Shared Ground Loop Arrays

Kensa’s Ambient Shared Ground Loop Arrays (SGLAs) are an award-winning and pioneering approach to District and Communal Heating without the drawbacks of traditional Heat Network systems.

The unique design allows property owners and developers of two or more dwellings to realise the full potential of ground source heat pumps and receive Non Domestic Renewable Heat Incentive (RHI) payments for both new builds and existing housing stock, attracting external funding opportunities for fully funded ground arrays and ultra-low cost heat pumps.

Ambient Shared Ground Loop Arrays

What are Ambient Shared Ground Loop Arrays?

Kensa’s Ambient Shared Ground Loop Arrays (SGLAs) are a 5th generation ultra-low temperature Heat Network for use with Kensa Shoebox ground source heat pumps or Evo heat pumps.

Mimicking a traditional gas framework, a series of ground arrays, typically boreholes, are linked together to form a shared ground loop array acting as a heat energy source to multiple properties (District Heating) or multiple occupancy buildings (Communal Heating).

The shared ground loop system transfers ambient temperature low grade heat energy from the ground (-5°C to 20°C) to individual Kensa ground source heat pumps located inside each individual dwelling.

Each Kensa ground source heat pump then upgrades the ground’s heat energy to provide independently controllable heat and hot water to the property.

Kensa Shoebox Heat Pump

Before the launch of Kensa’s famed Shoebox heat pump, multi-occupancy developments such as apartments and tower blocks, were unable to benefit from ground source heat pump technology due to sizing and specification issues.

Developed with Shared Ground Loop Arrays in mind, the unique, ultra-small and ultra-quiet Shoebox range of heat pumps from Kensa Heat Pumps are typically installed under the kitchen sink or in an airing cupboard, creating a significant opportunity for social housing providers and developers to introduce the most effective and efficient renewable heating technology in multi-occupancy dwellings.

explore the shoebox

Communal ground loops with individual heat pumps are the most economic solution of all (at approximately £500/yr) and are also compliant with London’s key objectives in terms of air quality and carbon emissions. They combine several advantages: they are very energy efficient and do not require dedicated heat metering and billing.

Greater London Authority (GLA), ‘Low Carbon Heat: Heat Pumps in London’ (September 2018)

Shared Ground Loops Vs Heat Networks

Shared Ground Loop ArraysTraditional Heat Networks
+ Ambient loop - no heat losses- Heat loss through network
+ No overheating (Read more)- Overheating in risers & corridors
+ Independent billing- Requires split-billing
+ Independent heat - freedom to switch suppliers- Single heat energy provider
+ Receives Non Domestic RHI (Read more)- Complex funding claims
+ Deemed heat for RHI - no heat meters- Networked heat metering
+ No plant room - individual heat pump per dwelling- Large & unsightly central plant
+ Lowest bills- ESCO purchases energy
+ No servicing & minimal maintenance- Highly specialised servicing
+ Robust and reliable- Back up system required
+ Carbon compliant (Read more)
+ No emissions (Read more)
+ Free passive cooling (Read more)
+ Flexible and scalable
+ Planning exempt

Benefits: In Detail

Hover over the below interative image to find out more about the unique benefits of Shared Ground Loop Arrays from Kensa.

Decentralised Heat Networks

Connecting individual Kensa heat pumps installed within multiple dwellings (District or Communal) to a Shared Ground Loop Array circulating at a low temperature provides a unique and technically robust Heat Network, which in addition to qualifying for 20 years of income through the Non Domestic RHI, also offers significant operational benefits over traditional district Heat Networks.

The decentralised approach results in a more efficient system as there are no heat losses through the distribution pipework as the circulated heat through the Shared Ground Loop Array is at ambient temperature, with high-grade heat only generated at the point of use, and only when required; unlike traditional Heat Networks where heat is generated in a central plant and then circulated continually, thus leading to heat losses, and overheating in multiple occupancy buildings.

As such, with Kensa’s Shared Ground Loop Arrays there are no heat losses from the system to contribute to overheating in risers and corridors, a common issue with offices and apartment blocks. Furthermore, as the cold side infrastructure extends all of the way to the individual dwelling, it is easy to add passive cooling to the system.

Crucially, as each dwelling has its own ground source heat pump wired to its own electricity supply, the occupant is in full control of their heating, and billed independently; no tie-in’s to Heat Network contracts or issues of split billing, and complete freedom to switch energy supplier to ensure the best deal.

The Government recognises that GSHPs are likely to be a strategically important technology for decarbonising heat, and anticipates potential for significant growth in deployment of this technology through the period to 2050.

The Government is keen to support the deployment of GSHPs making use of shared ground loops. This route (shared ground loops) will improve investment confidence and ............. will also offer the greatest flexibility, encouraging a broad range of shared loop projects to come forward including new build and mixed use projects.

