Boiler Upgrade Scheme applications more than doubled year on year after grant increase

Applications to the Boiler Upgrade Scheme in April 2024 were up 93% year on year, according to ScottishPower, which described "applications in April 2024 being up 93% year-on-year"¹. Mitsubishi Electric reported the same month's applications "more than doubling in April this year compared to the same month in 2023 since grants increased from £5,000 to £7,500"². The Department for Energy Security and Net Zero increased the heat pump grant available to households by 50%¹, taking the maximum from £5,000 to £7,500 in October 2023⁴. The Committee of Public Accounts records that the grant had been £5,000 to £6,000 between May 2022 and September 2023, and that DESNZ raised it to £7,500 per household in October 2023⁵.

The scheme provides households in England and Wales with an up-front grant of £7,500 towards replacing fossil fuel heating with a heat pump or biomass boiler⁵. Uptake before the increase was well below expectation: nearly 18,900 heat pumps were funded through the scheme between May 2022 and December 2023, less than 40% of the 50,000 expected installations, leaving DESNZ underspent by £100 million in the scheme's first year⁵. At around £11,600, an average heat pump was then about four times the price of a gas boiler, which typically cost £2,500 to £3,000⁵.

Demand continued to rise after April. Mitsubishi Electric reported "12% higher uptake in September 2024 than August 2024"². ScottishPower said it had completed 3,000 heat pump installations over 18 months and had doubled its installation capacity by appointing a second provider focused on the Boiler Upgrade Scheme¹.

"The way we heat our buildings accounts for a third of carbon emissions in the UK, so encouraging the adoption of renewable heating alternatives like heat pumps is critical to achieving the challenging legal targets ahead of us."

Survey work published by Mitsubishi Electric and Censuswide, polling 2,025 homeowners in July 2024, found 79% used a gas boiler and just 4% used an air source heat pump, while 73% said they did not know enough about low-carbon heating to decide on switching². Of those surveyed, 44% wanted a grant covering installation costs, and 39% felt there was a lack of evidence on long-term cost savings².

Why it matters for households

The grant level is the single largest lever on the upfront cost of replacing a fossil fuel heating system in England and Wales, and the April 2024 figures show that household decisions respond to it. For a home weighing up a heat pump against a replacement boiler, the difference between a £5,000 and a £7,500 contribution is £2,500 off the installation bill. The Boiler Upgrade Scheme grant amount is fixed, so the remaining cost falls to the household.

Running costs are a separate question from installation costs. The Committee of Public Accounts found heat pumps more expensive to run than boilers because electricity is priced higher than gas, and that DESNZ had delayed plans to rebalance electricity and gas costs by nearly two years⁵. Mitsubishi Electric's research found that if electricity were cheaper relative to gas, 44% of homeowners said they would consider or immediately switch to a heat pump². A household's energy independence therefore turns on two things the sources treat separately: the capital grant, which has risen, and the running cost gap, which has not closed.

Eligibility also changed. DESNZ removed the requirement for minimum loft and cavity wall insulation standards to apply for a grant, effective 8 May 2024, leaving insulation as the householder's choice⁵. The Committee noted DESNZ had not published additional evidence on how that choice affects energy bills⁵. Households can check whether a gas boiler affects eligibility and how the application works.

What happens next

The Autumn Budget allocated £3.4bn to heat decarbonisation, including the Warm Homes Plan and further funding for the Boiler Upgrade Scheme². The government has committed an initial £3.4 billion for financial years 2025-26 to 2027-28 for the Warm Homes Plan⁶. The full Warm Homes Plan was launched in January 2026, with £15 billion of public investment across the UK over financial years 2025-26 to 2029-30, which the government said would upgrade up to 5 million homes with solar, batteries, heat pumps and insulation⁶.

The Energy Company Obligation, the supplier-funded scheme that has delivered most energy efficiency measures, will have its funding end in March 2026, with measures continuing until the end of 2026⁶. The government has a target of 600,000 heat pump installations a year by 2028⁵. DESNZ's evaluation of Boiler Upgrade Scheme take-up among different socio-economic groups was due to report interim results in the second half of 2024⁵; those findings have not been reported in the sources.

Sources6 cited

1. At ScottishPower we've reached 3,000 heat pump installs | Gas and Electricity Company | ScottishPower, scottishpower.co.uk
2. [](https://les.mitsubishielectric.co.uk/latest-news/8-out-of-10-homeowners-still-using-gas-while-73-unaware-of-low-carbon-alternatives), les.mitsubishielectric.co.uk
3. Heat pumps – the financial tipping point | Mitsubishi Electric, les.mitsubishielectric.co.uk
4. Green home statistics - Uswitch, uswitch.com
5. Decarbonising home heating - Committee of Public Accounts, publications.parliament.uk
6. [](https://researchbriefings.files.parliament.uk/documents/CBP-9889/CBP-9889.pdf), researchbriefings.files.parliament.uk