systems that retain nearly all the heat until it’s needed. Newer automatic and more efficient models absorb heat depending on the temperature of the room, and combination models can top up during the day using peak rate energy, if necessary. Since I last used storage heaters 17 years ago, the storage and control has improved from the already rather old clunky units that were hot when I didn’t want it, and cold when I wanted heat. Older heaters have a tendency to collect dust and dirt in their filters and fans.

Since January 2018 new storage heaters must comply with the European Ecodesign Directive, requiring them to meet a minimum energy efficiency of 38% for a heat output above 250W. This is in part what has driven improvements to storage heater design. The Ofgem report states that a proportion of night storage heater customers don’t feel warm enough. Together with complex bills easy to misread, and faulty equipment using too much power or producing too little heat, there are many complaints from electric heating customers.

Perhaps storage heaters are a useful addition to standard gas, electric heating or oil heating in a non-standard domestic set-up, eg a multi-phase building that doesn’t have central heating or gas heating fitted throughout. It could also present a cost-effective way of managing different warmth requirements, eg if someone ill or elderly wants their room warmer than the rest of the house finds comfortable, but without running an expensive fan heater. Ultimately the pro of storage heaters is that they are lower cost to run, drawing energy during off-peak hours. Basic models can still make a room uncomfortably warm, and it’s easy for all the heat to be used up by the evening.

Direct Acting Electric Heating Systems offer another option, and work well in properly-insulated homes that can be kept a comfortable temperature through far lower power radiators. These systems can be controlled in a way common to central heating systems, programmable to allow heat only in certain rooms and at certain times of day. Installing Direct Acting Electric Heating Systems to replace storage heaters in social high rises has reduced bills and allowed tenants to stop using back-up heat such as fan heaters.

Which has a page of impartial information on storage heaters.

Increased load

net zeroelectric heatingElectric heating systems in older buildings, multi-occupancy and high rise buildings face increased stress than a standard single-household building. When electrical systems were fitted in buildings dating from eg the 1970/80s and back, there was less overall demand on the electrical system than there is now. Increased use of power hungry domestic applicances together with wipespread use of multiple tech devices in the average home draw a great deal more electricity than would have been common in a house in the 1950s. Together with many older houses having poor insulation, an older building heated solely by electricity could become quite expensive to power.

Optimal use

As with the debate we referenced last week about gas heating, there is also disagreement about the best way to use electric central heating – keeping radiators turned off in unused rooms etc. Clearly it’s cheaper in simple energy bill terms not to heat a room that isn’t used, but could potentially-expensive damage be occurring to the fabric of the room? One argument in favour of the ‘always on’ approach is not wasting heat as a radiator heats and cools, but according to Robin Hood Energy,

“The energy expenditure require to maintain a steady temperature is greater than people assume, which is what makes the ‘always on’ option less efficient than it seems.”

Robin Hood Energy is an interesting organisation. On its website it describes itself as:

“Robin Hood Energy is the first not-for-profit energy company, owned by a local authority. We were set up to tackle fuel poverty and to help give people a cheaper, more helpful alternative to the Big Six. Launched by Nottingham City Council, we’re proud to be leading the way in trying to reduce fuel poverty for those who need help the most.”


Robin Hood Energy advises keeping as close a control over temperature in different rooms as your system allows. Often this is achieved by using valves – manual, thermostatic or smart. Manual valves are simply turned through a range of numbers like an oven dial – you stop when the valve is set to the temperature range you want for any given room. This controls how much hot water flows through and you are in charge.

electric heating
A thermostatic radiator valve

Thermostatic radiator valves, or TRVs, are set to the temperature you want the room to be. The system senses the temperature and opens or shuts the flow of hot water through the radiator accordingly. This has the scope to go haywire if your radiator is positioned in a cold or warm spot in the room or is influenced by other factors. If you’re considering fitting TRVs I urge you to read up on them, as much is said both in favour and against. The website has a page comparing different types of valves, and lists out what to consider with TRVs.

Lastly smart radiator valves. This connects to wifi and lets you control heating through an app. These can also connect with smart TRVs, in theory giving you close control of your heating wherever you may be.

Current electricity generation

So where does your electricity come from? Strides have been made recently in electricity generation in the UK, with renewable sources providing ever-increasing quantities of our power. A quick snapshot of power generation mid-morning on Tuesday 9th July shows that coal is producing zero energy, biomass 6%, solar, wind and hydro about 12%, nuclear 14%, and CCGT – combined cycle gas turbine – most of the rest. Business Green describes a combined cycle gas turbine as a system that:

“uses a gas turbine to create electricity and then captures the resulting waste heat to create steam, which in turn drives a steam turbine significantly increasing the system’s power output without any increase in fuel. The technology is typically powered using natural gas, but it can also be fueled using coal, biomass and even solar power as part of solar combined cycle plants.”

The National Grid describes its CCGT as powered by natural gas. At this moment we’re importing power from France and the Netherlands.

electric heating
Wind farm

Green electricity

It’s possible for a household to source electricity from a company that uses only renewable energy, commonly referred to as green energy. We use this for all the workshop and admin processes that take place on our premises, and as a family firm we power our home with it too. E.On has just announced it will be providing all of its domestic customers on all tariffs with 100% renewable electricity, at no extra cost. This will affect about 3.3 million customers. E.On generates a proportion of the electricity it supplies, and has contracts with wind generating firms in the UK. The remaining requirement will be sourced from 100% green electricity.

This comes on the back of a survey of 4000+ electricity customers not currently on a renewable tariff. 61% said they would switch to green power if it was available at a reasonable cost. There are all sorts of offerings using various permutations of tariffs, renewable energy matching, green funds, nuclear-free and so on, so if you’re interested in using less fossil fuel and supporting renewables, read around carefully. There’s certainly plenty of information available but it really behoves you to read the samll print. Listen to this cautionary note from the Energy Saving Trust:

“Many green tariffs state that your supply is 100% renewable. Some companies buy a mix of renewable and non-renewable electricity, but make sure that the amount of renewable electricity they buy is at least as much as the amount they are selling to customers through their green tariff. A few companies only buy renewable electricity, and so all their customers are on a green tariff. In either case, all the renewable electricity produced is supported by Government schemes that require electricity suppliers to buy some renewable electricity, and so it is difficult to say how much extra renewable electricity is produced as a result of signing up to a green tariff, even if it is with a 100% renewable supplier.”

It goes on to make the invaluable point:

“Green tariffs are no substitute for energy efficiency and you should always do whatever you reasonably can to reduce your current use of electricity and other fuels before considering spending money on a green tariff.” goes into detail about various suppliers on its website. There are quite a few, some long-established such as Ecotricity and many more much more recent. They have different visions and missions, so if you want to make the switch you should find a company that chimes with your financial and environmental priorities.

Electricity is a greener fuel, both in reality with fossil fuel use dropping in the UK, and in its potential, so from that point of view it is a preferable fuel to gas or oil. It’s usually simpler and cheaper to install than either gas or oil, with electric central heating less prone to problems than gas and without its inherent risks. If you’re in a position to pay the higher bills for electricity than gas, and particularly if your home is optimally insulated and draughtproofed, then electricity is likely to be the better option in most cases. For tenants and those reliant on storage heaters and/or pre-payment meters, the picture taken as a whole is less clear.

Insulation requirements for new builds

New development under construction

Building regulations exist to make sure that new buildings adhere to planning policy. In the UK this is carried out under the Building Act 1984 and the Building (Scotland) Act 2003, which affect new builds and aren’t usually retrospective. However regulations introduced in 2006 made it compulsory to upgrade energy efficiency in existing builds when extensions were built and certain other works carried out.

There was a total rewrite of the legislation in 2010, with numerous additions and amendments since, including some affecting measurement of energy and recognising the growing ways of heating and cooling buildings, imposing efficiency limits and requiring installation of energy use controls. Part L is titled “Conservation of fuel and power”. Kingspan Insulation explains insulation Building Regulations as follows:

“Building Regulations / Standards set the levels of thermal insulation required when carrying out building work, either for new build or refurbishment projects. These are expressed as a U-value which needs to be achieved. The required U-value will depend on the location of the project (England, Scotland or Wales), type of building (domestic or non-domestic) and the application (floor, wall or roof).” A low U-value is what you’re aiming for.

Wikipedia adds:

“Part L controls the insulation values of building elements, the allowable area of windows, doors and other openings, air permeability of the structure, the heating efficiency of boilers and the insulation and controls for heating appliances and systems together with hot water storage and lighting efficiency. It also sets out the requirements for SAP (Standard Assessment Procedure) calculations and carbon emission targets for dwellings.”

Zero carbon homes policy

Building regs specify minimum U-values, or heat transfer co-efficients, for building fabric. Tightening up of building regs means most new buildings will now include insulation, but this is a recent development. In 2016 there was a proposal to implement a “zero carbon homes” policy, first devised in 2007. The simple principle was that new builds wouldn’t make a net release of CO2. This would have had clear benefits to the householder in reduced bills, and to the environment with reduced emissions. First the proposals were watered down, then George Osborne scrapped them in the name of boosting housebuilding. According to an article on the ITV website, new build homes use more than twice as much energy to heat as a zero carbon home.

That was such a wasted opportunity to make a real difference, and begin our run-up to zero carbon that bit earlier. At the time the proposal was announced Britain was the only country making such a commitment. The proposals covered generating power on-site through renewable methods and implementing higher energy efficiency. Axing this proposal drew widepsread criticism from many quarters, including some closely involved in planning and housebuilding, who recognised what a step forward this would have been for the industry.

So how well do new builds perform?

Wikipedia describes UK insulation levels as low compared to the EU average. A study in 2004, admittedly a while ago now, claimed that 60% of new builds didn’t meet minimum standards, and of course any regulation is only as good as its enforcement. In 2006 a study for the Energy Saving Trust revealed that Building Control Officers often wouldn’t bother enforcing the rules on energy efficiency as it was considered low priority, but it would be nice to think that that figure would be far lower 13 years on.

In the summer of 2018, the government clarified that local authorities that wanted to could set higher energy efficiency standards than those laid out in part L of the building regs. It’s hugely encouraging that some councils want to set higher targets, and as usual, disappointing that the government won’t hold every council in the country to higher standards.

Despite this, improved building regs, building materials and methods, and a focus on energy efficiency, mean that a new build house is often going to be more energy efficient than an older one. Elmhurst Energy refers on its site to a Dept of Communities and Local Government report that shows 75% of new builds performing to A or B energy ratings, as opposed to 12% of non-new builds, but also notes a trend to slightly increasing energy consumption and CO2 emissions.

A Victorian house, an online resource supported by the House Builders’ Federation, just to give you a flavour of their agenda, has an interesting set of pictures and figures on their site comparing a new build to a renovated Victorian property. Obviously these aren’t the only comparisons to be made, and energy efficiency far from the only considerations of the quality and comfort of the environment, but it does seem to show much better energy efficiency in the new build.

However this is very much the rose-tinted view of the energy efficiency of new builds. The CCC’s recent report, UK housing fit for the future, highlights the gap between how energy efficient new builds are designed to be, and how well they actually perform. Interestingly it calls for an immediate enforcement of current building regs, suggesting things maybe haven’t improved all that much since 2006.

It doesn’t take much searching online to find lots of stories of owners of new-builds unhappy with many aspects of their new homes. There have been court cases, silencing orders and much misery. There are numerous stories of poorly fitting doors and windows, cracks and even holes appearing in walls and ceilings. Imagine trying to keep a house in that state warm and dry. In some cases inspectors have deemed new builds unfit for habitation. It’s hard to see how, in the current climate, this sort of thing won’t happen more often as the government drives through building vast quantities of houses. We won’t name and shame here, but a quick search brings up frequent comments from people involved in the construction industry who are horrified at the poor quality of building.

There is talk of creating a new build ombudsman, but surely drawing up tighter standards and enforcing them would improve matters for the owners of new builds? An interesting article on website Mortgage Strategy covers just these issues, highlighting lack of competition within the housing industry doing nothing to drive up standards and highlighting significant levels of unhappiness among new build owners with an inadequate complaints and redress system.

