Evaluation of Geothermal Heat Pumps System for Energy-Efficient Heating in Norway

Abstract

The utilization of geothermal heat pump systems has emerged as a promising solution for sustainable and energy-efficient heating/ cooling in Norway. Norway, as the third-largest exporter of energy in the world and with an electricity supply dominated by hydropower, has benefitted from heat pumps to reduce electricity consumption peak loads and dependency on fossil fuels for energy production. This thesis aims to model a geothermal heat pump system, considering a single borehole within the Norwegian context. A comprehensive literature review is conducted, encompassing shallow and deep geothermal energy sources alongside various geothermal heat pump systems. The mathematical framework for heat transfer modeling in the wellbore is applied based on the infinite line source solution (ILS). To implement the mathematical model, phyton programming is applied. The effect of various factors governing heat transfer to the fluid, such as time, heat load, distance, soil thermal conductivity, geothermal gradient, inlet temperature, flow rate, and heat conductivity of wellbore/ grout material, is investigated. A sensitivity analysis is performed to investigate the impact of variations in key parameters on system performance. The technical and economic results indicate the vertical geothermal heat pump system, due to the higher temperature gradient and heat transfer area, can be an effective way to provide energy-efficient heating since power is produced from free and zero-emission source.