Commercial heat pump grants, mapped to the funding your building actually qualifies for
Commercial heat pump grants are the single most misunderstood part of decarbonising a non-domestic building, and that confusion costs organisations real money. The headline £7,500 Boiler Upgrade Scheme that everyone has heard of is domestic-only and does not touch a commercial property, which leaves a lot of facilities, estates and energy managers assuming there is no funding at all. There is, but it lives in a different set of schemes with different rules, and the trick is matching your building, your sector and your tax position to the right route before you commit a penny of capital. That is what this page, and our work, is built around: leading with the funding question, then sizing and delivering a system that is designed from the outset to qualify for it.
The case for acting is straightforward. Heat is roughly a third of UK carbon emissions and the gas boiler is usually the single largest source in a commercial building. Gas prices remain volatile and the Climate Change Levy adds cost on top, so heating budgets swing unpredictably year to year, while ageing boiler plant nearing failure forces the decision anyway and landlords face MEES and EPC pressure. A commercial heat pump replaces on-site combustion with electrified heat at an SCOP of typically 3.0 to 4.0 for air-source and often above 4.0 for ground-source, meaning three to four units of heat for every unit of electricity. The funding routes below reduce the capital that has to be recovered, which is exactly why getting the grant strategy right comes first.
The funding landscape for commercial heat pumps
There is no single headline commercial grant, but there are several substantial routes, and most buildings qualify for at least one. Public-sector bodies, NHS trusts, schools, colleges, universities, local authorities and emergency services, apply to the Public Sector Decarbonisation Scheme (PSDS) run by Salix Finance for DESNZ, which funds the cost over and above a like-for-like fossil-fuel replacement and takes a whole-building view, with capital grants ranging from tens of thousands to multi-million pounds. Eligible industrial sites and data centres in qualifying SIC codes, manufacturing, recovery and recycling, controlled-environment horticulture, industrial laundries, can look to the Industrial Energy Transformation Fund (IETF) Phase 3, with up to £185m across the fund to 2028, an SME minimum grant of £75,000 and typically 30 to 50% intervention. Multi-building and campus schemes have the Green Heat Network Fund (GHNF), a capital grant of up to 50% of eligible costs, well suited to councils, hospitals and large mixed-use developments.
Crucially, every business, public or private, can also use capital tax relief, and for private commercial buildings this is often the single most valuable lever available. Because heat pumps are plant and machinery, full expensing allows a company within UK corporation tax to deduct 100% of new, unused qualifying kit in the first year, uncapped and permanent from April 2026, saving up to 25p in tax for every pound spent at the 25% rate. Sole traders and partnerships rely instead on the Annual Investment Allowance, which relieves up to £1m of qualifying spend at 100%. A portion of ancillary wiring can sit outside full expensing yet still qualifies for the AIA. The point that matters: a grant and capital allowances are not mutually exclusive, and we map exactly which routes combine for your project rather than leaving you to discover the hard way that the £7,500 domestic grant does not apply. The full detail sits on our grants and funding page.
How we size and design systems so they qualify
Funding follows credible numbers, so the design and the grant case are the same piece of work. We never size from floor area. Sizing comes from a proper heat-loss survey and at least 12 months of your gas or oil consumption, because a competitive grant application and an honest business case both live or die on real demand data. The single biggest lever on performance is flow temperature: every degree we can shave off lifts the SCOP, so we design for low flow temperatures of 45 to 55C wherever the emitters allow, and specify to BS EN 14825 (SCOP) and BS EN 14511 (rated COP) so the performance figures in your funding bid are directly comparable to any compliant supplier.
A commercial air-source system usually lands in the 40 to 500 kW thermal band, delivered as a single unit up to a cascaded bank of 4 to 12 modular units. Ground-source runs 50 to 1,000 kW thermal on a borehole array typically 100 to 200m deep, carrying higher capital but a higher and more stable SCOP. A hybrid design pairs a 60 to 400 kW heat pump cascade with a retained or new peaking boiler, letting the heat pump carry 70 to 90% of annual load while the boiler covers the rare coldest days, usually the most cost-effective and most fundable retrofit because the capital ask is smaller. We model these side by side from your data so the chosen route is a deliberate, evidenced decision tied to whichever grant or tax relief the scheme is built to qualify for.
