Warmth from the earth and air: could heat pumps replace our gas boilers? | Energy industry
ÖOne of the biggest polluters is a part of everyday life that is easily overlooked: the fossil fuels used in our homes for heating, hot water and cooking account for more than a fifth of the UK’s carbon emissions.
Because of this, the government plans to ban gas boilers in new buildings from 2025, a policy that could be extended to all new gas boilers in homes from the mid-2030s. After that date, newly installed heating systems must be low carbon or convertible to clean burning fuels such as hydrogen.
While government trials with hydrogen continue, electric heat pumps have proven to be an excellent option for individual households.
Put simply, a heat pump behaves like an inverted refrigerator by extracting energy or heat from the outside air, the ground or nearby water and concentrating the heat before it is directed inside.
The government is expected to set out its plans to decarbonise homes in a long-awaited strategy paper this fall, including a replacement for the current Renewable Heating Incentive Scheme (RHI), which will close in March next year.
RHI pays £ 6,000 quarterly over a seven-year period to cover the cost of heat pumps. Ministers are reported to be considering replacing it with a £ 400 million boiler scrapping program that would offer £ 7,000 in grants.
Heat pumps are already popular, but the cost is many times the price of a gas boiler, starting at £ 6,000 for an air pump; a borehole pump could cost as much as £ 10,000. And many houses require extensive insulation work before installation.
“It takes a change in mindset,” says Richard Lowes, heating expert with the Regulatory Assistance Project. Rather than relying on a hefty boost of fossil fuels to heat a cold house quickly, it’s more important that the heat pumps run continuously – albeit at a very low level – to gently bring the heater to an even temperature, he says . “Your refrigerator doesn’t blow cold air all the time,” he says. “But it keeps your food cool by adapting to very slight increases in temperature, and only when necessary.”
At least 36,000 heat pumps were installed in homes and businesses across the UK last year, and installations are expected to nearly double this year to 60,000 to 70,000, according to the Heat Pump Association. They will have to increase tenfold over the next seven years to meet Boris Johnson’s goal of installing 600,000 a year by 2028 last November.
Boris Johnson plans to install 600,000 heat pumps annually by 2028. Photo: Tayfun Salcı / Zuma Press Wire / Rex Shutterstock
The move away from gas heating poses new challenges and opportunities for British energy providers. The heat pump market is currently dominated by a handful of manufacturers – including Mitsubishi, Daikin, Samsung, LG, Vaillant and Calorex – and around 1,000 installers. Ovo Energy and Octopus Energy carry out customer tests before a new start for innovative heating tariffs could emerge in the future.
However, in order for heat pumps to become mainstream, the government must tackle three major stumbling blocks: the high up-front costs; generally low insulation of the house; and the negative word of mouth from faulty installations.
“Heat pumps are rarely defective,” says Lowes. “So when you hear horror stories, it’s usually because of bad advice or a bad installation.”
All heating systems work best in well-insulated homes, Lowes says, but this is especially true of heat pumps, which provide a steady, gentle source of heat to maintain an even temperature, rather than the draughty pressure of fossil fuels, and buildings need to get warm.
A heat pump from Vaillant. Photo: Octopus Energy / PA
“It’s a myth that heat pumps can’t work in old houses or townhouses – they might just take a little more work. Even if interior wall insulation is not possible, a heat pump can still work – maybe you just have to get a bigger one, ”he says.
After the collapse of the government’s Green Homes Grant program, the cost of home insulation overhauls would put many homes out of the running for a low-carbon heating system.
Perhaps the biggest challenge facing the heating revolution is the army of trained installers it needs, says Mark McManus, managing director of heat pump manufacturer Stiebel Eltron UK.
“If there’s a problem in the industry, it’s probably the skills gap,” he says. “There are few well-trained installers in the UK. But once that skill gap is closed, there will likely be better service and more competition, which could lead to further cost reductions. “
To close the gap, the heat pump association has launched a new program that could theoretically train up to 40,000 installers per year.
The steps to revise the plumber training pathway were welcomed by Economic Secretary Kwasi Kwarteng as “crucial” to fuel the government’s low-carbon ambitions and create more jobs in the green economy.
“There is a transition and that is our focus and we want to try to help people make that transition,” he said.