Energies

Ground Source Heat Pumps UK — Costs, Grants, Savings, and How They Work

How ground source heat pumps work in the UK, installation costs, running costs, BUS grant, and whether they're right for your home.

Ground source heat pumps (GSHPs) are one of the most efficient ways to heat a home — extracting heat from the ground to provide heating and hot water. They cost more to install than air source alternatives, but they’re more efficient and quieter.

How Ground Source Heat Pumps Work

Component What it does
Ground loop Pipes buried underground that absorb heat from the earth
Heat pump unit Compresses the absorbed heat to usable temperatures
Distribution system Underfloor heating or radiators to heat your home
Hot water cylinder Stores heated water for taps and showers

The ground stays at a relatively constant 10–13°C year-round below a few metres depth, making it a reliable heat source even in winter.

Types of Ground Loop

Type How it works Space needed Cost
Horizontal loop Pipes laid in trenches (1–2m deep) Large garden — typically 2x the floor area Cheaper (£10,000–£20,000 for loops)
Vertical borehole Pipes in deep boreholes (50–200m) Small footprint — can work with limited space More expensive (£15,000–£30,000 for boreholes)
Pond/lake loop Pipes submerged in a body of water Requires a suitable body of water Variable

Costs

Cost element Typical range
Heat pump unit £5,000 – £10,000
Ground loops (horizontal) £5,000 – £10,000
Ground loops (borehole) £10,000 – £20,000
Installation and plumbing £3,000 – £6,000
Underfloor heating (if needed) £3,000 – £8,000
Hot water cylinder £500 – £1,500
Total (horizontal) £15,000 – £28,000
Total (borehole) £20,000 – £35,000
After BUS grant (£7,500) £7,500 – £27,500

BUS Grant (Boiler Upgrade Scheme)

Detail Information
Grant amount £7,500 (ground source)
Available in England and Wales
Runs until March 2028
Who can apply Homeowners (not new builds)
Requirements Valid EPC, replacing existing heating, MCS-certified installer
How it works Installer applies directly — you pay the reduced price
Air source grant £7,500 (same amount since 2024 increase)

Running Costs

Heating system Annual cost (3-bed detached)
Ground source heat pump £600 – £1,200
Air source heat pump £700 – £1,400
Gas boiler £800 – £1,400
Oil boiler £1,200 – £2,000
LPG boiler £1,500 – £2,500
Electric storage heaters £1,800 – £3,000
Direct electric heating £2,500 – £4,000+

COP (Coefficient of Performance)

System Typical COP What it means
Ground source heat pump 3.5 – 4.5 £1 of electricity produces £3.50–£4.50 of heat
Air source heat pump 2.5 – 3.5 £1 of electricity produces £2.50–£3.50 of heat
Gas boiler 0.9 £1 of gas produces 90p of heat
Direct electric heater 1.0 £1 of electricity produces £1 of heat

GSHPs maintain high efficiency even in cold weather because ground temperature stays constant — unlike air source pumps that lose efficiency when it’s coldest.

Annual Savings

Replacing Estimated annual saving
Gas boiler £200 – £600
Oil boiler £500 – £1,200
LPG boiler £700 – £1,500
Electric storage heaters £1,000 – £2,000
Direct electric £1,500 – £2,500+

Payback Period

Scenario Upfront (after BUS) Annual saving Payback
Replacing gas boiler (horizontal) £10,000 £400 ~25 years
Replacing oil boiler (horizontal) £10,000 £800 ~12 years
Replacing LPG (horizontal) £10,000 £1,100 ~9 years
Replacing electric heating (horizontal) £10,000 £1,500 ~7 years

Payback is fastest when replacing expensive fuels (oil, LPG, electric) and when combined with solar PV.

Is Your Home Suitable?

Requirement Detail
Outdoor space Horizontal: garden 2x floor area. Borehole: much less
Insulation Well-insulated homes benefit most. EPC C or above ideal
Heat distribution Underfloor heating is best; larger radiators work too
Garden access Digger access needed for trenching
Ground conditions Rocky ground is harder/more expensive
Planning permission Usually permitted development, but check

Best For

Situation Why
Rural homes off the gas network Replacing oil/LPG saves most
New builds Easy to install during construction
Large, well-insulated homes Maximum efficiency and savings
Homes with space for ground loops Cheaper horizontal installations
People planning to stay long-term Payback requires time

Not Ideal For

Situation Why
Small properties with no garden Need space for ground loops or boreholes
Poorly insulated homes Must insulate first — heat pump output is lower temperature
Short-term residents May not recoup investment
Tight budgets Significant upfront cost even with grant

GSHP vs ASHP (Air Source)

Feature Ground source Air source
Efficiency (COP) 3.5–4.5 2.5–3.5
Winter efficiency Stays high Drops in cold weather
Installation cost £15,000–£35,000 £8,000–£15,000
BUS grant £7,500 £7,500
Running costs Lower Higher
Noise Silent Outdoor fan noise
Space needed Large garden or borehole Small outdoor unit
Maintenance Minimal Minimal
Lifespan 20–25+ years 15–20 years
Visual impact None (underground) External unit visible

Maintenance

Task Frequency Cost
Annual service Yearly £100 – £200
Antifreeze check (ground loops) Every 5 years Included in service
System pressure check Annually Included in service
Major repair (compressor) Rare (10-15 years) £1,000 – £2,500

GSHPs are generally low-maintenance. The ground loops have no moving parts and can last 50+ years.

Summary

Feature Detail
Installation cost £15,000 – £35,000
BUS grant £7,500
Annual running cost £600 – £1,200
COP efficiency 3.5 – 4.5
Best for Off-grid homes, replacing oil/LPG, good insulation, space for loops
Payback 7–25 years depending on current heating
Lifespan 20–25+ years (loops 50+ years)
Maintenance £100–£200/year service