Dry lining

An article in the Guardian in February this year discussed the problems with dry lining, which is responsible for chilly homes that are pricey to heat. Dry lining is the process of fitting ready-made plasterboard panels to walls, instead of having them plastered in the traditional way. Dry lining speeds up plastering from a matter of weeks to days. It’s commonly used in countries that experience far colder winters than the UK and is not in itself a problem.

However thermal imaging has revealed how poorly plasterboard is often fitted, having a negative impact on airtightness. The Guardian article points the finger of blame at pressure on housebuilders to build fast, so care and time aren’t taken over fitting the plasterboard. Cold spots appear between the plasterboard and the masonry, reducing thermal efficiency. This doesn’t happen in older buildings that had wet plaster applied, and is one case where modern new-builds make energy efficiency promises over older houses that don’t actually come to pass. Some pre-1900 buildings can be more airtight than 2006 building regs call for now.

To improve matters some developers fill gaps with mastic or decorator’s caulk, a filler that often sets fast and can be painted over, but it deteriorates and may be removed from skirting boards completely when carpet is fitted. In 2017 a research paper was released by Dr Jenny Love and colleagues from the UCL Energy Institute, which chewed data from nearly 150,000 homes tested under the Air Tightness Testing & Measurement Association scheme (ATTMA). It came up with similar findings, and made this comment:

““The result of meeting the target through temporary sealing, which fails after a short time, is that for most of a dwelling’s lifetime, air permeability will be higher than the design value”

Again this raises the crux of the matter, that the maximum potential energy efficiency is nowhere near being achieved in most new builds due to shortcomings in construction. A spokesman from the ATTMA equated the amount of air leakage modern building regs allow for to a hole the size of a 20p piece in every square meter of wall, which is nonsensical for any setting making a pretence to energy efficiency.

A large part of the problem with enforcing the building regs such as they are is that regulations allow for sample testing. This literally tests a sample of homes, not every one, so many problems are missed. The Guardian article suggests that airtightness testing is carried out by people not properly trained to do it.

ATTMA considers that builders have no incentive to spend the little extra required to build properly and to standards, as building regs are so minimal in this area and poorly enforced. The article describes several new build case studies where poor fitting has led to the house being cold, draughty and expensive to heat. In one case a house profiled actually exceeded airtightness regs when it was built, according to the builder. Even if that was the case, why does these buildings’ thermal performance deteriorate so fast? Clearly we still have it all to do in this country to make any meaningful difference in energy efficiency in private housing developments.

Energy efficiency in social housing

electric heating
Social Housing

Social housing has traditionally been heated by electric storage heaters. Arguably the benefit of these has been felt more by the provider than the tenant, who is left with a clunky and hard-to-control heat source that they have little scope to change.

Decent Homes Standard

An article in Energy Manager magazine refers to the Decent Homes Standard, and holds it responsible for social housing providers leading the way with energy efficiency. According to the article poor housing is half as common in the social sector as in the private rented sector. The government has set high targets for the number of new social housing units required. The article quotes Martin Reed, MD of Elmhurst Energy who we referred to earlier:

““Social housing and local authority delivered about 33,000 homes in 2016/17, and therefore an increase to 150,000 a year for 20 years, to achieve the 3 million required, is a massive increase especially when you consider that the whole sector currently delivers approximately 280,000 homes. If the recommendation becomes reality, the house builders will need to build approximately 400,000 homes per annum, 42% more than today. What is important is that the mistakes of previous booms are not repeated. These new homes must be built to the highest standards of quality and energy efficiency to ensure that the future tenants don’t become the fuel poor statistics of the future.”

That’s very interesting given everything said just now about new builds’ real energy performance.

The Decent Homes Standard is described by wikipedia as “a technical standard for public housing introduced by the United Kingdom government”.

The four criteria for the housing are that it:

be free from any hazard that poses a serious threat to your health or safety
be in a reasonable state of repair
have reasonably modern facilities
have efficient heating and insulation

Clean Growth Strategy

A couple of years ago the government announced the Clean Growth Strategy as part of its efforts to meet its own targets set out in the 2008 Climate Change Act. Part of this is a target to get to get all housing up to Energy Performance Certificate (EPC) Band C by 2030. The government expects this to be achieved in part by increased uptake of renewable technologies but also replacing dirtier fossil fuels with cleaner ones. Broadly the Clean Growth Strategy has been positively received. Social housing has made improvements in energy efficiency and considered among the most energy efficient housing in the UK, but there’s massive scope to do more.

Of course this is constrained by the limits social housing providers can place on rents, but long-term budgets exist for upgrading properties. Social housing providers have long recognised that tenants not struggling to pay fuel bills are better able to keep up with the rent, so the economic case for energy efficiency is made. Grants and programmes exist to support social housing improvement, especially to improve the worst performing stock. Although feed in tariffs have been hit recently, incentive schemes have prompted providers to install solar panels. At scale, this is still worth it.


Long term, housing will need to hit better than band C for energy efficiency. Social housing providers could get ahead by improving to better than band C from the off, especially given that they will own their housing stock for many years to come. Aiming for zero carbon is a lot to ask, but makes a great deal of sense. One way to achieve this is through Energiesprong. Energiesprong is a combined funding and building model that describes itself thus:

“Part of the innovation is how the works are funded. The household pays an ‘Energy plan’, and the landlord (NCH) receives an on-going income to fund similar works to more homes. The resident has a much more comfortable home, and a flat rate cost for energy, which will not rise significantly when energy bills rise.”

Crucially it guarantees that the work will perform as advertised, something the regular UK construction industry is signally failing to do just now. Work takes place in just a matter of days, and has been put into practice in the British social housing sector. The work comes with a 30 year warranty. Energiesprong works in many countries including the Netherlands, where it has been particularly successful, the USA, France and Germany.

A number of projects have taken place in the UK, including retrofitting 10 homes in Nottingham as a pilot. The homes were wrapped in a prefabricated wall with solar panels on top. This is part of a wider approach by Nottingham council to improve energy efficiency in its properties across the city. London, Essex and Devon all have plans for Energiesprong works.

In Scotland social housing providers must abide by the Scottish Government’s Energy Efficiency Standard for Social Housing (EESSH), meeting its standards by 2020. Using the Energy Efficiency Hierarchy method, providers look at the right solution for a house or flat by first assessing the property for fitting cavity, internal or external insulation to reduce energy needs, fitting new energy efficient heating system to use energy more efficiently, and lastly fitting renewable energy technologies such as PV panels.

Energy efficiency refurbishment

In Norwich a development of 105 passivhaus homes has been built. This is one of the largest energy efficient schemes underway in the UK. A report on the Science Direct website highlights great potential to improve energy efficiency in social housing in emerging countries such as Brazil. Emerging countries have a high energy demand, which energy efficiency in social housing would help to reduce. In Denmark the Frederikshavn Housing Association in northern Denmark is refurbishing nearly 300 homes to a high energy efficiency standard. It’s also investing in renewable technologies integrated into the building. Their target is a 30% energy saving. They’ll achieve this through improving the building envelope, using less energy hungry lighting systems, fitting HVAC and upgrading windows, and providing tenants with smart energy monitoring systems.

A report from the Department for Business, Energy and Industrial Strategy looks at the barriers to retrofit in social housing. It found that moneys for these works are separate from the routine maintenance budget. As each has different contracts set up to deliver, it can be difficult to co-ordinate works. Ignorance is another problem. A great idea on paper can meet problems on the ground when a housing provider or its suppliers don’t really grasp the detail of what’s required. Limits on funding and staff cuts pose more problems. Both of these issues push energy efficiency retrofit behind more urgent works such as bathroom and kitchen replacements. The report is available as a PDF download and is food for thought.

Essentially, upgrading social housing to or beyond the minimum standards required is a win for the tenant. It also protects the landlord’s investment. However it costs money, and the research and planning time must be prioritised by the provider if much is to change beyond a handful of exciting projects.

Energy saving product of the week

This week we’re looking at saving power in the office. If you’re already keeping your phone charged with a solar charger, you can team that with a solar-powered keyboard. Logitech is the main manufacturer of these. The K750 has PV cells on its top edge and will charge in sunlight or artificial light whenever it detects it; you don’t have to think about topping up the charge. The keyboard makes various other claims about being wonderful which is great as it retails from Logitech for £80.

electric heating
The Petflap on red

What are we up to? We delivered new Petflap stock to the warehouse last week and are now working on new regular stock and special orders. We’ve had part of our photo shoot, with more to come over the next week or two. We’re looking at better ways of creating our trunking and progressing with a third party to keep up a steady stream of parts. We’re happy to answer as many pre-purchase questions as anyone can ask. Don’t hesitate to get in touch if you have a Petflap query.

Thank you for listening to episode 6 of the Energy Efficiency Podcast, available through Apple Podcasts. If you like your podcasts with pretty pictures, a video version is available on YouTube – look for the Ecoflap channel where we also have product videos. Until next time you can find us on both Twitter and Instagram as Ecoflap, and on Twitter we also tweet under The Petflap In next week’s episode we’ll look at ground source heat pumps, energy efficiency in the leisure sector, and passive cooling. Bye.

Music credit: “Werq” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

Gas heating: The Energy Efficiency Podcast – episode 5

Gas Heating

gas heating
A Tesco supermarket

Welcome to Gas Heating: The Energy Efficiency Podcast – episode 5, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.

This week: gas heating, where to start with draughtproofing your home, and energy efficiency in self build. Before we get on with our advertised features, the Guardian recently ran an article suggesting that supermarket fridges could form a nationwide virtual battery for the National Grid. Research in a mocked-up supermarket, undertaken by Tesco and the University of Lincoln, shows that electricity can be provided in short bursts to the grid by briefly stopping power to supermarket fridges. Power is already turned off to the fridges each day to allow for deforsting, and the proposed system would replicate this. The power wouldn’t be off long enough to affect the food, but the top-up power could help balance a dip in the grid’s energy supply.

The Guardian article quotes Professor Simon Pearson of the University of Lincoln:

Cold food is, in fact, the UK’s largest battery. There is sufficient ‘cold energy’ in the food to keep a refrigerator cold if the system reduces power for short periods to help offset power shortages on the National Grid.”

The National Grid already operates this type of system with companies that own utility-scale batteries. Increasing the scale of the operations to include a nationwide supermarket chain increases capacity while helping supermarkets reduce their carbon footprint. Commercial refriferation systems make up about 12% of the UK’s carbon emissions, with energy bills accounting for 1/3 of costs for a typical retailer. This is one example of technology helping the UK to reach its net zero target.

Gas heating

gas heating
An oil tanker delivering to a rural area

Last week we looked at district heating networks, concluding that they were more energy efficient than heating produced by individual boilers, and ideally produced their heat from renewable sources or waste heat. This week we look at mains gas heating. Wikipedia defines natural gas as “a non-renewable hydrocarbon”, describing it as “a major cause of climate change” both in itself if it leaks, and because of the CO2 emitted when it’s used.

Widely available

Gas heating is far more widely available than district heating, but it isn’t available everywhere. Rural areas tend to be less likely to be connected to the gas network, so oil is a more commonly used fuel in the countryside. OVO Energy states that 3.9million homes in the UK are without gas heating, and Citizen’s Advice Scotland quotes a figure of 46% of households in Wales without access to gas.

In the UK the average gas-connected home is built from the 1950s, and average off-gas home up to the 1930s. Of gas-connected homes, over 75% are within bands A-D of the Energy Performance Certificate rating, ie the best-performing four bands.

8 million gas boilers are sold in the UK every year. Simply, they heat up water to pump through pipes to radiators and provide hot water to kitchen and bathrooms. According to Rointe, suppliers of electric heating infrastructure, gas heating systems haven’t changed much over the years. They tend to be more expensive to install than electric systems, being more complex, and don’t last as long. Gas heating comes with the risk of carbon monoxide leaks and burst pipes, and is the UK’s biggest greenhouse gas emissions source.

