"Radiators would have to run 10 degrees cooler under changes to homes needed for Britain to hit net zero, the public has been warned.
The Government has said it wants 600,000 heat pumps replacing gas boilers every year by 2028 to help decarbonise the country’s home heating, which accounts for 10 per cent of the UK’s greenhouse gas emissions.
But MPs and experts have warned that without a massive programme to address the UK’s draughty homes and scale up engineering skills, people could be left in the cold by the technology, which works by drawing in heat from the air or ground outside.
While gas boiler heating systems can pump 60C water into a home’s radiators, the Climate Change Committee, which advises the Government, assumes heat pumps will operate at 50C.
To keep homes warm, that may require bigger radiators, underfloor heating and improved insulation, with full modifications estimated to cost on average £18,000.
Homeowners will currently have to cover the costs themselves as the government scrapped its grants scheme after just six months.
Heat pumps can reach high temperatures, but become inefficient and expensive to run, though a regular hot cycle is necessary to kill legionella, which can lead to Legionnaires Disease.
Darren Jones MP, the chair of the Commons business and energy committee, said: “It’s not the same as gas.
You can’t just knock up the dial on your wall a little bit and suddenly it gets a bit warmer”.
The UK is nearly halfway to meeting its target of reaching net zero emissions by 2050, but the transition has so far been achieved largely by phasing out coal-fired power plants and boosting the offshore wind industry.
The next phase will require individuals to make much more personal changes to the way they travel, heat their homes and what they consume.
That carries risks if people are turned off by the transition.
The Department of Business, Energy and Industrial Strategy (BEIS) established a behaviour change unit last year to tackle how the Government will persuade people to make the necessary transition.
Home heating is considered one of the biggest hurdles, because of the level of investment and intrusion required to change it.
"It is a problem to persuade people that they can’t necessarily rely on a system which will transform the warmth of the room that they’re in, in a matter of minutes,” said Philip Dunne MP, chair of the environment committee.
“And that does require education.
And it’s difficult to do with people who are not committed to the environmental cause.
They’re just concerned that they’re cold."
To keep homes warm, that may require bigger radiators, underfloor heating and improved insulation, with full modifications estimated to cost on average £18,000
Energy efficient homes
It’s not just heat pumps that mean homeowners might need to make costly adjustments to their homes.
The Government wants the majority of homes to be EPC C by 2035, and 2030 in the private sector.
That means retrofitting measures in the two-thirds of homes that are currently EPC D or below.
Measures might include double or triple glazing, solid or cavity wall insulation and underfloor heating.
Energy efficiency could be linked to lower mortgage rates, or higher loans to cover improvement measures.
However, the Government has scrapped its flagship £1.5bn Green Homes Grant scheme, which gave homeowners up to £5,000, or £10,000 for low-income households, toward the cost of insulation and installing low-carbon heating, after just six months.
The government wants heat pumps to replace gas boilers, but they are bigger, noisier and other changes to homes are needed to ensure they don’t leave inhabitants cold.
Experts say heat pumps warm homes to a comfortable level, provided the right system is installed, and can bring benefits by reducing the flow of indoor air pollution by maintaining a lower, constant level of heat.
"[A heat pump] is a low temperature heat system.
It’s an advantage, but can be seen as a disadvantage,” said Nathan Gambling a consultant specialising in training heating engineers.
"Ideally all our heat systems in our home should be low temperature, for a number of reasons.
Low temperature is a healthier form of heating."
But he warned that heating engineers lack the expertise to ensure people have the right system installed when they make the swap.
And information for those wishing to go green in their homes can be hard to come by.
“Right now if you want to switch to a low carbon heating, you’ve got to go on some kind of grand journey of discovery.
You need to become a project manager or a building physicist,” said Mr Newey, who is director of strategy at innovation agency Energy Systems Catapult.
“It’s quite an invasive process in your home,” said Darren Jones MP, the chair of the Commons business and energy committee .
"And because the market is not fully mature yet the cost of installing is very high.
You’re looking at 10 to 15k, plus invasive work in your home.
“Government, energy suppliers – they’re not really talking to customers about this, or explaining that something significant is gonna have to change.”
Heat pumps are also a bigger and noisier option than a gas boiler, which could prove an issue when they’re installed on a large scale.
“Architects historically haven’t given any sort of thought to the heating.
We’re given a kitchen cupboard for your boiler.
So that mindset is going to have to change,” said Mr Gambling, who runs a podcast, BetaTalk, looking at the transition to low carbon heating.
“We haven’t really got to that point in the uptake where we know whether that’s an intrusion on people’s comfort,” he added.
“They’re not as noisy as some people think, but then again, noise is quite subjective.”
... Accommodating electric cars will mean homeowners need a charger and will face increased energy bills.
New petrol and diesel cars will be banned from sale from 2030, and the CCC wants 64 per cent of all cars on the road to be electric by 2032.
Installing a charger at home can cost up to £1,000 to install, with Government grants covering up to £350.
... Electricity bills will increase with daily charging (though still cheaper than fuel costs), making shopping around for the best tariff crucial.
Many supply electricity at significantly cheaper off-peak prices which can be utilised if it has smart features.
Some can even be linked to the renewable energy supply in your home, such as solar panels, and can sell your excess electricity back to the grid.
But with many deals available online, there is a potential for those without digital access to be left behind, warns Dhara Vyas, the head of future energy services at Citizens Advice.
For those without off-street parking, trailing cables across pavements is technically illegal."