Costs and payback after grant (illustrative)
Installed cost is driven by technology, scale, the emitter upgrades required and any electrical supply work. As a guide, a commercial air-source project typically runs £60,000 to £600,000 with a simple payback near 8 years before any grant; ground-source £150,000 to £2,000,000 or more at a payback near 11 years before grant; and a hybrid retrofit £70,000 to £500,000 at a payback near 7 years, the shortest of the main routes. These are pre-grant figures. A PSDS, IETF or GHNF award meets a significant share of the capital, and full expensing or the AIA then reduces the after-tax cost further, so the effective payback after funding is materially shorter than the headline. We model the full installed cost and the tax treatment together on our cost guide, always from your own consumption data at current and forecast prices rather than an optimistic estimate.
Compliance and sector considerations
Grant eligibility and compliance are intertwined. For systems up to 45 kWth, MCS certification (or a recognised commercial equivalent) is required to access most grant routes, and we hold MCS 025 installer competency; above 45 kWth we design to CIBSE and BSRIA standards. All refrigerant work is carried out by F-Gas certified engineers under the UK F-Gas Regulation, with the high-GWP phase-down steering modern units toward lower-GWP R32 (A2L) and, for higher duties, natural refrigerants such as R290, CO2 and ammonia, which carry DSEAR and ATEX siting requirements we design for. Systems are built to BS EN 378. Where a hybrid retains a gas boiler, Gas Safe is also in scope. Most air-source installs fall under permitted development but are subject to size, siting and noise limits, so a BS 4142 acoustic assessment is commonly required; listed buildings and conservation areas need consent, and ground-source open-loop systems abstracting groundwater need an Environment Agency permit. Large heat pumps add real electrical load, so we confirm DNO supply capacity early because a supply upgrade can be the longest-lead item, which matters acutely when a grant scheme carries a fixed completion deadline.
How we approach the grant application and the project
We start with your half-hourly meter data and 12 months of fuel consumption, then build the funding case and the engineering case in parallel rather than in sequence. We assess which schemes you qualify for, map how a capital grant stacks with full expensing or the AIA, and design the system to the standards a funder expects so the bid stands up to scrutiny. We get the G99 grid application and any DNO enquiry in early so the long-lead item does not derail a fixed grant deadline, survey existing emitters so you do not pay for a strip-out you do not need, and submit the application built around your scheme rather than the other way round. You receive a fixed-price proposal with running cost and carbon modelled from your own data, an insurance-backed warranty, and a clear statement of which grant or tax route the project is built to qualify for. We would rather lose a job to honest maths than win it on a number we cannot stand behind.
An illustrative example
As an illustrative composite based on typical UK projects, and not a real named client: a council-owned leisure centre with a swimming pool, sports hall and year-round heating and hot-water load on an end-of-life gas boiler secured Public Sector Decarbonisation Scheme funding for its heat decarbonisation. The design was a 450 kW ground-source heat pump on a borehole array, delivering heating in winter and supporting space cooling in summer, with around 1,050,000 kWh of heat a year at an SCOP near 4.1, saving roughly 190 tonnes of CO2 annually. The PSDS grant covered the bulk of the capital over the like-for-like boiler-replacement cost, so conventional payback was not the relevant measure for the council, and the stable year-round SCOP plus summer free-cooling made it a best-practice case in its net-zero strategy. The figures are illustrative and depend entirely on your building, your sector eligibility and the scheme rules in force at the time.
The right first step is to find out which funding you qualify for. Read the grants and funding routes in detail, work through the cost guide, browse the FAQs, then request a free feasibility built from your meter data and mapped to the grant route that fits your building.