Cheap to use

The Energy Saving Trust describes gas as usually being the cheapest form of heating fuel available, and having the lowest CO2 emissions apart from wood. OVO has pulled together data on energy prices and the energy efficiency of the most commonly used forms of fuel, and presented them as a graph on its site. Gas comes out as the cheapest, electricity the most expensive. That graph is on a very useful page that gives a comprehensive run down of the different forms of fuel generally available and what a household can do to maximise them, so it’s very well worth a read if you’re considering a change or an upgrade.

Gas produces lower CO2 emissions as it is’clean burning’, ie it produces fewer undesirably by-products. When used to generate electricity, gas produces about half the emissions of coal. It is also a more efficient fuel than coal, but it’s all relative. A coal burning plant is around 30%+ efficient, whereas a gas-fired one is around 43% efficient. It’s not great, but it’s better. In plants that use waste heat from a gas turbine to power a steam turbine, known as a natural gas combined-cycle, efficiency leaps to as much as 60%.


Gas is such a popular fuel in the US due to its lower CO2 emissions, the speed with which gas plants can increase or decrease production in response to available quantities of wind and solar power, and its low price.

gas heating
A shale gas extraction plant in the USA

In America, virtually all natural gas is produced domestically, mainly in Texas, Pennsylvania and Louisiana, and exported to Mexico and Canada. It was discovered originally as an unwanted by-product of oil production. The US is the world’s largest producer of natural gas, passing Russia 10 years ago. An ample supply in America brings prices down to much lower than in Europe and promoted natural gas in electricity generation.

It’s worth noting however that shale gas is now a key source of natural gas in the US, which is a controversial subject both there and in the UK where its extraction is known as fracking. Fracking is blamed for earth movements and contaminated water supplies, among other things, and as part of the fossil fuel industry its operation is unpopular in the UK in particular.

In the EU as a whole, the use of gas is declining slowly. Gas-fired power plants that used to run continuously now tend to run during peak times only. A report from the European Energy Agency suggests that warmer winters are reducing the call on gas in the winter, and that renewables are stepping in to make up ever larger quantities of the heating power demand. However outside the EU, and not just in America, the use of natural gas is increasing.

So how do you use gas heating efficiently? Really it depends where you look for advice. There is a theory that the boiler is best left on low all the time, but another that you should use the heating only when you need it. Another belief is that radiators should be set to a very low temperature or turned off in rooms seldom used, but that argument is countered with the suggestion that the fabric of the room will deteriorate.

Getting the best from any particular gas-fired set-up means understanding the specifics of your system – your boiler, your radiators, your house, your habits, your budget – and being prepared to tweak the system to get it right for your comfort and the house’s fabric. There are a couple of web pages looking at the ins and outs and whys and wherefores of all this, Money Saving Expert and Ask Jeff. There’s a wealth of information available on both.


Reading up on the nuts and bolts of gas heating, it comes over as a clunkier system to use than eg electricity. Heating up just one radiator requires the system to be activated as much as heating the whole house, and gas boilers are at best 90% efficient. It can be less easy to control heat levels in different parts of the house. There’s no getting away from the fact that gas is a fossil fuel, so even the newest and most efficient systems are still running on a fuel that has really had its day. Although cheap to run on a per-unit basis, installing and maintaining a gas system can be expensive and invasive, and running it comes with ongoing risks. If you’re looking for the most energy-efficient form of heating, gas wouldn’t really be in the running.

According to a report from the CCC, more or less all homes currently running on or connected to the gas network would be suitable to switch to hydrogen heating or a heat pump, but barriers to fitting these include upfront costs and the suitability of the home itself (heat pumps need to be connected to energy efficient buildings in order to perform well). The CCC report, titled Heat in UK Buildings Today, is suprisingly interesting if a bit technical and wordy.


The report points out that the 23 million homes currently connected to the gas network account for a walloping 77% of total UK heating emissions. The CCC wisely points out that these homes may have other issues affecting their performance, such as lack of cavity wall and loft insulation. Fitting these would reduce the heating needs and thereby help to tackle fuel poverty and reduce carbon emissions. It emphasises the scope for energy efficiency in new builds, stating:

” While the energy efficiency standards for new homes have increased substantially over the recent years, low-carbon heating sources are not required in new homes.” We will be looking in a future episode at the insulation standard required in new build homes constructed by mass building commercial outfits.

The report presents the rather sad finding:

“More generally, there is evidence that households typically do not think about heating, associated emissions, or what heating system they use, as long as it is delivering the expected level of comfort and it is considered financially affordable.”

This being the case, energy efficient heating systems need to be baked in as widely as possible so that what households aren’t thinking about isn’t doing any more damage than is unavoidable.

Where to start with draughtproofing your home

Or you might ask, why draughtproof your home? To echo the CCC’s point in the last feature, reducing a home’s need for heating has benefits all round. The bills go down, the home is more comfortable, and there is a reduced need for whatever fuel is being used to provide the heat. It’s also good for the fabric of a building, but consider the difference between draughts and ventilation. Ventilation is needed, controlled and welcomed, draughts aren’t.

So where do you start? If you haven’t already listened to our feature on draughtproofing historic buildings you might find it useful to do so now, as there can be quite a bit to consider.

Open doors

First you need to understand your home and your habits. I knew someone who left their back kitchen door open 24 hours a day so that the dogs could come and go freely (if only we’d had the scope then to provide them with a dog-size Petflap). Draughtproofing the kitchen windows isn’t really going to help if the door’s open all day, but paying attention to the space between the kitchen ceiling and the floor of the room above could pay dividends. I knew someone else in a damp home who kept the heating on low 24 hours a day and opened windows so that the house stayed a comfortable temperature. Draughtproofing rooms where the windows are always open wouldn’t be the best use of budget – better instead to address the dampness.


So once you know where the draughty spots are in your house you can tackle them. If you heard episode 2, Passivhaus, you’ll have heard about the C.H.E.E.S.E project in Bristol that offers affordable thermal imaging to identify cold spots in a building. Common trouble spots are poorly fitting doors and windows, draughty letter boxes and pet doors (our company started in response to just that problem), but pay attention also to, for instance, where cables go through walls. Any vents should be left unblocked, but you can open and shut them when needed. Be aware too that some rooms need very good ventilation as they can become steamy – the kitchen and bathroom are obvious places, and a utility room if you have one. Anywhere with a flue or open fire also needs good ventilation.

As the temperature drops it’s easier to feel where draughts come in, but be sure to distinguish between windows that just aren’t very insulating, and windows that have actual draughts coming in around them. If you aren’t planning to replace draughty window units, then fitting a sealing tape or strip around the draughty part of an opening window will help to block draughts. Check it doesn’t impede the action of the window so you can still open it. A non-opening window can be draughtproofed with silicone sealant.


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A curtain over the door helps to block draughts and keep your home cosy

Doors are quite easy to draughtproof. First check whether the door itself fits its frame snugly and address any problems there. The next three steps are dealing with a draught coming in under the door, through the letterbox and through the keyhole. Draughts under the door just have to be blocked, if replacing the door or permanent remedial works aren’t feasible. A good old-fashioned door sausage helps, as will a curtain. Your granny probably had a door sausage – mine did, complete with fabric ears and nose to turn it into a sausage dog – and they’re simple to make if you fancy a wee project.

A curtain is a good idea no matter what, as it will make the area around the door more cosy once temperatures begin to fall. There’s something quite primitively comforting about locking the door and pulling across a snug curtain, on a cold, dark night.

Depending on the design of your door’s handle and lock, you may be able to fit a cover to your key hole. Try to use a material that insulates, rather than a metal which will conduct cold air.


Lastly the letterbox. Consider three things here: the fit of your letter plate, the action of your letterplate, and what you fit to prevent or block draughts. A letter box aperture is just a hole through the door, and to ensuree that draughts don’t whistle in round it, the letter plate needs to fit snugly. That’s the first thing to check.

Secondly, check the action of the flap in the letter plate. Does it stick? Does it fit the gap properly? If it sticks, try making sure all the edges are clean – depending on the material this might need a damp cloth, or brass or steel cleaner and a SOFT cloth – then see if the action improves.

If the letterbox is in really poor shape look at replacing it. These days fewer people have giant wads of newspaper delivered through the letter box and the chunky Yellow Pages is a thing of the past, but large deliveries being stuffed through the average letter box can cause damage.

If you still suffer from letter box draughts, you need a draught excluder, a unit that fits on the house side of your door and performs in one of several ways to block draughts. Sometimes these are brushes, sometimes magnetic strips, but anything of this ilk provides a barrier to post as well as of sorts to draughts, and can result in damage to the letterbox as the delivery person rams post through the obstructions. The Ecoflap lifted at the merest touch of a pizza shop flyer due to a widget, yet beccause of the way the flap was cut would stay shut and not rattle in very stiff winds. It will be replaced by the Letterplate Eco, an external draughtproof letter plate that works on the same principles.

Pet doors

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The draughtproof Petflap

Approach your cat flap in the same way. This is used, potentially, many more times a day than a letterbox so all the same considerations apply but tenfold. If you don’t have a pet then consider sealing the cat flap. If the problem is simply that cold air comes in around the pet access flap and there is no insulation to the unit, consider upgrading to a draughtproof Petflap. It works on the same principle as the Ecoflap, blowing more firmly shut against its frame in a draught. It also has 12mm of material between your house and the weather outside, providing insulation against cold weather.

Also in episode 2 we mentioned the Chimney Sheep, a sheep’s wool chimney blocker that prevents draughts coming down the chimney while still allowing the house to breathe through the chimney. Obviously this needs to be removed if and when you use the chimney, but, especially if you have chimneys you never use but don’t want to block up, this is a great solution to an obvious and large draught risk. Loft hatches are another large draught hazard so apply strip insulation round there if need be.

Many of us have cables coming into the sitting room to deliver digital services. It’s not unusual for draughts to creep in round the cable, and we even had ants come in through ours once, so pay attention to anything like that and block the gaps. The same applies to pipes, but be aware of what the pipe is used for and how it might behave in hot, cold or freezing weather.

These measures are small, but there’s good value to be had from checking these areas. It’s possible to spend a great deal of money on insulating your home and installing high-performance hardware, but if draughts can still come in in all the old places then the job isn’t finished.


Once the small jobs are taken care of, consider next how much cold air comes up through the floor and round the edges of the room. Floorboards need to be flexible so make sure any measures employed take that into consideration. As well as filling gaps, feature floorboards can be covered with a rug when it gets particularly cold, if you want some temporary extra cover.

A very useful page on The Energy Saving Trust – no episode complete without a mention – mentions old extractor fans. If they’re no longer in use they can be filled and sealed at each end.

If all of these spots are checked and dealt with, your home should be that bit more comfy, cosy, and cheaper to heat come the winter. An article on the Homebuilding&Renovating website claims that many of these simple measures can pay for themselves within a year, but that’s very much dependent on individual circumstances. A page on the Which website goes into detail quantifying savings.

Lastly, it’s worth investigating whether you’re eligible to take advantage of a funding schemes. There are groups and councils all over the country, in fact all over the world, offering free and subsidised good and services to draughtproof homes, so a little while spent searching for something in your area could pay dividends.

Energy efficiency in self-build

Self build is a huge area, itself the subject of dedicated podcasts including Ben Adam Smith’s House Planning Help. Planning a self build is the perfect opportunity to design in energy efficiency measures that the house will benefit from for years to come. Your plans are bound to be constrained by something: planning position, location, budget, finding the right architect and builder or even your type of mortgage. Unless you yourself are the eco build expert, then it’s worth putting yourself in the hands of someone who is. That’s the technical, project management and compliance bits taken care of, but the decisions will come down to you.

Fabric First

Firstly you need to decide how far you’re taking your energy efficient build principle, what does the phrase mean to you? Reusing materials? Upgrading and expanding an existing building on site? Building a Passivhaus? What is common to most eco builds is a ‘fabric first’ approach. What is fabric first? Kingspan Insulation defines it as:

“maximising the energy performance of the structure itself through the components and materials making up the building envelope. This is before renewable mechanical and electrical building services are considered.
In other words, constructing your building to save energy for you before renewable technologies are factored in.”

