Decarbonising heating and cooling using temperature setback and geothermal energy

The lion’s share of buildings’ energy consumption is used for maintaining a thermally comfortable indoor environment. Strategies of reducing heating and cooling demand can thus be crucial for buildings to achieve net zero. This research aims to investigate the extent to which an occupancy-based temperature setback strategy and geothermal energy supply can decarbonise an office building. The objectives include: 1) exploring the optimal setback temperature for maximum energy savings, both in present time and under the future climate scenarios, and 2) evaluating the extent to which a geothermal borehole can meet the building’s energy demand. The outcome shows that a temperature setback strategy coupled with geothermal energy supply can decarbonise heating and cooling by around half. As for overall building energy demand, temperature setback can make demand reduction by over a tenth while the geothermal energy can meet the demand by a minimum of a fifth.