Abstract

Geothermal energy is an efficient low carbon solution for the heating and cooling of buildings. For many megacities, such as London, the amount of energy that can be stored in the urban local subsurface is greater than their annual heating and cooling demands. The ground source heat pump (GSHP) system, a shallow geothermal technology that provides heating and cooling for buildings by continuously replenishing the energy in the subsurface, has been used increasingly in recent years, but its application has been generally limited to single buildings. In this study, a GIS -based simulation model was developed to estimate how many GSH Ps could be installed at the city scale without losing control of the ground thermal capacity and to evaluate the degree to which such a system can contribute to the energy demands of the buildings in a city. The model was built by embedding a PYTHON -based GSHP design code into ArcGIS software and was trialled on the City of Westminster as a case study under the following two scenarios; (a) boreholes are ‘under buildings’ and (b) boreholes are ‘around buildings’. Under both scenarios, the model produced borehole allocation maps and ratio of capacity to demand maps. In addition, parametric studies have been conducted to analyse the influence of various factors on the ratio distribution.