Heat pumps could be the single largest step a household can take to reduce their carbon emissions while saving money on their bills. But many in Britain fear that, even though millions of homes across Europe have benefited from the shift away from gas or oil boilers, the UK’s draughty old homes could prove too great a challenge for the technology.
The concern is unsurprising given that the UK has some of the least energy efficient homes in Europe. A study by the smart home company tado° monitored 80,000 users across Europe to find how quickly properties lose heat when outdoor temperatures fall to zero. It found that UK homes lost on average 3C after five hours without heating, compared with just 1C in Germany and 0.9C in Norway.
The previous article in the series concluded that while in the vast majority of cases properties of any age can successfully make the switch from a gas boiler, improving insulation helps. So is it necessary to spend a lot on insulation and other mitigating measures to make a heat pump work?
The claim
Heat pump sceptics argue that while they might work in the well-insulated homes of Norway, Finland and Sweden, the UK’s relatively mild climate and historically high gas reserves have allowed energy efficiency standards to lag, meaning they will not be as effective in UK homes.
The devices rely on a constant flow of gentle warmth to build up to the desired temperature, which the unconvinced argue is harder to achieve in a draughty home.
Mike Foster, the chief executive of the Energy Utilities Alliance, a trade body that represents gas boiler manufacturers, told the Telegraph that the state of Britain’s housing stock meant heat pumps were unsuitable for up to 54% of homes currently using gas boilers without the eye-watering cost of retrofits.
He argued that while many neighbouring European countries were “ravaged by war” in the 20th century and needed to be rebuilt, the UK still has “an awful lot of buildings built before 1919”, which mostly have solid walls.
These can be particularly disruptive to insulate as doing so involves extensive building work. There can also be large upfront costs of for insulation of up to £12,000 when applied externally or £7,000 when added internally.
“When you have external walls like that, they leak heat, and they’re not ideal for heat pumps,” Foster told the paper. While experts point out that leaky homes are not ideal for any kind of heating, will the switch to heat pumps necessitate Britain spending billions on insulation?