The Greens’ heat pump plan won’t work

‘I’m literally in the process of getting quotes’ may well make it into the pantheon of feeble political excuses alongside ‘I did not inhale’ or ‘I was just watching badgers’. They were the words uttered by Green party co-leader Carla Denyer to explain why her home is still heated with a gas boiler rather than a heat pump – something her party advocates for others. She went on to say that she has some quotes for heat pumps in her email inbox but that she has had to put the project ‘on pause’ during the general election campaign.

When Denyer does get around to opening those emails – which I suspect won’t be in the flat above No. 10 – she may gain insight into why most homeowners have been resistant to politicians trying to persuade them to install a heat pump. She may also come to realise why her own party’s manifesto is somewhat over-hopeful in what it aims to achieve.

Up until the end of April this year, the government had paid out on 34,016 applications under its Boiler Upgrade Scheme – which offers grants of up to £7,500 to homeowners to install heat pumps. The average cost of installation – without reduction from the grant – was £13,318 in the case of air source heat pumps and £27,532 in the case of ground-source heat pumps. That compares with around £2,000 for purchase and installation of a new gas boiler.

Remember how the green lobby kept telling us that heat pumps were going to get cheaper as they made the transition from a niche product to a mainstream one? It isn’t happening. It may be that solar panels have come down in price sharply over the past decade, but heat pumps are on a very different cost trajectory. Someone, though, needs to tell the Green party’s manifesto-writers. The party says that in the improbable event that it made it into government it would allocate £9 billion over the next five years for ‘heating systems (e.g. heat pumps) for homes and other buildings’.

But how far would the money really go? There are 28 million households in Britain. If you divide the Greens’ £9 billion pot, it leaves you with just £320 per household – and that excludes any money for the ‘other buildings’ which the Green party wants to move onto green energy. In other words, the money allocated by the Greens wouldn’t get anywhere close to covering the cost of fitting heat pumps in all of Britain’s homes.

The Green are also promising £29 billion over five years to supposedly lift homes to a ‘B’ grading on an Energy Performance Certificate (EPC). That would work out at just over £1,000 per home. By contrast, the government quango, the Energy Savings Trust, estimates the average cost of fitting insulation to Britain’s 7.8 million homes with solid walls at between £7,500 and £12,000. And that, on its own, is highly unlikely to help an old home achieve a ‘B’ rating on an EPC.

The Green party’s plan to transform Britain’s homes with public money is nothing more than a fantasy. Carla Denyer might have realised that if she had obtained her heat pump quotes before her party wrote its policy.