Air Source vs Ground Source Heat Pumps for Business
For most UK commercial sites, an air source heat pump (ASHP) is the practical choice. It costs less, goes in faster and needs almost no groundwork. A ground source heat pump (GSHP) is more efficient across the winter, so it can win on running costs. But it needs land for trenches or boreholes, a bigger budget and a longer project. The right answer depends on your site, your building’s heat demand and how long you will own it.
This guide compares the two on the criteria that decide business projects: capital cost, efficiency, space, planning, grant funding and risk. It also covers how heat pumps fit alongside EV charging, solar and battery storage on the same site.
TL;DR
ASHP: lower upfront cost, small footprint, quick install. It is the most common type in the UK.
GSHP: higher year-round efficiency because ground temperature is stable, but it needs land and groundwork.
Funding: the Boiler Upgrade Scheme offers £7,500 towards either type in England and Wales, for systems up to 45 kWth.
Performance: design quality, insulation and emitter choice often matter as much as the heat source.
Site-wide view: electricity demand from heat pumps and EV chargers should be planned together, not separately.
Table of Contents
How the two types work
Both types move heat rather than create it. A refrigerant circuit collects low-grade heat from a source, raises its temperature with a compressor and delivers it to your heating system.
The difference is the source. As the Parliamentary Office of Science and Technology explains in its heat pump briefing, air source units use a fan to pass outside air across an evaporator, while ground source units extract heat from the ground through buried pipework.
For a business, that one difference drives almost everything else: the size of the outdoor installation, the disruption, the cost and the seasonal efficiency.
Side-by-side comparison
Criterion | Air source (ASHP) | Ground source (GSHP) |
Typical installed cost (home-scale guide) | About £12,000 | About £15,000 |
Seasonal efficiency | Lower and more variable | Higher and more stable |
Outdoor space | A unit or units on a pad, wall or roof | Trenches or boreholes, plus a clear area |
Disruption | Low | Significant groundwork |
Planning | Noise and siting are the main triggers | Usually less visible, but ground works need assessing |
Boiler Upgrade Scheme grant | £7,500 | £7,500 |
Best fit | Most offices, shops, hotels, depots, retrofits | Sites with spare land, long ownership, high steady heat demand |
The cost figures come from the Energy Saving Trust comparison, which is written with homes in mind. Commercial systems vary widely with capacity, so treat these as a relative guide, not a quote. A larger building can multiply both figures, and the gap between the two types often widens as ground works scale up.
Efficiency: where ground source wins
Ground temperature stays steadier than air temperature through the year. That is the whole efficiency argument. On a cold January night, an air source unit is pulling heat from freezing air, while a ground loop is still drawing from soil that stays relatively warm.
The Energy Saving Trust notes that a ground source system is likely to be more efficient than an equivalent air source one, which means lower running costs and lower CO2 emissions, at a higher installation cost. In its summary of UK field data, average seasonal performance factor (SPF) for ground source systems reached around 3.31 by 2022, while air source systems often stayed nearer 2.7. An SPF of 3.31 means about 3.3 units of heat for each unit of electricity over a year.
Two cautions apply before you read that as a verdict.
Averages hide the spread. A well-designed ASHP can outperform a badly designed GSHP. The in-situ performance research, drawn from metered UK installations, compares real-world results with the figures systems were designed to deliver. The lesson is that the quality of design and installation shapes the outcome as much as the hardware.
Datasheet figures are not site figures. Manufacturer efficiency ratings are measured under set conditions. Your building has its own heat loss, flow temperatures and usage pattern. Ask any installer for a site-specific performance estimate, with its assumptions written down, before you compare quotes.
Cost: the upfront gap and the payback question
An ASHP is cheaper because there is less to build. A GSHP needs either long horizontal trenches or deep vertical boreholes, and that groundwork is the extra cost. The Energy Saving Trust confirms that ASHPs are the most common type in the UK because they are usually cheaper and involve much less disruption to install.
The question for a business is not which is cheaper to buy, but which costs less over the period you will use the building. Work it through like this:
Estimate annual heat demand from your current gas or oil bills, adjusted for any insulation upgrades planned.
Ask for an installed cost for each option, including groundwork, controls, any electrical upgrade and commissioning.
Ask for a modelled running cost at your current electricity tariff, using the seasonal efficiency each installer expects.
Deduct grant funding where you are eligible.
Compare over your ownership horizon. A tenant on a five-year lease and a freeholder planning to stay for decades are different cases.
A GSHP often makes the most sense where the extra capital is recovered through lower bills over a long hold, and where the land is already available or already being dug up for another reason, such as new-build groundworks.
Grant funding: the Boiler Upgrade Scheme
The current scheme treats both technologies equally. According to GOV.UK’s grant listing, the Boiler Upgrade Scheme gives £7,500 towards an air source heat pump and the same for a ground source heat pump. It covers homes and small and medium non-domestic buildings in England and Wales, and the listing shows a closing date of 30 December 2029.
The key rules for businesses, from Ofgem’s installer guidance:
The installation must be carried out by an MCS-certified installer.
Capacity per system is capped at 45 kWth.
Grants are paid as an upfront discount, so the installer claims the voucher rather than you.
Because the grant is the same for both types, it covers a larger share of an ASHP’s cost than of a GSHP’s. That narrows the practical price gap less than you might hope, so do not assume the grant tips the balance.
Scotland and Northern Ireland have separate arrangements, so check the schemes that apply in your nation before you commit. Check the current scheme rules on GOV.UK too, as terms can change.
