Nest Road mine water geothermal system

The challenge

The system was designed by a previous consultant, so TownRock inherited a scheme with limited information about the original design. There was also no precedent to follow: no other comparable systems were operational in the UK at the time, which meant the technical, regulatory and maintenance problems all had to be solved for the first time.

What we did

TownRock Energy has developed and put into practice an operations and maintenance package and handbook, covering the responsibilities, regulatory requirements and operational procedures needed to run a mine water geothermal system cost-effectively and keep improving it. It includes optimisation of the heat distribution as well as borehole and plant room maintenance.

• Regulatory compliance. Technical monitoring and reporting to the relevant regulator and authority.
• Maintenance. Support and improvements that keep the system running sustainably over the long term.
• Management. Working with the heat pump specialist on a systems-thinking approach that balances the efficiency of the heat delivered against the geothermal resource.
• Education. Ongoing dissemination of best practice and learnings to the wider community, to further the geothermal sector in the UK.

What it delivers

The system has operated successfully since 2018 and delivers the full heating requirement of the warehouse with limited maintenance. It has a coefficient of performance of 4–5: for every unit of electricity used to power the heat pump, four to five units of heat are produced. Gas boilers, in contrast, have a coefficient of performance of less than 1. Investment payback is through the Renewable Heat Incentive, a discontinued UK Government scheme that benefits generators of renewable heat.

• Works alongside the neighbouring system at Abbotsford Road with no thermal interference.
• Lessons learned and knowledge sharing from Nest Road have contributed to the successful development of a new neighbouring mine water geothermal system owned and operated by Gateshead Council.