Millions of homes could be fitted with heat pumps and boilers under Ed Miliband’s bid to decarbonise the UK.
The Energy Secretary’s Department has unveiled plans to set up an “alternative hybrid system”, where families can use a heat pump to heat their homes but keep a small gas boiler to produce hot water.
Officials are investigating the project amid growing concern that many people will never be able to replace their boilers with heat pumps because their homes are too small for the water storage cylinder needed for washing and bathing.
Mr Miliband wants domestic heat pump installations to hit 600,000 by 2028, up from 40 last year.
However, the technology remains too expensive for most households, as a heat pump installation typically costs £14,000. This means that, even with a subsidy of up to £7,500, installing new heat pumps is still more expensive than replacing gas boilers, which usually cost between £2,000 and £4,000.
A new report from the Department of Energy Security and Net Zero said: “Establishing the quality of heat pumps is an important step in creating a strong foundation for the heat pump market.”
Mike Foster, chief executive of the Energy and Utilities Alliance, a trade association for manufacturers of boilers, heat pumps and radiators, said the combined systems would help cut carbon emissions from millions of homes.
He said: “Installing heating pipes in homes can be very disruptive, often involving the installation of cylinders to store the hot water it produces. But 60pc of UK homes don’t have a storage cylinder and lack the space to put one in.
“This means that the central house is to install a hybrid system where the heat pump runs the central heating and the small system provides the hot water.”
Ofgem, the electricity producer, said such mixed schemes could be eligible for tender but only for the heat pump part of the scheme.
Heat pumps are very efficient, often delivering up to four units of heat for each unit of electricity required to run them.
Grants for their installation come from Ofgem’s boiler upgrade scheme, which was introduced in May 2022 as a way to reduce the 68m tonnes of CO2 emitted each year from home heating – almost 18pc of UK emissions.
Most of this output comes from 25m homes fitted with gas-fired boilers and another 2m using oil-fired boilers.
The aim is to eventually transfer boilers to low-carbon heating systems such as air-source or ground-source heat pumps. This works by removing heat from the environment – either the air or the ground, depending on the type of heat pump.
They then use electricity to transfer this heat into people’s homes where it can be used in radiators, floor heating or air conditioning, and provide hot water for taps and showers.
Louise Howlett, of RA Brown Heating, a member of the Heating Trades Network UK, said combined heat pumps could help homes cut emissions and utility costs but came with the difficulty of maintaining two separate appliances.
He said: “For homeowners looking at this option, ensuring proper design and professional calculations of the heat pump’s efficiency is essential,” he said.
A Department for Energy spokesman said: “We are supporting the targeted delivery of combination heating systems in England through the Warm Homes Social Housing Fund and the Warm Homes Local Grant.”
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