In other words, the house itself is designed and constructed so that it’s already performing at a better level of energy efficiency than a regular build, before goods and services are taken into account. This really has to be the first principle of an eco build, and it can be achieved in many ways, including through the innovative use of ancient materials, such as straw bales and sheeps wool insulation.

The website LoveProperty has a page on straw bale construction, featuring homes including Strawbale Getaway in Colorado, The Gatehouse in Dumfries and a house in Zoermeer in the Netherlands. These are fascinating projects and well worth a read.

Sheep’s wool

Sheep’s wool is not only insulating but provides a sound baffle and acts as a moisture buffer. It has an insulation value unmatched by any other material, according to the website, which provides sheep’s wool insulation to the building industry. As well as loft and wall insulation they provide underlay, cylinder jackets and even slippers, so you can get the full sheepy experience.

Prices for sheep’s fleeces have been very low in recent years, so given the work involved in processing and marketing them they haven’t been valued. This changing now, with wool being promoted for insulation but also for all sorts of other products including duvets and coffins. Sheep’s wool was used recently in Manchester to insulate historic buildings, sourced locally to reduce the shipping miles. We think of this as new and exciting, but sheep’s wool insulation has been used in one form or another for generations. Not only does it keep you warm in the winter, but it keeps you cool in the summer, so you almost have to ask why an eco-build wouldn’t consider it for insulation. There are of course many other options for the building materials, including high-performance prefabricated panels.


An energy efficient self build will pay close attention to airtightness. It’s going to be a high priority. We receive many enquiries from people building energy efficient homes with very thick walls, who want to put in a cat flap with trunking that reaches right through. We can do this happily. We’ve recently received two enquiries for walls 60cm thick, which indicates just how much insulation can be fitted into a wall.

A page on the website goes into detail on how well various wall materials perform on airtightness and is a good place to start if you’re doing some research. They make the point that whatever you go for, airtightness and insulation go together so make sure they both feature.


Windows are crucial to the success of an energy efficient home. Get it right and you’ll get a beautifully light home, keeping your lighting costs down and benefitting from the warmth generated. The problem can be that large areas of glass that conduct heat into the house in the daytime (known as solar gain) can swiftly conduct it right back out again after dark. Triple-glazing can help to address this. There is also the balancing act between getting the benefit of the warmth and not overheating.

Achieving the right balance for you will require technical help and the best performing window units your budget will run to. This podcast from Mottramm Architects in Maine covers all the considerations of choosing windows to complement an energy efficient build.

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Solar panels on a house


Once your home is built from high performance materials, you’ll need to power it. Are you going to fit your own energy generation systems? Even if you’re not fitting PV panels for instance, or a heat pump, you’ll likely be installing energy efficient heating. In this instance underfloor heating is a popular choice.

Mechanical Ventilation Heat Recovery systems recycle heat that would otherwise be lost. They tend to be a requirement of passivhaus certification, but you don’t have to be building a passivhaus to benefit from MVHR.

It goes without saying that any build aiming for a high standard of energy efficiency will easily surpass current building regulations (we’ll take a look at building regs in a future episode). As with home draughtproofing measures and depending on the nature and scale of your self-build, it’s worth investigating if there are government schemes where you live that might help with the cost of an energy efficient boiler, or fitting loft insulation.

For inspiration, why not look at the Grand Designs web page on energy efficient self-builds? It features seven builds, from agricultural housing to extended period houses to glossy new builds. See what can be done in all sorts of locations from a lochside to a forest to the Sussex suburbs.

Energy saving product of the week:

Gas heating
A solar charger in use

This week’s energy saving product is something you might want to get your hands on with a spell of sunny weather coming up – solar chargers for mobile phones. These use solar power rather than mains power to charge not only phones but tablets and laptops. There are quite a few to choose from and while none of them are quite ready to replace a standard mains charger, that doesn’t mean you can’t benefit from using direct sunlight.

Chargers come in battery form and direct charge form. The battery type stores the energy its solar panels create, giving you a back-up if you’re nowhere near a charging point when your phone runs out of juice. The direct charge type pump the energy they create straight into a device plugged into it, and doesn’t store it for later use. Both have a role.

The units tend not to be cheap – £50 isn’t unusual – so if a solar charging unit appeals to you take a look at the website for a rundown on what’s available.

What are we up to? We’re still making our next batch of Petflaps and progressing with our photoshoot, none of this helped by illness sweeping through the team. We’ve also upgraded our shopping cart so buying from outside the UK is now a simple matter.

Thank you for listening to episode 5 of the Energy Efficiency Podcast, now available through Apple Podcasts. If you like your podcasts with pretty pictures, a video version is available on YouTube – look for the Ecoflap channel. Until next time you can find us on both Twitter and Instagram as @Ecoflap, and on Twitter we also tweet under @The Petflap In next week’s episode we’ll look at electric heating, energy efficiency in social housing and insulation requirements for new builds. Bye.

Music credit: “Werq” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

Net Zero: The Energy Efficiency Podcast – episode 4

Net Zero

Welcome to Net Zero: The Energy Efficiency Podcast, episode 4, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.

This week: net zero, tenants’ rights to energy efficiency works in their homes, and district heating. But before we get on with our advertised features, at the end of last week the UK press was reporting the National Grid’s prediction that zero carbon energy sources will provide more than half the UK’s energy in 2019.

Coal-fired power is declining, replaced by clean sources of power such as wind, solar, hydro and nuclear. So far this year coal-fired power has generated only 3% of power, whereas renewable eneergy has leapt from generating just 2% to 20%. This comes on the back of Britain’s longest stretch of coal-free power generation recently, equivalent, according to a Guardian article, to preventing 5m tonnes of CO2 being release into the atmosphere, the equivalent of a staggering 12bn miles driven in a car.

The government plans to phase out all coal-fired power generation in just six years from now, so the Natinal Grid has the job of ensuring other sources can replace it. It is spending over £1bn a year to adapt the grid for all renewables.

Net Zero

net zero
Carbon capture technology at a coal mine

Net zero is in the news every day just now it seems – so what is it? According to the LSE’s Grantham Institute on climate change and the environment, net zero refers to emissions produced and emissions removed from the atmosphere. This can be achieved by reducing the emissions, extracting carbon, or a bit of both. The Grantham Institute draws a distinction between net zero, and gross-zero:

“In contrast to a gross-zero target, which would reduce emissions from all sources uniformly to zero, a net-zero emissions target is more realistic because it allows for some residual emissions.”


There are many permutations of how to achieve net zero. Simple tree-planting can help as trees absorb carbon dioxide. A positive knock-on from this is increased habitat for creatures of all sorts and an enhanced landscape, but this is a slow process. An article from Left Foot Forward claims that tree planting alone could deal with a third of greenhouse gas reductions needed in the next decade. This is the subject of political pressure for increased funding and government attention. Encouragingly, the CCC recommended a huge programme of reforestation and peat moorland restoration in its recent report on net zero.

Carbon capture

Technology has a huge role to play, most prominently carbon capture and storage. This in theory permits the continued burning of fossil fuels. The carbon is compressed to a liquid state then pumped deep underground into now-empty coal mines, gas reservoirs and so on. This system can capture up to 90% of carbon released from burning fossil fuels in electricity generation and some industrial processes.

Direct Air Capture removes CO2 directly from the air, converting the oxygen and storing the carbon. This type of system is used in sealed environments such as submarines and space craft, but it’s difficult to make economical at scale. As usual, there is the need to make a business case for developing technologies, creating a market for so-called ‘negative emissions’. An article on Business Green suggests that this can be achieved through a government-run system or regulated market.


Emissions cannot be removed completely. The CCC estimates 130 million tonnes of carbon dioxide-equivalent will still be emitted even with current technologies maximised, mainly from industry, aviation and shipping, and agriculture. Offsetting seems to be the only way to deal with these, at the moment. The Grantham Institute explains this as:

“By having another country plant more trees or use negative emissions technologies, this reduces the amount of emissions globally, so countries may wish to use this to achieve their net-zero target.”

Clearly this strategy has its limitations, ie we can’t all do it, and for this and other reasons offsetting is controversial. So far Costa Rica is the only country that believes it can reach net zero without offsetting.

net zero
Aviation would see some of the steepest price rises

So how does the rest of the world reach net zero? One theory is that schemes imposing fines on the worst polluting industries would provide an imperative to reduce emissions while generating revenue to help fund negative emissions research and systems. The CCC’s recent report suggests differing and increasing prices for carbon, with industries such as cement and steel production and aviation seeing some of the steepest rises.


All carbon-creating travel would become more expensive with fuel duty and flight prices increasing. Industry wouldn’t welcome these price rises, already accusing carbon prices of undermining its competitiveness. The CCC recommends combining this with targetted policies to ensure the worst-off households were protected, eg through more funding for energy efficiency measures in fuel-poor homes.


Achieving net zero is a very difficult ship to steer. Business and industry wants to protect itself but recognises it can’t carry on as it has. Incentives have to exist for the development of new technologies. Concerned populations want to see progress but not be deprived of too many features of modern life. Governments have to be seen to do something while not squashing the sectors it needs for revenue and support. There are different approaches around the world.

Bhutan is currently carbon negative as it has a population of less than a million and little industry. It aims for carbon neutrality, likely achieved through using its natural resources to generate power, but this will need to be balanced against a rising demand for cars in the kingdom.

Chile plans to close 28 coal-fired power plants in the next five years and phase out coal altogether by 2040, aiming for net zero by 2050.

Denmark is targetting cars, banning sales of new diesel and petrol cars by 2030 and hitting net zero by 2050.

Finland aims for net zero by 2035, targetting industrial logging and phasing out peat burning for power generation.

Iceland plans to phase out fossil fuels, plant trees and restore wetlands. Iceland uses renewable geothermal and hydro power so generates very little carbon through electricity production.

Scotland is basing its plans on its strong renewable energy resources and storing CO2 in depleted North Sea oilfields. It has a number of plans to go as far as it can while still attached to the UK, including reducing VAT on energy efficiency improvements in homes.

Uruguay is likely to become a net carbon sink by 2030. Uruguay is increasing forest cover and reducing emissions from farming, waste and energy.

Thank you to the website for that global rundown.

Tenants’ rights to energy efficiency works to their homes

net zero
Typical pre-1919 UK housing

In April 2018 legislation came into force requiring landlords to improve the draughtiest homes in order to agree new tenancies. Homes in bands F and G, the lowest-performance rating, must now meet band E minimum. The same regulations will affect all tenancies, new or existing, from April 2020. There will be a civil penalty of £4000 for any breaches. The government aims for all privately rented homes (note that specific phrasing) to meet band C by 2030.

In 2018 the cost ceiling was put at £2,500, but the government will now tighten up this legislation. It was designed to protect landlords from significant up front costs on work such as insulation. Now increases in the up front cost threshold to £3,500 exempt fewer landlords from carrying out works. This higher level is expected to come into force this year.

Low-rated homes

According to an article in the Guardian, there are nearly 300,000 F- and G-rated homes in England and Wales. The government expects works on houses in these bands to save tenants about £200 a year. There is widespread criticism from tenants’ interests groups and climate campaigners, claiming that a ceiling of £5000 would have lifted 40,000 homes out of fuel poverty and discomfort.

Green Deal

In April 2016 domestic tenants acquired the right to request to carry out energy efficiency improvements to their properties, with the landlord unable to reasonably refuse permission. The tenant was expected to pay for the work with no upfront cost to the landlord. At the time that covered improvements eligible for Green Deal loans, the idea being that money paid out for works was repaid directly through energy bill payments. From 2013-2015 the government supported the Green Deal Finance Company, and after that support stopped some private companies stepped in to support it instead. In 2017 this privately-backed scheme began offering loans.

Works covered include:

New or replacement boilers (condensing and biomass)
Insulation (solid wall, cavity wall, loft and floor)
Heating, hot water and lighting controls
Ground and air-source heat pumps
Fan-assisted storage heaters
Flue gas recovery
Draught proofing
Innovative hot water systems

The loan is attached to the property and so passes to a new owner if a house is sold. The National Audit Office was scathing of the original Green Deal’s performance, with minimal CO2 savings created and the loans not considered attractive by customers. If you’d like to find out more about the Green Deal schemes old and new, there’s an excellent page about it on the Which website, link in the shownotes.

