Favourability index: an early-stage geospatial screening tool for low-enthalpy geothermal assessment mapping in superficial aquifers

This paper facilitates heating-decarbonization policy implementation with regards to district-scale ground source heat pumps (GSHPs), demonstrating how favourability tools and geospatial visualization can inform communities’ and policy-makers’ net-zero decision-making. A map-based decision tool visualizes the geospatial relationships between heat resource, heat demand and socio-demographic consideration factors. A framework of six core geological and heat demand considerations is presented with additional socio-demographic data integration by the end user encouraged. An underpinning algorithm combines data, creating a resource favourability index, weighting of which is user defined. Capacity to dynamically integrate, visualize and manipulate intrinsic and external data enables informed policy decisions and system design. End users may direct specific geospatial queries combining all data types, allowing a non-geological expert, policy-maker or community organization to form a holistic understanding of the limitations and benefits to GSHP deployment. Initial findings in Scotland indicate that superficial deposit distribution primarily drives the geothermal resource extent; however, the heat demand distribution is a major spatial limitation to utilization. A key policy implication is the nature of the localized resource, which requires local knowledge and planning to utilize. Responsibility for realizing national carbon targets through such energy planning measures increasingly lies with local governments, to which this tool contributes a method of geoscience-to-policy communication.