Department for Business, Energy & Industrial Strategy, 'THE RENEWABLE HEAT INCENTIVE: A REFORMED SCHEME: Government response to consultation', (December 2016)

How It Works

In Theory

This Kensa animation depicts the key stages for the installation of Kensa Shoebox ground source heat pumps into individual flats in tower blocks, connected to ambient shared ground loop arrays (boreholes).

In Practice

This Kensa time lapse shows the drilling of 25 shared ground loop boreholes for Kensa Shoebox heat pumps in 49 bungalows owned by Stonewater Housing in Weobley (read the case study here).

Typical Examples

Kensa’s Shared Ground Loop Arrays are suited to as few as two properties, although they are most common in medium to large scale projects (10+ dwellings).

Click the links below to learn more about these typical applications:

The RHI and SGLs

The ‘district’ nature of Shared Ground Loop Arrays qualify them to receive 20 years of guaranteed quarterly income via the Non Domestic Renewable Heat Incentive (RHI).

This guaranteed tax free income provides a return on investment, creating the opportunity for developers and property owners to confidently invest in Shared Ground Loop Arrays, or attract external funders to own the ground array and receive the RHI in return, thus lowering the upfront cost of the installation.

Non Domestic RHI payments for residential properties linked to shared ground loops are paid on the deemed heat consumption taken from the property’s Energy Performance Certificate.  This arrangement mirrors previous policy for stand-alone ground source heat pump installations supported by the Domestic RHI, and gives certainty to the owner of the ground array and recipient of the RHI income.

Finance Options

Self Financed SGLs

With a guaranteed 20 year income stream via the Non Domestic RHI, self-financing Shared Ground Loop Arrays are a great option if capital is available to cover the entire project installation costs.

The property owner owns the entire system; the heat pumps, internal heating distribution system, and the external pipework and ground arrays.

Read more

Funded SGLs (Split Ownership)

Kensa has developed an innovative funding and delivery model via Kensa Utilities, where the cost of the Shared Ground Loop Array is no longer borne by the house builder or owner.

Kensa will design, supply, install and own the shared ground loop array; in return Kensa will receive an income via the Non Domestic RHI, plus a connection charge to the house purchasers (equivalent to the gas standing charge).

The heat pumps and internal heating distribution system will remain the property of the property owner.

Read more

Related Content


Split ownership of Shared Ground Loop Arrays (SGLAs) unlocks funding mechanisms to encourage the wide scale adoption of ground source heat pumps at zero-cost to the client. Kensa Utilities provides access to such funding mechanisms and investors.


Frequently Asked Questions (FAQs) about Kensa Shared Ground Loop Arrays (SGLAs) Got a question about shared ground loop arrays? Read through some of the most common questions below. If you cannot find an answer to your question please contact us on 0845 680 4328 or send us your project details for a bespoke quote.

Videos: Shared Ground Loop Array Ground Source Heat Pumps In Tower Blocks

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.

Blog: Greater London Authority Heat Pumps Report: Kensa’s Review

Summary: The Greater London Authority (GLA) has published a report into the scope and opportunity for ‘Low Carbon Heat: Heat Pumps in London’. The report compares various air source, direct electric, gas and CHP configurations in new build houses, and concludes that shared ground loop arrays are the most efficient, lowest carbon, and lowest cost solution. Kensa’s…

Blog: Cutting The Capital Costs Of Carbon Compliance

Summary: Cost to comply with emissions reduction targets to increase for developers who traditionally specified gas, in particular gas CHP, and decrease for those specifying shared ground loop array ground source heat pumps. GLA heat pumps report identifies shared ground loop arrays with individual ground source heat pumps as the lowest carbon & lowest cost…

News: England’s Largest District Ground Source System Breaks New Ground

The UK’s pioneer of domestic district ground source heat pump systems, Kensa Contracting, has secured the contract to deliver England’s largest shared ground loop array heat pump system with ENGIE.

Blog: How GSHPs Overcome Overheating & Provide Passive Cooling

Summary: Summers are getting hotter – 2018 was one of the hottest ever recorded. Extreme heat is responsible for record numbers of emergency hospital admissions. Royal College of General Practitioners (RCGP) to cease investment in all fossil fuel companies as part of a drive to combat climate change and hotter summers and lower air pollution…

Blog: Quit The Habit: Improve Health & Air Pollution By Switching to GSHP

Summary: Public health charity Medact say air pollution is “comparable to tobacco in terms of the number of deaths per year for which it is responsible”. Outdoor air pollution contributes to around 40,000 premature deaths, over 6 million sick days and an estimated total social cost of over £20 billion per year. 44 of the 51 UK…

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