From April this year, landlords now have to pay towards proposed works, with the ceiling increasing as described just now.


A tenant has to provide comprehensive information about the works they wish to carry out, including a detailed funding proposal and evidence that installers meet the required standards. A landlord can propose a counter-offer delivering equivalent energy bill savings. As you would expect, the conditions, requirements and exemptions are complex and if you are considering putting in a request you’ll have to do your homework.


If you are a landlord you might be interested in attending one of the workshops or webinars the government is running to consult on this issue. Full details are on the website, but sessions still to come are:

Oxford – Thursday 27 June, 10am to 1pm
Peterborough – Tuesday 2 July, 10.30am to 1pm
Greater Manchester – Wednesday 10 July, 1pm to 3.30pm

If you can’t attend a workshop, there is a webinar on 11 July, 10.30am to 12.00 (noon).


Additionally, the Department for Business, Energy and Industrial Strategy has produced a PDF titled THE DOMESTIC PRIVATE RENTED PROPERTY MINIMUM STANDARD Guidance for landlords and Local Authorities on the minimum level of energy efficiency required to let domestic property under the Energy Efficiency (Private Rented Property) (England and Wales) Regulations 2015, as amended.

The document describes itself as providing guidance to landlords of domestic properties and others with an interest in – quite – “the minimum level of energy efficiency required to let domestic private property” – nothing like aiming for the minimum standard.

Benefit of energy efficiency works

The PDF’s introduction points out the unnecessary energy costs and poor health outcomes (and associated NHS costs, of course) of living in poorly insulated and heated homes, as well as the environmental impact. The report points out the benefit to housing fabric of good maintenance and proper heating. It expresses the wider hope that demand for energy efficiency measures will support jobs and the growth of the green construction industry and supply chain, increasing competition and bringing down costs for everyone.

According to the report many of the most poorly-performing homes were built pre-1919, which ties in with last week’s feature on Energy Efficiency in Historic Buildings. It makes some impressive claims for bringing down fuel bills, as follows:

“Average Annual Cost of Energy >> Data shows that in the PRS, the average modelled annual cost of energy for an EPC band G property is £3,105, and £2,124 for an EPC F rated property. This contrasts with an average annual cost of £1,425 for an EPC band E property6. Therefore, a tenant whose home is improved from EPC band F to EPC band E could expect to see their energy costs reduced by £700 a year so long as there were no wider changes in how they use energy in the property.” That’s quite some saving. To quote further from the PDF:

“Around a third of all fuel-poor households in England live in the PRS, despite the sector accounting for only around a fifth of all households in England.Amongst EPC F and G rated properties in the sector, recent data shows that over 40% of households are classified as fuel poor. Put simply, the PRS has a disproportionate share of the UK’s least energy-efficient properties and fuel-poor households. Installation of energy efficiency measures can help address this.”

District Heating

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A district heating plant

Over the next few weeks we’re going to be looking at the energy efficiency of different types of heating. This week we start with district heating. What is district heating? You might well ask as it’s not common in the UK, providing only about 2% of heat demand, but is well-established in Europe.

Also known as a heat network, it works like this: heat is generated centrally and distributed through insulated pipes to homes and business for heating spaces and water. Heat is generated in a number of ways including fossil fuels and renewables. It can also take in waste heat from nuclear power generation and other sources. Heat networks allow for energy storage on a large scale, making the National Grid’s balancing act that bit easier. There are currently about 50 schemes in the UK using thermal storage, with heat networks as a whole here reducing carbon emissions by up to a ton of CO2 per year with potential for far higher savings.


According to Wikipedia, district heating is more efficient and generates less pollution than individual building-based boilers. There are a number of systems in use, from fifth generation systems that don’t combust on site but use heat transfer, to fossil-fuelled combined heat and power (CHP), with various permutations in operation, making the most of different energy flows as they are available.

According to a January 2018 report by the Association for Decentralised Energy,

“The Government has identified heat networks as a key technology to decarbonise heat and has allocated £320m of funding out [sic] to 2021 to grow the heat networks market. This funding is expected to draw in up to £2 billion of additional capital investment and lead to the construction of hundreds of heat networks in England and Wales. Scotland has set an ambitious target to connect 40,000 homes to heat networks by 2020, representing 1.5TWh (teraWatt) of Scotland’s heat demand.”

Considering the difficulties we will all have in reaching net zero, district networks deserve a closer look.

Heat networks can be retrofitted or connected as a building goes up, with great CO2 savings possible in the retrofit according to the Joseph Rowntree Foundation, which suggests carbon savings of over 40% per home. The government’s own research suggests that heat networks could meet up to 20% of UK heat demand in 10 years from now, and getting on for half by 2050.

Heat networks in the UK

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Buildings in the Dalmarnock Athlete’s Village

So where are heat networks in use in the UK? One supports the Commonwealth Games Village in Glasgow. Situated in Dalmarnock in the east end of Glasgow, this has been described as one of the most significant regeneration schemes in the UK.

After the 88 acre site’s use as the Athlete’s Village for the Commonwealth Games, a site which was itself initially a contaminated brownfield site which had to be treated, it was converted into a 700 home development It includes a sizeable chunk of social housing managed by Glasgow Housing Association (GHA), West of Scotland and Thenue Housing Association. It is now an eco-friendly village with a variety of housing types. The homes are by the river and surrounded by green spaces and excellent recreational facilities as a legacy of the Games.

All the homes and the sports arenas are powered by district heating. It supplies instant heat and continuous hot water. The system is up to 40% more efficient than conventional heating schemes, delivering cost benefits to residents. Together with a Fabric First approach and installation of solar PV panels, there was a 95% carbon reduction on 2007 levels. The construction of this scheme won 25 industry awards.

Heat Network Development Unit

Other schemes and projects continue to connect consumers to heat networks, including more major cities such as Leeds and Bristol. Figures from 2017 show 17000 heat networks supplying about half a million consumers in the UK, up from 2000 networks supplying just over 200,000 users in 2013.

The government runs a Heat Network Development Unit which is seeking investment for over 80 projects. Clearly there is huge scope for growing the proportion of homes heated through heat networks by renewable sources as a plank of meeting net zero. Currently gas features prominently as a source of distributed heat. Heat networks currently in the planning expect to use so-called efficient gas combined heat and power, but also heat pumps and more waste energy.

At the moment the vast majority of customers are domestic, followed by commercial and retail, with a much smaller number of connections to universities, hospitals, public buildings and light industry.

Low awareness

Research carried out by the government three years ago indicated a low awareness of heat networks among British consumers but a fairly positive attitude towards it. Half of respondents are happy to join a scheme if their bills don’t go up. Customers on a heat network show similar levels of happiness with their service as other power customers. Technical reliability is good but there is a lower level of control for heat network customers. A proportion of consumers in older buildings suffer from over-heating because they couldn’t control their heating. Residents of much newer homes complain that poor ventilation leads to over-heating. This is probably worth putting up with though as heat network customers pay about £100 less per annum on their bill than customers with an indvidial gas boiler.

Overall heat network customers are happy and pay lower bills. Is district heating the future for low carbon, energy efficient heat provision?

Energy saving product of the week

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Hippo home pack

This week’s product won’t directly reduce energy use for most people, but still saves a very important resource: water. It’s easy to relax about saving water when we’ve had such a wet spell as just lately in the UK, but it remains vital to conserve water wherever possible.

Toilet bricks

We’re talking this week about toilet cistern water displacement bags, or as you might have heard of them, toilet bricks. They take several forms, but whether bag, brick or blob, they sit in your cistern, meaning that less water is required to fill the cistern after each flush. If an average house has two or three loos it’s easy and cheap to put one in each cistern – it’s another of our favourite fit-and-forget devices, just like our products.

Toilet bricks are often given away free at shows and talks, but with care, a house brick or a small plastic tub with a lid, weighted down, would work just as well. If you do need to buy one, among others available is The Hippo, at £1.49. That’s available from the website Fit, forget, start saving water straight away.

Richard’s energy saving tip of the week

We all know that light colours reflect heat and dark colours absorb it. You can apply this to your home decor to make the most of the money you spend on heating. Most rooms have a light-coloured ceiling – a dark one would feel quite imposing – and this light colour reflects warmth. If your carpet is a dark colour, it will absorb heat and radiate it upwards. This way you keep a warm zone of radiated and reflected heat in your room.

What are we up to? This week we’re making our next batch of Petflaps including several special orders with extended trunking. We’re also preparing for a photoshoot, demonstrating the Petflap fitted into different materials. This photoshoot is long overdue and we look forward to sharing the results with you in due course.

Thank you for listening to episode 4 of the Energy Efficiency Podcast, now available through Apple Podcasts. Until next time you can find us on both Twitter and Instagram as @Ecoflap, and on Twitter we also tweet under @The Petflap

In next week’s episode we’ll look at where to start with draughtproofing your home, wave and tidal energy, and energy efficiency in self build. We’re predicted a heatwave, so remember last week’s tip about keeping fresh air flowing through your home. Bye.

“Werq” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

Energy Efficiency in Historic Buildings: The energy Efficiency Podcast – episode 3

Energy efficiency in historic buildings

Welcome to Energy efficiency in historic buildings: The Energy Efficiency Podcast, episode 3, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.

This week: energy efficiency works to historic buildings, energy efficiency across the world and sustainability in the construction industry.

Net zero carbon emissions

Before we get on with our advertised features, this week Theresa May, outgoing British PM, has put into law what is seen as her legacy: a commitment that Britain will achieve net zero carbon emissions by 2050, which would make Britain the first major economy to enact such legislation. Small countries including Finland and Norway are aiming for earlier dates – 2035 and 2030 respectively. What does May’s move mean for the UK, how likely is it to be  achieved, and how is it likely to be achieved?

Although the move is broadly welcomed, Greenpeace was critical of the carbon credits element of the proposed legislation, which is in the form of an amendment to the Climate Change Act. As a statutory instrument it doesn’t go to a vote of MPs. This is significant because among other criticisms the chancellor Philip Hammond claimed the move would cost £1tn and would lead to spending cuts.


The 2050 date was the recommendation of the official UK Committee on Climate Change (CCC), but May’s proposed use of carbon credits goes directly against the advice of CCC chairman John Gummer. What are carbon credits? According to Investopedia:

“A carbon credit is fundamentally a permit—issued by a government or other regulatory body—that allows its holder to burn a specified amount of hydrocarbon fuel over a specified period. Each carbon credit is valued against one ton of hydrocarbon fuel. Companies or nations are allotted a certain number of credits and may trade them to help balance total worldwide emissions. “Since carbon dioxide is the principal greenhouse gas,” the United Nations notes, “people speak simply of trading in carbon.”

Carbon trading

It’s felt by many that carbon trading places pressure on developing nations. Doug Parr, chief scientist for Greenpeace UK, describes carbon offsetting as “shifting the burden to developing countries” and goes on to describe it as having a history of failure.

Just as the renewables industry we talking about in episode 1, which will be a major plank of net zero, achieving this target requires the correct investment and infrastructure. An article in the Independent suggests that meeting the target will mean

“an end to heating of homes with traditional gas boilers, more green electricity, and a switch from petrol and diesel cars to electric vehicles, walking and cycling.”

With the exception of mothballing gas boilers, none of these are revolutionary moves but none the less May has firmly parked responsibility for the detail as something to be dealt with by future governments, criticised by some as lack of a detailed plan. Whatever your politics, it seems reasonable to allow for accommodating developments in technology. We struggle to predict economic conditions five years ahead at the moment, so to put together a detailed plan to achieve a target that is 30 years away would seem a grand waste of time for all involved. It’s expected the move will receive broad parliamentary support, so we’ll report back on what happened next.

