Commercial Heat Pumps Explained: Costs, COP and When They Pay

What a commercial heat pump actually does

Commercial heat pumps are the one measure that removes the gas you burn on site, and for most UK businesses that gas is the largest chunk of carbon nothing else can touch. A heat pump moves heat rather than making it: it extracts low-grade warmth from the air or the ground, concentrates it with a compressor, and delivers it to your space heating, hot water or process at a useful temperature. Because it is moving energy rather than burning fuel, a good system delivers 3 to 4 kWh of heat for every 1 kWh of electricity it draws. That ratio is the coefficient of performance, or COP, and it is the single number that decides whether a heat pump stacks up for your building.

This guide sets out the real costs, what COP means for your bills, the funding routes that genuinely apply to commercial buildings, and an honest view of when a heat pump pays and when you should wait. If you want the wider picture of how heat fits alongside solar, storage and EV charging, our heat pumps for business pillar covers the technology in full.

COP, SCOP and why the number on the datasheet is not the number you get

The COP on a manufacturer’s datasheet is measured under ideal lab conditions. What matters for your business is the seasonal figure, SCOP, which averages performance across a real heating season including cold snaps when the pump works hardest. A well-designed commercial air-source system typically returns a SCOP of 3 to 3.5; a ground-source system on a suitable site can reach 4 or higher because ground temperature is stable year round.

The practical rule is simple. The lower the temperature you ask the system to deliver, the higher the COP. A heat pump feeding oversized radiators or underfloor heating at 40-45C runs far more efficiently than one forced to hit 70C to match an old gas boiler flow temperature. This is why sizing and emitter design, not the badge on the unit, decide your running costs.

Metric	Gas boiler	Commercial air-source heat pump
Efficiency	85-92%	COP 3-4 (300-400%)
Fuel	Mains gas	Electricity
Scope 1 carbon	Direct emissions	Zero on site
Typical flow temp	70-80C	40-55C for best COP
Best paired with	-	Fabric upgrade, solar PV

What commercial heat pumps cost

Commercial heat pump project values run from roughly £30,000 for a small building up to £750,000 for a large factory or multi-building estate, with system sizes typically spanning 30 kW to 1 MW of thermal output. The spread is wide because the cost is driven by your heat demand, the emitters you already have, and whether you go air-source or ground-source.

Air-source is the default for most commercial buildings: lower capital cost, external units that need space and airflow, and no groundworks. Ground-source suits sites with land or the budget for boreholes and a steady, high load; it costs more upfront but the higher, more stable COP can justify it over a long life. Running cost then depends on the gap between your electricity price and your gas price. UK commercial electricity now sits at 25 to 45p per kWh against cheaper gas, so a heat pump only beats a gas boiler on running cost when the COP is high enough to close that gap. At a COP of 3.5 and typical prices, most sites see lower or comparable running costs, and the economics improve sharply when the pump runs on self-generated solar rather than grid power.

For a full breakdown across every measure, including how a heat pump compares with solar and battery on payback, see our cost guide.

Funding: which schemes actually apply

This is where a lot of businesses are misled. The domestic Boiler Upgrade Scheme does not apply to commercial buildings, so ignore any quote that leans on it. The real commercial routes are:

• 100% Annual Investment Allowance and Full Expensing. Heat pumps qualify as plant and machinery, so a profitable company deducts the full capital cost from taxable profit and recovers roughly a quarter of it through corporation tax relief. This is the primary lever for owned kit.
• Public Sector Decarbonisation Scheme (PSDS) and Salix. The principal commercial heat-pump funding line for public bodies, schools, the NHS, colleges and councils, offering grant funding and interest-free loans.
• Industrial Energy Transformation Fund (IETF). Grants from £100,000 upward for energy-intensive manufacturing and industrial sites deploying efficiency and decarbonisation measures, including process heat.
• Regional and combined-authority grants. GMCA, WMCA and Growth Hubs periodically run SME decarbonisation rounds worth £1,000 to £50,000, sometimes with a free audit attached.

The grants and funding guide sets out eligibility and current windows for each. VAT is separately reclaimable for VAT-registered businesses.

When a commercial heat pump pays

A heat pump typically pays back in 7 to 12 years, which is longer than solar at 5 to 8 years or efficiency measures at 1 to 4. That is not a reason to avoid it; it is a reason to sequence it correctly. The payback lands at the shorter end of that range in three situations:

1. You are replacing an oil or LPG boiler. Oil and LPG are expensive per kWh, so the running-cost saving against a heat pump is much larger than against mains gas, and payback shortens accordingly.
2. Your gas boiler is at end of life anyway. When you are already facing a replacement, compare the heat pump against the cost of a new boiler, not against zero. On that basis the incremental cost is far smaller.
3. You run the pump on self-generated solar. Feeding a heat pump with solar power at a few pence per kWh instead of grid electricity at 25-45p transforms the running cost. This is why we design heat and generation together rather than as separate projects; the interaction is set out in our commercial solar pillar and paired with battery storage to shift stored solar into the evening heating load.

There is also the carbon case, which is often the deciding factor. On-site solar and efficiency cut your Scope 2 electricity emissions, but only a heat pump removes the Scope 1 gas emissions that flow straight into SECR reporting and customer ESG questionnaires. For a business fielding net-zero questions down its supply chain, that Scope 1 reduction can be worth more than the payback maths alone suggests.

When to wait

An honest specialist will tell you when a heat pump is not the right first move, and often it is not. Two common cases:

• Your building fabric is poor. A heat pump sized to a leaky, poorly controlled building has to work harder, run hotter and cost more. Fix the fabric and controls first so the system is sized to a lower, well-managed heat demand. This usually cuts both the capital cost and the running cost.
• You have not yet cut electrical waste or added solar. Because a heat pump increases your electricity demand, installing one before an energy audit and voltage optimisation means you may be paying grid rates for heat you could have run on cheaper self-generated power. The order that saves money is measure, generate, then electrify heat.

Compliance and grid connection

Systems up to 45 kW need MCS certification; larger installs follow CIBSE and commercial design standards. F-gas regulations govern refrigerant handling, and external units or ground-source boreholes may need planning permission. A heat pump adds electrical load, so larger systems require a G99 application to your DNO, and load management can often avoid a costly supply upgrade. Because DNO timescales run from weeks to many months, the application should go in early.

The honest summary

Commercial heat pumps are mature, bankable and, for many UK businesses, the only realistic route to removing on-site gas carbon. They pay back over 7 to 12 years, faster when they replace oil, coincide with a boiler replacement, or run on solar. The mistakes that ruin the case are predictable: sizing to an unimproved building, chasing a high flow temperature, banking on a domestic grant that does not apply, and buying heat before you have cut waste and added generation.

We assess your building, heat demand and load profile from your actual meter and gas data, model the heat pump alongside solar, storage and the funding routes that fit, and tell you honestly whether now is the right time or whether one measure should come first. For a costed, independent roadmap for your site, request a free assessment and we will show you the numbers before you commit to anything.