The Environment Agency's Chief Scientist's Group published a review of ground source heating and cooling in September 2024, covering the status of the industry, its policy history and its market. The report places the Boiler Upgrade Scheme (BUS) within a longer sequence of UK subsidy and certification arrangements, and records that grants for heat pumps increased in October 2023 following a consultation and review by DESNZ1.
The review describes the BUS as the current subsidy framework and refers to "the recent Boiler Upgrade Scheme (BUS) uplift in summer 2023"1. It does not set out the grant amounts before or after that uplift, and no figures for the summer 2023 change appear in the report. The October 2023 increase is described separately as following a consultation and review by the Department for Energy Security and Net Zero1.
Earlier support schemes are dated in the report. The domestic Renewable Heat Incentive closed to new applicants on 31st March 2022, and the Non-domestic RHI closed on 31st March 20211. The Low Carbon Building Programme ran from April 2006 and closed to new applications in May 20101. The Microgeneration Certification Scheme was transferred in April 2018 to MCS Service Company Limited and the MCS Charitable Foundation1.
On the wider market, the report states that 59,862 heat pump units were sold in the UK in 2022, an increase of 17,103 on 2021, a growth of 40%1. Ground source systems are put at 9% of the current UK heat pump market in England1. The report notes there is no single register of installed ground source heating and cooling systems in England, that its figures are best estimates, and that many apply to the UK rather than England, for which a multiplier of 78 to 80% is recommended1.
Installation counts by area are given in the report, including Salford (353), Glasgow City (274), Calderdale (241) and Sunderland (234), with Highland (4,751) and Argyll & Bute (2,764) also listed1. Density figures include Ceredigion, Mid Wales at 0.39% and Cotswold and Orkney at 0.34% each1.
"until the recent Boiler Upgrade Scheme (BUS) uplift in summer 2023"
Why it matters for households
The Boiler Upgrade Scheme is the main grant route for households replacing a fossil fuel heating system with a heat pump or biomass boiler, and the report confirms that its grant levels changed in summer 2023 and again in October 20231. For a household weighing up a heat pump against a gas boiler, the grant level at the point of application is a direct part of the upfront cost, and the report shows that level has moved more than once in a short period1.
The report also indicates how small the ground source segment remains: 9% of the UK heat pump market in England, against a government target of 600,000 heat pump installations a year by 2028, up from 55,0001. Ground source systems need outside space for boreholes or trenches, which shapes which homes can use them, and the report notes that since October 2023 closed-loop systems are regulated through the Environmental Permitting Regulations1. Households on the gas grid face separate eligibility questions, covered in Can I get the Boiler Upgrade Scheme grant if I have a gas boiler?, and the report does not resolve how the scheme will treat them in future.
What happens next
The report lists planned implementation of the Future Homes Standard in 2025, which it says effectively bans the installation of gas boilers in new homes, alongside possible amendment to the BUS or another subsidy framework, the place of hydrogen in the future UK energy economy, and decoupling of electricity price from gas price1. It states that UK Net Zero policies were evolving rapidly at the time of writing and that policy details should be checked at the time of reading1. No confirmed date for a further BUS change is given in the report.
Sources1 cited
- Ground source heating and cooling: status, policy, and market review, assets.publishing.service.gov.uk