Energy efficiency in historic buildings

energy efficiency in historic buildings
Pre-1919 houses

Energy efficiency in historic buildings is far from straightforward. Historic buildings, from medieval castles to interwar housing blocks, have a tendency to look pretty (yes, even interwar housing blocks have their fans) but be hard work to live in. They can be dark, draughty, very high-ceilinged and so hard to heat, leaky, and hard to update without upsetting what is sometimes fragile or unpredictable infrastructure.

Setting out on a relatively small project such as replacing a bathroom, stripping a floor or fixing a roof can reveal layer upon layer, even century upon century, of fixes, bodged jobs and worn out materials. Improving energy efficiency in historic buildings needs to be approached with extreme caution, an open-mind and ideally bottomless pockets.


Any older building will have been constructed at a time of different priorities, technologies and materials. For instance, early C20th housing was built when coal was an abundant and fairly cheap heating material that no-one though twice about using. The Clean Air Act was a long way off.

This means walls were barely insulated if at all, making those early C20th homes – still routinely in occupation – hard to heat. They are woefully lacking in insulation by modern standards. Wooden window frames, a feature of the vast majority of older housing, have a tendency to rot, shrink and swell. In some houses roofing timbers and floorboards will have warped over time, making it very difficult to achieve a draughtproof fit for windows and doors. Floors often have noticeable gaps between the boards which allow draughts to whistle up if not filled in.

Modern standards

Once upon a time this was considered inevitable, but in the C21st we can go a long way to removing these discomforts. The art is in ensuring houses are brought up to modern standards of comfort while understanding and respecting the building. We don’t want to interfere with its ability to keep standing happily for decades or centuries to come. In other words, approach wrongly, energy efficiency in historic buildings can cause more harm than good.

Listed buildings

When considering works to an older house, first consider whether the house is listed. A listed building comes with a set of criteria unique to that building. As well as three grades of listing, each listed building has its own assessment and features of note. Before doing much more than banging a nail into a wall, it’s important to know the details of your building’s listing entry. You need to understand what it means for the works you propose. If you suspect or know listed building consent is required, this is something you must seek before starting works. A huge amount of information is available online from heritage organisations, government and industry bodies.

Historic England has produced a PDF booklet Energy Efficiency and Historic Buildings How to Improve Energy Efficiency which does exactly what it says on the tin. It includes useful diagrams and graphics, some including charming little characters in historic dress just to make the point. I could quote the whole thing here as it’s fascinating. Here is a brief quote which sets out why it’s so important to understand what you’re dealing with when planning to improve energy efficiency in historic buildings:

“Getting the balance right (and avoiding unintended consequences) is best done with a holistic approach that uses an understanding of a building, its context, its significance, and all the factors affecting energy use as the starting point for devising an energy-efficiency strategy. This ‘whole building approach’ ensures that energy-efficiency measures are suitable, robust, well integrated, properly coordinated and sustainable.”


The pitfalls of work to upgrade energy efficiency in historic buildings are easy to fall into. My background is in historic buildings preservation and I hear a fair bit about various projects. Recently I heard about a well-meant draughtproofing scheme to a listed late Georgian house (that’s the 1820s). It involved sealing around the edges of windows with foam, with no understanding of how air movement worked in that room. Within a short time condensation was forming and the room was becoming unpleasant to be in. Draughty windows can make a room uncomfortable too, but in this instance the work needed to be done against a backdrop of understanding airflow in the room and ensuring a healthy flow was maintained.

To quote Historic England again:

“traditional forms of building construction take up moisture from their surroundings and release it according to environmental conditions. Buildings of traditional construction also tend to have greater thermal inertia than their modern counterparts – they heat up and cool down more slowly. This ability to ‘buffer’ moisture and heat helps to even out fluctuations in humidity and temperature.”

In another instance a building of a similar age had an insulating cladding applied to the entire exterior. Apart from its clanging appearance, the brick and stone underneath could no longer breathe and mould began to appear on the walls. There was no option to remove the cladding, and as this was done to a privately rented house the occupants just have to wipe the mould away every so often. The aim of this work was to improve warmth retention in a hard-to-heat house, but it has had little effect. This is the same situation again – well-intentioned works carried out in the absence of an understanding of how a building’s fabric behaves. We’ll look in a future episode at the rights tenants have to request energy efficiency measures be implemented on their homes.

The Historic England PDF makes the very good point that building owners and occupiers should be involved in planning work to improve energy efficiency in historic buildings. Human beings are creatures of habit, so if works involve change to service delivery within a building – a different heating system for example – the people occupying the building have to understand what they might need to do differently. Although not a historic building, we did hear about a hi-tech building in Westminster that was designed to be very low-energy through the use of clever systems. Unfortunately no-one involved the building’s caretaker, who continued among other things to leave windows open as he always had, thereby defeating much of the energy saving intention.


So what type of work is typically carried out to improve the energy efficiency of a historic building? Historic England makes the fair point that just as in any building, equipment and habit changes can improve matters before the fabric of the building has been touched. A 200 year old building doesn’t need antiquated appliances unless it’s a National Trust kitchen. Pretty much all the usual energy efficiency habits apply just as well in an older building.

Beyond that, the main areas to consider for assessment and improvement are building design and alterations (and understand how it was originally meant to be heated, cooled and used), building fabric, heating, cooling, ventilation, lighting, hot water and appliances.

Low-energy measures

HE advises, very sensibly, starting with low-energy measures to remove sources of discomfort: draughtproofing in a way that works with the flow of air in the building, using curtains in front of doors to block draughts, putting rugs over draughty floorboards. Apply suitably ventilated loft insulation, make any necessary repairs to walls and rooves to avoid unwanted air and water ingress, fit curtains and/or shutters to all windows (this helps to block overheating in the summer too).

In its amber category – involves some risk and/or cost and may not be suitable for all buildings – HE includes:

fitting panelling, secondary glazing, carpets and awnings
reinstatement of a ceiling that has been removed at some point
more involved work to insulate pitched and flat rooves
reinstating or mending rendering and plasterwork, critically using only permeable materials

HE’s red category is for high risk and/or high cost options. These include complex roof-insulating measures, internal and external wall insulation including cavity walls and timber-framed construction, works to floors and the controversial window and glass replacement option.

Windows are a controversial element of improving energy efficiency in historic buildings. Traditional glass does much to bring together the aesthetic of a building. A historic building with modern metal-framed units is visually grating, but of course a lot more comfortable for the occupants than draughty single-glazing in rotting timber frames. HE makes the point that early glass is a heritage asset to be retained. This is always going to be a tricky area.

Case studies

The PDF ends with a set of resources for advice including a link to the energy efficiency area of its website and links to numerous specialist publications with titles such as:

Research into the thermal performance of traditional brick walls
The engine house, swindon, wiltshire: thermal performance of energy efficiency improvements to timber windows
a bristolian’s guide to solid wall insulation

Our favourite Energy Saving Trust has also produced guidance in this area. It’s issued a PDF of case studies of works to improve or in some cases introduce energy efficiency in historic buildings. They include Mill Farm at Assington in Suffolk, a grade II listed farmhouse. The introduction to this case study makes the vital point:

“Modern construction is designed to keep moisture out completely. Old buildings deal with moisture in a different way: historic construction methods allow a certain amount of moisture in, but the permeability and porosity of the materials (see above) allow moisture to evaporate without damage.”

This timber-framed and rendered farmhouse underwent extensive renovation work including renewing and increasing the thickness of thatch, fitting sheep’s wool insulation to walls and replacing a damp concrete floor with breathable lime concrete with clay granules. Additional work was carried out to farmyard buildings focussing on insulation, traditional materials and methods, and features such as a composting toilet.

In all, six case studies are included in the PDF, covering a range of types and ages of buildings, a variety of UK locations and all sorts of considerations. There will be a link to this PDF in the show notes, and whether you’re considering works or not, it makes a fascinating read.

Energy efficiency Worldwide

What’s happening globally to encourage and facilitate energy efficiency? This is a hot topic – literally. According to the International Energy Agency – the IEA – global energy demand rose by 1.9% in 2017 – the fastest annual increase since 2010. This economy-led demand outpaced energy efficiency improvements.

So what’s going on to improve the situation? There’s obviously no simple or short answer to that. The issue is many-faceted, has cultural obstacles, is affected by vast disparities in GDP and has to be a priority for any given administration. What we’ll do here is present a few good news stories.

energy efficiency in historic buildings
A solar array in the USA

There are renewable energy initiatives from private firms worldwide, from the mini grid systems popping up in Africa to plans in Sicily and Sardinia for plants turning solar power into both electricity and thermal energy. Energy efficiency measures at national level will be driven by governments around the world. The trick in the developing world in particular is achieving this without negatively affecting economic growth. In more developed industrial nations, for instance Germany, energy efficiency in energy-intensive sectors can deliver cost advantages.

Data centres

Data centres are particular energy offenders. Ranks of servers generate a lot of heat. It needs to be continually whisked away so that the units don’t overheat. Finding a way to keep this at optimum while minimising energy use is a challenge that has been met by the Telia Helsinki Data Center in Finland. It has been awarded the LEED – Leadership in Energy and Environmental Design – environmental gold rating, and has the highest environmental score of all LEED-certified data centres.

Telia’s award came from its particular focus on energy efficiency and water savings. Rainwater is collected and used as rinsing water, significantly reducing water consumption. The data centre uses renewable energy, and then heats up to 20,000 homes with the heat it produces.

Staying in Finland, a data centre owned by Russian internet giant Yandex, located in Mantsala in Finland, is using the heat it generates to heat the district’s water. The data centre’s manager Ari Kurvi comments that “there’s a very solid business case behind it,”, which is essential for these moves to be adopted and maintained. Using this heat, Mantsala has reduced heating costs and reduced emissions by an impressive 40%. As a whole, the data centre reuses 31% of the energy it draws, with a next phase ready to implement which will increase that reuse to 60%.


It’s great to see that not only are companies adopting energy efficiency measures but they’re reviewing how to improve them and increase that efficiency. In this situation, a saving for Yandex is a benefit for Mantsala, which will bolster good relations between the data centre and its neighbours. A sector which is projected to consume up to 1/5 of global electricity by 2025 needs all the good PR it can get.

Food production

Food production is another energy-intensive area and very much under the spotlight at the moment. Every country in the world is forced to reconsider how it will feed its population at an affordable price without obliterating wildlife and polluting the environment. Studies on OECD countries suggest that the food system accounts for 20% of total energy use in some. This covers activies from farming to producing processed foods, and includes wastage. An OECD publication from the Joint Working Party on Agriculture and the Environment, titled IMPROVING ENERGY EFFICIENCY IN THE AGRO-FOOD CHAIN, highlights that there are numerous areas for improving energy efficiency but that identifying these requires further research.

US farms

An article on the US website Farm Energy states that “U.S. farms have almost doubled their average energy efficiency over the past 25 years” but that there are still many opportunities to improve this. This includes simple and obvious actions applicable worldwide such as maintaining equipment so that it works at optimum efficiency, through investing in more energy efficient equipment, improving building standards and using nutrient supplements for livestock more efficiently.

In December 2018, funding for a renewable energy program was included in the Farm Bill that was signed into US law. The Department of Agriculture’s renewable energy grant and loan programs are pulled together under an initiative called REAP for Rural Energy for America Program. It makes sense to bundle renewable energy legislation with bills relating to agriculture as agriculture is so energy intensive. When Barack Obama was in office REAP laid the groundwork for dealing with the carbon footprint of US agriculture as well as promoting rural economic development by supporting clean power projects, including solar-powered grain dryers.

The Americal legislators view this new move as being as much about America’s energy independence as anything else, and using less energy clearly helps here. Power generation projects eligible for REAP funding include biomass heating, geothermal, lower wattage hydropower, hydrogen and wind and solar generation. Energy efficiency upgrades include energy efficient HVAC systems, insulation, lighting, refrigeration, pumps for sprinklers, switching from diesel to electric irrigation motors and crucially replacing energy-inefficient equipment.

Iowa in particular looks to have benefitted from REAP funding. Grants and loans were used to fund solar arrays, refrigeration units and low-energy lighting. Lighting comes up again and again as a huge drain on power.

