Using earth as a natural energy source, ground-source heat pumps (GHPs) are increasingly gaining in popularity, offering lower energy costs and decreasing greenhouse gas emissions. Such systems typically employ a heat exchanger in contact with the ground or groundwater to extract or dissipate heat. Vertical GHPs are amongst the most popular. Scientists initiated the EU-funded project ECO-GHP (Multi-criteria assessment and optimization of geothermal heat pump systems) to successfully scale GHP technology from individual homes to larger buildings. Innovative computer-based assessment and optimisation methodologies enable designing the optimal configuration of multiple GHPs. The methodology approach includes evaluations of life-cycle assessment of different GHP configurations and techno-economic criteria. Employing linear programming methods and evolutionary algorithms combined with numerical and analytical computing, scientists studied various hypothetical and realistic scenarios. These involved existence or absence of groundwater flow, as well as homogeneous and heterogeneous hydrogeological conditions. In addition, they inspected GHP fields of different sizes, with seasonally variable heating and cooling energy demands. The team found that the optimal GHP configuration was on field edges instead of being installed in lattice frameworks, thus enhancing lateral conductive heat provision. Simulations confirmed improvement over conventional practice. ECO-GHP introduced a robust methodology that can be applied to various geological conditions for planning and operating multiple GHPs. Properly designed and installed, these systems offer an attractive alternative to fossil fuel-based space heating.
Geothermal energy, large buildings, ground-source heat pumps, heat exchanger, heating and cooling