Delivering retrofit ground source heat pump installations at scale is key to achieving our carbon reduction targets – 80% of the building stock that will exist in the UK in 2050 has already been built. By engaging the rented and owner-occupier sector to deliver community-wide ‘heat the street’ schemes, Kensa is future-proofing our buildings of yesteryear.
Approach
Kensa’s philosophy for retrofit private housing heating upgrades is for a street-by-street, area-by-area basis, rather than house-by-house. This approach has significant benefits, including:
Working in areas of a single decision-maker, i.e. privately owned blocks of flats and estates, Kensa’s approach ensures government subsidy can allow large numbers of people to connect at the same time.
Mimicking a traditional gas framework, Kensa’s innovative Shared Ground Loop Arrays link a series of boreholes to multiple properties via an ambient temperature distribution system.
Each property then has an individual Kensa Shoebox heat pump wired to their own electricity supply, which upgrades the low temperature heat for heating and hot water within their dwelling.

read more
The advantages of Shared Ground Loop Arrays in new builds:
- Split-ownership of ground arrays provides a funded option;
- Exempt from Heat Network Metering & Billing Regulations;
- Extremely low CO2 emissions;
- Easy carbon & building regulations compliance;
- No NOx, SOx or particulates emissions;
- Lowest energy bills – slightly lower than mains gas, significantly lower than air source heat pumps, LPG & oil;
- Householders able to switch energy suppliers;
- No district heat losses;
- Potential for free summer cooling;
- Scalable and flexible district size can be deployed in sections as the development progresses;
- Ultra-efficient and reliable.
Hot Water Cylinder & Thermal Store

- Sunamp’s super-compact Heat Battery technology fits perfectly with the Shoebox heat pump to provide a clean, efficient and cost-effective thermal energy storage solution.
- Kensa has partnered with leading cylinder manufacturer, Advance Appliances, to design and produce stainless steel mains pressure cylinders featuring enhanced surface area coils specifically for ground source heat pumps.
Subsidies
Split Ownership model
By allowing ‘split ownership’, Government has created a significant catalyst for energy-efficient new build developments featuring Shared Ground Loop Arrays, with costs no longer borne by the housing provider.
This eliminates the key barrier to deployment – the expense of the ground array – and allows Kensa to mimic long-standing ‘split ownership’ arrangements in the gas sector with the underground infrastructure owned and maintained separately from the heat pump installed inside the properties. Kensa’s model sees the housing provider fund the heat pump (which is sold with the property and maintained by the purchaser) whilst the ground array is fully funded.
Typical Project Costs
Financial illustration (retrofit of 24 houses):
Based on Kensa’s fully funded ground arrays option.
Total Cost of Installation (Paid by Homeowners) | £432,270 |
Kensa Utilities Capital Contribution (RHI-linked) | £229,079 |
Net Cost of Ground Source Heat Pumps & Cylinders* | £203,190 |
*Avoided costs should be subtracted from this figure. The deduction or counterfactual should include the costs of replacing the existing heating with night storage heaters or a boiler.
Please note: The Non-Domestic RHI has now ended. Visit Kensa Heat Pumps to explore current funding options.
Funding
The below outlines the mechanism for housing providers wishing to utilise Kensa’s fully-funded Shared Ground Loop Arrays:

read more
Warranties
- 5 year warranty for the heat pump unit.
- 2 year warranty for the controller and water pumps.
- 2 year internals warranty.
Extended warranties are available on request.
Property’s featuring Kensa’s Shared Ground Loop Arrays will provide end users with numerous unique benefits over traditional Heat Networks:
Lower fuel bills
GSHP’s produce 3-4kWh of heat energy for every 1kWh of electrical energy used, making them 300-400% efficient. Compare this to a typical boiler, which is just 90% efficient. Kensa’s ground source heat pump systems offer the lowest fuel costs.
Lower emissions
Because a GSHP extracts so much “free” energy from the environment, this enables CO2 emissions to be lower than any other type of heating system.
Minimal maintenance
GSHP’s don’t require annual servicing or maintenance, and have an expected lifetime of 20 years.
Energy independence
With an individual ground source heat pump in each property, homeowners are in complete control of their own heating and energy bills, enabling easy energy tariff switching and payment only for their own heat consumption.
DOWNLOAD PURCHASER'S GUIDE

Free cooling & no overheating
With heat being generated at the point of use (inside each dwelling) the ‘heat’ circulating the property is low temperature, therefore there are no heat losses from the system to contribute to overheating in risers and corridors. The low temperature system also allows for free passive cooling to be introduced, creating a comfortable living environment all year round.
Year round supply
1m below the surface the ground temperature remains a fairly constant 8-10°C all year round, ensuring your heat supply is constant and reliable; unlike air source heat pumps, which are impacted by external fluctuating air temperatures causing higher bills when heat is most needed.
Related Content
This Kensa Contracting commissioned animation depicts the key stages for the installation of Kensa Shoebox ground source heat pumps into individual flats in tower blocks, connected to shared ground loop array boreholes. For more information on this application click here. *Please note: the Non-Domestic RHI funding stream mentioned in this video has now expired. Explore…
Summary: Kensa looks at what air pollution is and the culprits that contribute to it – impacting public health and the economy. We also look at how ground source heat pumps, as electrically-driven heating systems, can reduce air pollution. Read more at KENSAHEATPUMPS.COM A 2020 study from CBI Economics & Clean Air Fund…
Download a short guide to ground source heat pumps for purchasers and end users, including benefits and costed examples.