Food waste

Pleasingly, the USDA funds research aimed at cutting costs and improving energy efficiency, not just capital projects. As well as research into biofuels – not an uncontroversial topic – it’s also tackling food waste. Wasted food wastes every iota of energy and work that has gone into producing it.

Currently the USDA and California Department of Agriculture are funding a project to dry the nutrient-rich waste from fruit and veg processing – skins, seeds, stems and so on. Being wet it doesn’t have a long life and though some of it can be used, most ends up in landfill. The crunch is to find an economical way of drying this matter, known as pomace, without using fossil fuels. The aim is to use 100% solar power and experiments using it to dry tomato and prune pomace are going well. Companies are interested in getting involved. Ultimately, improving energy efficiency in food production is going to be achieved through combining these quite focussed projects with broad energy efficiency measures focussing on infrastructure.


Japan is in the contradictory position of being one of the highest importers of fossil fuels in the world but one of the most advanced in renewable energy research. Japan has a 94% reliance on imported fuels and is always in the top few countries for quantities of gas, coal and oil imports. Its island nature in the Pacific Ring of Fire puts it in a unique position for such a developed economy and has made it the world’s third biggest power producer with huge per capita power consumption. In 2016 82% of power was generated by conventional fossil fuel-based methods, albeit its coal plants are considered to be the most efficient in the world.

Since the earthquake and tsunami in 2011 this profile has been compounded by altered attitudes to nuclear power, including a complete switch off of its nuclear generators (some since re-opened). It has increased Japan’s need to find new sources of energy. To meet its pledge as a signatory of the Paris Agreement, it needs to reduce greenhouse emissions by a quarter by 2030, and increase the share of renewable energy in the mix to about the same. However, Japan also plans to build more coal-fired plants, so what exactly is going on?

According to polls, climate change is taken seriously by about half of the Japanese population, but the country is coming in for severe criticism over its plans for coal burning plants. Its own foreign ministry’s official advisory panel on climate change has pointed out that failing to move towards decarbonisation could see Japan being left behind economically. Even its own targets are well below other developed countries. However, it is implementing energy efficiency measures and it shoiuld be noted that Japan’s population is falling. This means fewer people to consume power, but also that per capita emission statistics won’t look good.


Despite its vulnerability to earthquakes, Japan has included a 20% share of nuclear energy in its most recent basic energy plan and views it as an important electricity source. Together with its plan for renewables, it makes a 44% zero-emission electricity share and refers to renewables as “major electrcity sources”. It’s less than many people wanted but it is progress of sorts.

energy efficiency in hisstoric buildings

So what is happening to promote energy efficiency in Japan? There are plans to have 40,000 hydrogen vehicles on the road by 2020. It has promoted the use of electric cars through subsidies. There are big plans to improve the energy efficiency of buildings through a complete switch to LED lighting and installation of fuel cells in homes, with electric or fuel cell vehicles making up at least half of all new sales in about ten years from now.

Japan has a law on the “rational use of energy”, brought in in 1979 in response to the oil crisis. In aims to promote energy efficiency across the board, including in transport and industry. There are now mandatory regulations on energy efficiency standards in large buildings, together with ambitious plans to reduce energy consumotion of new homes and buildings to zero in the next decade.

Thanks to Jocelyn Timperley’s article at for the background to this feature.

Sustainability in the construction industry

If a building is standing but is not energy efficient, what is the most energy efficient approach? Is it to acknowledge the materials and energy that have gone into building it and leave it be? To do what works you can? Or to raze it and start again? Sometimes the answer’s obvious, sometimes it’s not, but it can be helped along by considering the sustainability of any proposed works.

Looking at a building as if it was made of Lego, could these bricks be reused? Just because they have been used in an energy-inefficient configuration in one building doesn’t mean they can’t be re-used in a different and much more energy efficient building. Even using them in a regular building reuses the energy and work that has gone into making them. Roof tiles, timbers, steel joists and all sorts of other elements of a building can be re-used. It takes commitment and planning on the part of the developer but it brings rewards.

Glasgow Queen Street station

energy efficiency in historic buildings
Glasgow Queen Street undergoing refurbishment and extension

Glasgow Queen Street station, first opened in 1842, has been undergoing redevelopment for a wee while, extending platforms, providing fully accessible entrances, expanding the concourse and providing new facilities. It’s easy to imagine this will see innumerable skips filled with smashed up materials ready for dumping, and the previous modernisation in the late 60s/early 70s saw just this, together with demolition of Victorian station buildings. Much was to change in Glasgow’s attitude to its built heritage but we mustn’t get carried away on that just now.

Curiously, NetworkRail’s web page on the work doesn’t mention the recycling and reuse that is going on. You have to look quite hard to find the details. There is a Twitter account dedicated to covering the work, @NetworkRailGQS, which feeds us bits and pieces of information. On June 5th this year they tweeted under the hashtag #WorldEnvironmentDay:

“In total, 14,000tn of redundant material from #GQS has been reused by a range of sectors including housing and road projects, as well as the bio-mass industry.” and “Some of the concrete removed was also crushed into small stone and then re-used as part of the base layer for the new station”.

According to their Twitter feed “More than 95% of demolition material has been recycled and 100% of the brick, timber & concrete removed from site re-used elsewhere in the construction industry” – 100%! This project could stand as an example of what can be achieved. These impressive figures were covered in an article in Scottish Nationalist paper The National earlier this month, where it was pointed out that:

“The team also significantly reduced the carbon footprint of the demolition works by carrying out the recycling work within Glasgow.” and the only materials not recycled were hazardous ones such as asbestos. Achieving this within the constraints of working in a city centre location is an achieved to be proud of.

Alstom, Birmingham

At another rail site, the former home of train maker Alstom in Birmingham, 11 hectares is being cleared as part of HS2. Setting aside the merits or otherwise of demolishing a piece of the UK’s railway history, 413,000 tonnes of material has been created during the demolition. Contractors plan to reuse most of it on site.

This is major sorting job, which is carried out on site, splitting out plastic, glass, cement, timber, and insulation materials. Aggregate is crushed and left on-site for road and grounds use. Plywood has been put to a range of imaginative uses including foot scrpaers, planters and clipboards and well as temporary fencing and lockers. Reusing reclaimed materials for temporary structures makes particular sense. An article on website goes into detail about all the considerations of this type of work, including managing heavy plant over subterranean voids, hazardous materials and the different methodologies required. To date, 8000 tonnes of brick have been extracted as well as 4000 tonnes of metal and 1 1/2 of timber.

Circular economy

Despite the good work at Glasgow Queen Street, construction is the largest consumer of natural resources in Scotland and the biggest contributor of waste going to landfill. A new partnership between Zero Waste Scotland and Construction Scotland Innovation Centre is on a mission to demonstrate to the construction industry that a ‘circular economy’ approach where nothing is wasted can offer commercial advantages. The partnership is putting on a programme of events, including:

a series of joint events to promote innovative ‘reuse, recycling and circular thinking’ initiatives within construction;
issuing ‘innovation calls’ to generate innovation projects around waste reduction and reuse themes;
collaborating on further sector-wide strategic projects.


In Hong Kong the focus is on materials ancillary to construction, in this case bamboo scaffolding. It’s a common sight in Hong Kong and tends to end up in landfill after use. This year a scheme has been started to upcycle this bamboo. It can be made into furniture and outdoor toys, and workshops run by HK group Green Come True have been showing people how to make small items from the scaffolding, including wind chimes and pen holders. This is intended to protray the upcycling process as fun. Local designers and architects have been invited to use the bamboo creatively and the plan is to continue collecting the bamboo and widening participation in reuse.

There are many such small projects around the world, including a company in Vancouver that ‘deconstructs’ houses and reuses the wood in renovations. Between demand from the bottom up, and legislation and initiatives from the top down, progress is being made, even if it’s a bit lumpy and quite variable across the world

Energy saving product of the week

One example of an LED light bulb. Image credit:

This week’s energy saving product is something that is rapidly gaining ground in both industry and domestic use: LED lighting. Named for their component light emitting diodes, LED bulbs far outlive incandescent bulbs and are more efficient than fluorescent lighting. Wikipedia puts an LED’s energy use at 10% that of a traditional incandescent lightbulb.

According to 20% of the world’s energy use goes into lighting so LEDs are a great energy efficient alternative. They contain no mercury so are less difficult to dispose of. Together with their longer life span they are a more environmentally friendly and energy efficient solution than many forms of lighting.

LED bulbs come in all shapes, sizes and wattages. Some lighting comes fitted with sockets that take only LEDs, but it’s easy to find LEDs with standard bayonet or screw fittings for your existing lamps and light fittings.

We don’t have one specific make of LED to recommend as they are widely available in the shops and online. Next time you need to replace a bulb, look for an LED alternative.

Richard’s tip of the week

This week’s tip is about keeping a cool airflow through your house in warm weather – if we get any. Open a downstairs window on the shaded side of your house and an upstairs window on the sunny side, and fresh air will naturally and continually be drawn in from downstairs to travel up through the house and out through the upstairs window. If you have a vent in a downstairs wall the same thing will happen, if the vent is open. This can help to keep a house cool in warm weather. Fingers crossed.

What are we up to? We’re refining our trunking manufacturing and waiting for delivery of our next lot of raw materials. We have several orders with extended trunking to make up in this next batch. If you need a Petflap with longer than usual trunking get in touch with us and we will sort that out for you. Currently we can provide trunking suitable for walls about 60cm thick.

Thank you for listening to another episode of the Energy Efficiency podcast. We will be available through Apple Podcasts very soon. Next week we’ll be looking at the energy efficiency of different types of heating, looking at net zero, and tenants’ rights around energy efficiency works to private rented homes. Please join us then.

“Werq” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

Passivhaus: The Energy Efficiency Podcast – episode 2


Welcome to Passivhaus: The Energy Efficiency Podcast, episode 2, the podcast that brings you a mix of energy efficiency news, products and tips all year round. We’re interested in profiling people and products involved in promoting energy efficiency habits, products and information, so please do get in touch if you have something to contribute.


A passivhaus in Darmstadt

If you’re interested in energy efficiency chances are you’ve heard of passivhaus. In very simple terms passivhaus is an airtightness standard achieved through high-performance windows, doors and other danger zones together with very high levels of insulation and efficient heating systems. The certification can be applied to whole buildings, specific components such as windows, and the architects and tradespeople involved in the design and build. Rigorous testing is carried out before anything or anyone involved can be designated to have met the required standard.

As a guide, a passivhaus building will have excellent insulation, low-energy services and require very low levels of energy to keep at a comfortable temperature. In the UK building regulations typically require a level of insulation and energy efficiency far lower than passivhaus, and within that standards vary across England, Scotland and Wales, and differ between domestic and non-domestic buildings.


However some organisations in the UK are building to passivhaus standards. They clearly recognise the benefits of keeping buildings at a comfortable draught-free temperature at a low energy cost. Exeter City Council is one. For the last 10 years all new council buildings in Exter, both residential and commercial, are very low energy (meeting passivhaus standard), healthy (meeting the German Building Biology principles), climate ready and set within a sustainable landscape. The Association for Public Service Excellence has this to say:

“These buildings are healthy for residents and occupants, comfortable regardless of the weather and extremely cost effective to run (thereby helping to eradicate fuel poverty). From a Council perspective we have reduced operating and lifecycle building costs, happier and healthier tenants with reduced rent arrears and anti-social behaviour and exemplar buildings that are performing way beyond comparable building regulation compliant assets.”

But what do you have to do to create buildings operating to such high energy efficiency standards? It comes down to reducing heat loss, maximising the effect of passive sources of heating such as sun, body warmth and extracted or emitted heat from household appliances, and making up any shortfall with low energy heating systems. The Passivhaus Institute describes it as

“A Passivhaus is a building in which thermal comfort can be achieved solely by post-heating or post-cooling the fresh air flow required for a good indoor air quality, without the need for additional recirculation of air.”

High standards

This can be a very complex process requiring expensive high-performance elements such as triple-glazed windows and a mechanical ventilation system with efficient heat recovery; extremely detailed planning; and specialist builders and fitters.

