TownRock Energy (TRE) was commissioned by NHS Grampian to deliver a first-of-its-kind feasibility study investigating the viability of three deep geothermal energy technologies to meet the heating demand of the Foresterhill Health Campus in Aberdeen. These technologies were:

  1. Coaxial Geothermal Systems
  2. Advanced Closed-loop Geothermal Systems (AGS)
  3. Engineered or Enhanced Geothermal Systems (EGS)

Foresterhill lies atop the Aberdeen Granite, a formation naturally enriched in radiogenic elements, resulting in elevated heat production. This, combined with the substantial heat demand of the hospital (and wider area), makes it a strong candidate for a deep geothermal project.

Working under a tight 3-month deadline to meet NHS year-end requirements, TRE delivered a comprehensive study that concluded that EGS was the optimal solution for meeting the large multi-megawatt heating demand.

The study comprised several key components:

  • A geological assessment of the Aberdeen granite to forecast its depth and lateral extent, and the predicted geothermal gradient underneath Foresterhill.
  • A heat demand assessment, using client gas consumption data to generate heat demand curves and calculate peak, baseload and average heat demands.
  • Reservoir modelling using CMG STARS software to simulate each technology at various depths and optimise their design.
  • Comprehensive commentary on TRE’s recommendations, including an EGS concept design and a proposal for an exploration drilling program to calibrate the geothermal gradient at depth. A delivery timeline was predicted for each phase.
  • Costing of all options based on TRE’s supply chain and extensive industry network.
  • Techno-economic modelling comparing EGS to a business-as-usual (gas) scenario and a counterfactual, with the calculation of a levelized cost of heat to enable direct comparison between the options.

The success of the findings led to a second, higher-level screening work package, which explored the potential for other NHS Grampian sites in northeast Scotland to adopt geothermal technologies to meet their heating demands.

Following the completion of the study, TRE has remained actively engaged with the client, providing ongoing support as they progress to the next stage of the process to pursue grant funding options.