Renfrewshire Tower Blocks Networked Heat Pump Retrofit
Project Background
Gallowhill and Glencairn Court are two 15-storey tower blocks in Paisley, Renfrewshire - a prominent part of the local authority’s decarbonisation plans to upgrade ageing heating systems for residents.
Each tower - in total 180 residences - has a significant and continuous heating demand, totalling 1,739,257 kWh per year across the estate. Kensa engaged Genius Energy Lab to assist in delivering the ground array design and technical modelling required for a full retrofit to ground source heat pumps (GSHPs) through a shared ground loop network. The aim being to deliver high-efficiency heat and hot water to each flat via individual Kensa Shoebox heat pumps.
This new low-carbon heating infrastructure - the largest networked GSHP system in Scotland and part funded by the Scottish Government's Heat Network Fund - is designed to support tower-block residents with reliable, affordable heating for decades to come.
A local authority first in the country, the scale of the heat pump system places Renfrewshire Council at the forefront of embracing clean heat technology to achieve long-term carbon reduction goals.
Our Role
Working within the constraints of a dense urban site, historic mining activity, and the need for minimal resident disruption, Genius Energy Lab worked with Kensa to design a robust, efficient ground collector system comprising:
- 80 vertical boreholes
- arranged as 8 arrays of 10–10 boreholes
- each borehole drilled to 172 metres depth
As Kensa’s design partner, Genius Energy Lab provided:
- Full ground array design and specification
- Thermal modelling
- Flow and load balancing across the shared ground loop network
- Support with securing appropriate permits from the Mining Remediation Authority in an area of historical coal mining
- Optimisation using the Genius Energy Lab’s proprietary technology
- Design assurance throughout drilling strategy development
This project demonstrates the advantages of early-stage design rigour in high-density retrofit environments where drilling optimisation, load distribution and geological risk together determine overall system performance.
Addressing Legacy Coal Mining Conditions
The Gallowhill and Glencairn Court site lies within an area of historic coal mining - a factor often, and incorrectly, assumed to be a blocker for vertical GSHP installations.
Genius Energy Lab supported Kensa in navigating the regulatory pathway with the Mining Remediation Authority, providing technical justification and borehole risk assessments required for approval.
The result? Vertical ground source systems are not only feasible in former mining areas, they can be an optimal choice when supported by detailed geological understanding and robust design.
What we delivered
Using Genius Energy Lab’s proprietary technology, the design team was able to significantly reduce the materials and energy required for drilling and installation, without compromising performance or longevity.
Total savings achieved
- 2,504 kWh drilling energy
- 189.20 m³ spoil
- 157.44 m³ grout
- 10,480 kg HDPE pipe
These optimisations also translated into major commercial benefits: with estimated drilling cost savings of over £275k.
For local authorities and housing providers working to tight budgets and decarbonisation timelines, savings of this scale materially improve the viability of GSHP retrofits.