It’s not feasible in many cases of renovating an existing property, in which case EnerPHit can be a more appropriate standard to aspire to. This is a slightly less exacting standard designed for renovations, particularly where the architecture of the building needs to be conserved. Improving the energy efficiency of historic buildings without causing more problems than you solve is something we will look at in a future episode.


A Victorian house

The UK has one of the highest proportions of pre-WWII domestic buildings in Europe. Unsurprisingly old and inefficient buildings have been identified as one of the biggest contributors to energy wastage in the EU.

The EU has identified energy efficiency as one of the pillars of its policy response to addressing the challenges of climate change and the reduction of greenhouse gas emissions. There is an EU-funded PDF brochure available titled EuroPHit: Increasing the European Potential, Implementing deep energy step-by-step retrofits. The link will be in the show notes. It discusses passivhaus and the scientifically-quantified benefits of the passivhaus standard.

EnerPHit benefits from the passivhaus expertise that is available in the UK and beyond. While accepting that it’s not possible to reach such high standards, working with passivhaus principles in an EnerPHit project will dramatically improve the energy performance of an older house. The Passivhaus Trust website includes a number of case studies of both social and private housing, commercial buildings and educational settings, which have undergone renovations aimed at achieving EnerPHit standards.

EnerPHit focusses on improving the energy performance of the fabric of a building while accepting that many aspects of a building are fixed: location, orientation and often a thermal bridge or two that just can’t be eradicated. According to the magazine Homebuilding & Renovating:

“To achieve EnerPHit you must achieve:

A space heating and cooling demand of 25kWh/m2/year (compared to the Passivhaus standard of 15kWh/m2/year)
Instead of an airtightness performance of 0.6 air changes per hour you need to achieve 1.0 (the Building Regs for new homes require between 5 and 15 according to the Chartered Institution of Building Services Engineers)”

Deep works

To achieve these sorts of figures, though not as rigorous as passivhaus standards, can still be a huge undertaking. It can involve digging out floors and replacing roofs, all within the confines of an existing build. In this situation even more perhaps than for a new build, an expert and very well-informed design team is crucial. The Homebuilding & Renovating article is very informative, so if you’re considering deep energy efficiency work on an existing build it’s very worth while reading.

Open Days

Every year the UK Passivhaus organisation puts on the UK Passivhaus Open Days, as part of the International Passivhaus Open Days. This year it’s running the weekend of 28th-30th June, and details can be found at

Community Projects

The Petflap on red

Most people won’t undertake a large scale project to build or retrofit a house to passivhaus or EnerPHit standards. Many people will make some changes, install items such as a Chimney Sheep or a Petflap draughtproof pet door, hang a curtain over the front door or maybe replace a boiler.


Many households have neither the budget nor the scope to make any improvements. It’s in this situation that community groups can provide an invaluable service. They offer advice, subsidised services and products, and in some cases obtain grants. Plymouth Energy Community – PEC – is one of these organisations. In 2016 it received £500,000 from the Big Lottery Fund for a four-year project to help disabled people stay warm, well and comfortable in their homes.

The problems most commonly encountered were issues with the building fabric – poor insulation and black mould for example – but also problems paying bills and a lack of understanding of how to get the best deal from an energy supplier. PEC visits people in their homes. It advises on the best energy deal and how to use energy efficiently, and looks at how the household could benefit from grants and schemes such as the Warm Home Discount Scheme.

The Warm Home Discount Scheme

The Warm Home Discount Scheme is a government initiative open to people in receipt of specific pension top-ups, and those on a low income who qualify for their supplier’s criteria for the scheme. There’s potential for up to £140 off an electricity bill that comes in the form of a discount off the bill rather than as a payment.

These and other grants and schemes can be complex to apply for, so the assistance of groups such as PEC is very welcome and makes a real difference to those it reaches. The Royal Borough of Kensington and Chelsea runs a similar scheme under the title Homes4Health, focussing on the poor health outcomes of living in a damp home, such as respiratory and circulatory problems. This free service is delivered by the environmental charity Groundwork London, and aims to reach young families, elderly residents and those with multiple health conditions. The range of services offered by Groundwork London through this scheme is impressive and wide-ranging. It includes practical help such as installing small draughtproofing measures.

There are similar schemes run all over the UK so if you or someone you know could benefit search up something like “warm homes energy efficiency” with your location and see what comes up.

Thermal imaging

The magnificently-named C>H>E>E>S>E project in Bristol is doing something different from many community projects. It conducts thermal imaging of a home from low-cost to no-cost depending on a household’s circumstances. A clear understanding of a building’s thermal performance is essential if works to the home are going to focus in the right and most cost-effective places. CHEESE’s work typically shows up poorly-fitting windows, missing insulation and draughts between floorboards. These can all make a home feel uncomfortable in cool or damp weather.

Generating power

Not all community energy efficiency projects focus on home improvement and help to pay bills. Some schemes actually generate the energy. There’s a list of projects on the Community Energy England website. Back to Plymouth, a solar array has been built on derilict land, providing enough clean energy for 1000 homes. This is an excellent use of derilict or brownfield sites. The project is forecast to provide a community benefit fund of approximately £2,900,000 to support PEC’s grassroots work.

In Talybont on Usk a group is generating hydroelectricity for the community. This first community hydro scheme in Wales runs a 36kW hydro electric turbine off the compensation flow from Talybont Reservoir. Since launching in 2006 the group has diversified into a community eco car share scheme that runs one electric van, and a car running on recycled vegetable oil. The group has also installed PV panels on the community hall roof which helps cover the hall’s running costs and powers the community electric car. The group continues to develop and looks to be a great example of what can be achieved.

A project straddling the two community energy efficiency models is Energise Barnsley, which has installed free solar PV panels on the roofs of over 300 council-owned homes. The majority of these homes are bungalows with elderly residents. A proportion of them are on pre-payment meters. The residents benefit from savings through the use of a solar electricity monitor which indicates when the solar panels are generating and so when they can use free electricity. So far residents have saved over £40,000 and reduced carbon emissions by 400 tonnes. Schools, sheltered housing and community buildings in Barnsley have also had the panels installed. This makes the combined size of the portfolio the largest UK community energy project by the number of roofs installed on.


Reading up on the projects listed, it’s clear that starting up a wind, solar or hydro project is a slow and complex process requiring various funding streams, feasibility studies and often planning permission. Many projects listed are great ideas but are only part- way through this process.

The UK Energy Research Centre – UKERC – website says that although exact numbers aren’t available, it’s estimated there are about 300 small energy generation schemes in the UK. The sector was going at a great pace until recent political changes reduced support for schemes of this sort through changes to the feed in tariffs. This has slowed down development.

However a press release on the UK Power Networks website states that community energy is powering thousands of homes in the South East, East of England and London, according to a newly published report into local generation with Community Energy England and Community Energy South. The majority of community electricity generation in the region comes from two solar farms owned by Orchard Community Energy in Kent and Meadow Blue Energy in West Sussex. They generate 10.4 MW between them. This is very encouraging and we hope to see more good news of this nature.

Smart Meters

Smart meters have for a few years now been hailed as the solution to energy wastage. We must all have seen a friend very excited by the new monitor and turning off appliances they had previously hardly considered. This tends to be a flurry of enthusiasm in the early days, then normal service is resumed. The reality is that smart meters themselves do nothing to reduce a building’s energy usage. They can draw attention to the most energy-hungry items and allow the householder to make a judgment to discard, turn off or upgrade an item but ultimately this human effort is what makes the difference. Smart meters can lull the homeowner into a false sense of security of having ‘done something’, when actually nothing will change without their input.

Changing habits

Depending on what you read, smart meters are a fad, are here to stay, will save half a billion a year or reduce your annual bill by about a tenner. Clearly smart meters divide opinion. According to a Which report on smart meters:

“34% of smart meter owners think their gas and electricity use has reduced since they had a smart meter installed. In contrast, 20% of smart meter owners think theirs has increased.”

The rest don’t think anything’s changed. It seems installing a smart meter is most likely to lead to savings if the homeowner has requested one, ie the individual was already aware of energy efficiency and wanted a tool to help them best achieve it, so the willingness to work with the meter was there in the first place.

Widespread installation

The government would like all homes to have a smart meter installed by 2020. There’s no obligation and anyone has the right to refuse. Seeing smart meters in all homes is part of the process of developing a ‘smart grid’. This smart grid would allow for more efficient matching of supply and demand. Balancing this is a headache for the industry at the moment.

Installing smart meters widely should remove the need for estimated bills and getting into a cobwebby dark and awkward corner with a torch to read the meter. Some energy suppliers offer so-called agile tariffs which display energy prices via the smart meter on an eg half-hourly basis. A householder can then use energy when it’s cheapest. On the other hand, the cost of installing a smart meter in every home adds something to the bill.


Some earlier meters have lost functionality when the householder has switched supplier but this can be fixed by a wireless update. Failing that the energy supplier is required to fit a new meter.

According to the Octopus Energy website:

“As of March 15 2019, SMETS1 meters are no longer Ofgem compliant.”

They go on to explain that there’s only limited SMETS2 stock available in the UK currently. Reading around energy suppliers’ websites, it’s clear that they have reservations and are holding back on full scale installation to monitor smart meter performance and problems.

These problems seem not to be going away any time soon. According to The Independent:

“Energy giant SSE agreed to donate £700,000 to the official fund for supporting vulnerable bill payers this week after failing to meet obligatory smart gas meter installation targets. It’s the latest in a series of hits, delays and, ironically, spiralling bills to have plagued the much-vaunted smart meter rollout, designed to deliver cost-saving technology to 30 million homes and small businesses by 2020.”

The article goes on to quote Smart Energy GB, the agency promoting smart meters. It said that of 2000 people polled more than a third said they would be more likely to buy an electric vehicle (EV) if they could use their smart meter to programme charging for the cheapest periods. EV use could play a key role in promoting enthusiasm for smart meters in the home.

So far the greatest benefit of smart meter roll out is as much for the benefit of the energy suppliers and the national grid as it is for the customer. The ball is in the companies’ court to help householders understand how to get the best from their meters.

Energy saving product of the week

This week’s energy saving product is another simple but effective idea. Radflek Radiator Reflectors are laminated aluminium foil panels that sit against the walls behind your radiators. They reflect back into the room heat that would otherwise be wasted against an external wall. Tests showed that Radflek reduced heat transfer through walls by 45%

Radflek’s website claims that it reflects 95% of wasted heat back into your room, really exceptional performance. We like the idea of these reflectors because they prevent waste, one of our top aims, but like our products they are fit-and-forget solutions. The panel stays in place all year round and whenever your heating comes on it will start doing its job immediately.

At an affordable price of around £20 for six panels, Radflek expects to pay for itself in a year or so. The panels go on for years so you make savings every year. Added to that, Radflek’s site describes the product as visually unobtrusive, easy to fit and requiring no DIY skills. For the final seal of approval, The Energy Saving Trust recommends Radflek Radiator Reflectors.

Richard’s Energy Saving tip of the week

If you want to fit insulation to parts of your house but have only a small budget, not enough to fit out a whole room or house, you will get the maximum effect for your money by insulating the walls from the ceiling down. This prevents the warm air that rises in a room from chilling down as much as it would in a room without insulation at the higher levels. Together with the thermostat ledge tip in last week’s episode, this will help you keep warmer for less outlay and get the best from your thermostat.

Letterplate Eco

What are we up to? We’re still in flux while we work with new kit, and we’re expecting samples to arrive soon from a new manufacturing partner. While keeping a close eye on quality and always looking at ways to make our manufacturing as quick and simple as possible, we are looking to work with partners as much as we can. This is how we will increase manufacturing volume and bring the Letterplate Eco to market as soon as we can.

Thank you for listening. Search for Ecoflap on Twitter and Instagram to keep up with us until next time. Next week we’ll be talking about energy efficiency in historic buildings, energy efficiency across the world and sustainability in the construction industry. We are lining up a couple of interviews for future episodes, and as always we’re keen to hear about energy efficiency initiatives, projects and products, so please do get in touch if you have something to contribute. Until next time.

“Werq” Kevin MacLeod (
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