Larger sites and the 45 kWth cap
A business park, hotel or depot can need far more than 45 kWth. The practical options are to split the load across several smaller units, each within the cap, or to consider a shared ground loop serving more than one building. A shared loop can allow higher total capacity, but it needs legal and hydraulic agreement between owners or tenants, and that coordination adds time to feasibility. Raise it early.
For public sector bodies and larger organisations, the Crown Commercial Service’s Demand Management and Renewables agreement includes a lot for heat pump projects covering both air source and ground source, which can serve as a structured procurement route.
Space and planning
Space
An ASHP needs a clear spot outdoors with airflow around it: a pad at ground level, a wall bracket or a flat roof. A GSHP needs enough accessible land for the ground loop. Horizontal loops take a large area. Vertical boreholes take less surface area but need drilling rigs, access and a budget for the drilling.
If your car park, yard or landscaped area is the only open space, check what lies beneath it first. Services, drainage and future plans for the site, including EV charging bays, can all conflict with a ground loop.
Planning permission
Businesses should not assume that the permitted development rights homeowners enjoy will apply. Commercial buildings, listed buildings and conservation areas usually need explicit permission. For air source units, noise and distance from the site boundary are the common triggers. The Islington permitted development guide shows how a local authority sets out the conditions for air source units, and it is a useful example of the kind of detail to expect. Rules differ by council and nation, so speak to your local planning authority at the feasibility stage. A retrospective application can halt operations.
Get the building ready first
The heat source is only part of the system. The Parliamentary Office of Science and Technology points out that performance improves as the gap between the source temperature and the emitter temperature narrows. Heat pumps run at lower flow temperatures than gas boilers, usually up to around 55°C.
That has practical consequences for a business:
Insulation and draught-proofing reduce the heat you need, so you can buy a smaller, cheaper system.
Larger or lower-temperature emitters, such as underfloor heating or oversized radiators, let the heat pump run efficiently.
Accurate heat-loss calculations prevent oversizing, which wastes capital, and undersizing, which leaves you cold.
A good installer will survey for all of this. If a quote arrives without a heat-loss calculation, treat it with caution.
Which one suits which business?
Choose air source if:
You are retrofitting an existing office, shop, school or hotel with little spare land.
You want the lowest upfront cost and the shortest disruption.
You may sell, lease out or redevelop the site within a decade or so.
You have a flat roof or yard where units can sit and meet noise requirements.
Choose ground source if:
You own the site for the long term and have a large open area, or are developing a new-build.
Your heat demand is high and steady, such as a leisure site or a care facility.
Lower running costs and stable winter performance matter more than the upfront bill.
You can manage the longer lead time for groundwork and design.
Consider a hybrid or phased approach if a single building has mixed demand. Some sites start with air source on one building and plan ground loops for new phases.
Plan heating alongside EV charging
A heat pump adds electrical load. So does every EV charger. Put both on a site with a limited connection and you can hit the capacity ceiling quickly, which is when grid upgrade quotes appear.
Experts increasingly treat heat pumps as part of a wider energy strategy, evaluating them next to solar PV and battery storage, since on-site generation can offset the electricity a heat pump uses. The CCS agreement above groups these technologies together for the same reason.
For a fleet or workplace site, the sensible order is to map your total future demand, then decide what to electrify first and how to balance the load. Our guides on avoiding costly grid upgrades with smart charging and battery storage for EV charging hubs and fleets cover the charging side of that calculation.
Our perspective
We are an EV charging company first, so we come at heat pumps from the electrical side of the site. Most of the businesses we speak to share one problem: a finite grid connection and several things they want to electrify. Whether you pick air or ground source, the heat pump becomes one more load competing with your chargers.
Our advice is to settle the electrical picture before you settle the heat source. Look at the connection capacity, the likely EV charger count over the next five to ten years, and whether solar PV or battery storage could ease the peaks. We can help commercial customers assess solar PV, battery storage and heat pumps alongside charging, and load management is part of how we design charging projects.
On the heat source itself, we would not push every business towards the more efficient option. For most retrofit sites, air source is the realistic starting point, and the money saved on groundwork can go towards insulation or other upgrades. Ground source earns its place on long-hold sites with land to spare. Either way, insist on a site-specific design, not a datasheet promise.
— Swift Charging
Plan your site’s energy in one go
If you are weighing heat pumps while also planning chargers, it helps to see the whole site at once. Our energy solutions for businesses page explains how we assess solar PV, battery storage and heat pumps alongside charging. If charging is the immediate need, start with a commercial EV feasibility review and we will look at your site, your connection and the funding you may be eligible for.
FAQ
Is a ground source heat pump worth the extra cost for a business?
It can be, but mainly on sites you will own for a long time, with land available and high, steady heat demand. Field data shows ground source systems perform better across the year on average, which lowers running costs. Compare modelled bills over your ownership period, not just the installation price.
Do air source and ground source heat pumps get the same grant?
Under the Boiler Upgrade Scheme, yes: £7,500 for each, in England and Wales, for systems up to 45 kWth installed by an MCS-certified installer. Eligibility depends on your building and property type, so check the current rules on GOV.UK before you commit.
Do air source heat pumps work in cold weather?
Yes, they extract heat from air even when it is cold, though efficiency falls as the temperature drops. That is why design matters: a well-sized system with suitable emitters and good insulation performs far better than a poorly specified one.
Will I need planning permission for a commercial heat pump?
Often, yes. Commercial, listed and conservation-area buildings usually need explicit permission, and for air source units noise and boundary distance are the usual concerns. Talk to your local planning authority early in the feasibility stage.
Can I run a heat pump and EV chargers on the same connection?
Sometimes, but you should check the capacity first. Both add electrical load, so a load assessment, smart load management and possibly on-site generation or storage can prevent an expensive grid upgrade.
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