Monitoring a Ground Source Heat Pump System in the Mediterranean climate of Cyprus
Date Issued
2024
Abstract
European Union (EU) has developed energy strategies and has invested in new energy technologies to ensure higher energy efficiency of buildings. The Ground Source Heat Pump (GSHP) system is one of the most well-known geothermal systems and renewable energy technologies for heating and cooling of buildings due to its high efficiency (see Coefficient of Performance – COP) and its environmental friendliness. GSHPs make use of Ground Heat Exchangers (GHEs), which are designed to cover the energy demand both in summer and winter. Such geothermal systems can be controlled by a remote monitoring system (building management systems – BMS). In this study the evaluation of a GSHP/GHE system performance regarding the use for heating and cooling in the building where the University Municipal Library of Limassol (Cyprus) is housed. The system (GSHP controlled by the BMS) acts as a research and educational laboratory. The GSHP system includes vertical GHEs with various specifications and two open loop (well) systems. A theoretical and experimental investigation is needed to evaluate the performance of the different parts of the geothermal system and give recommendations for improving its efficiency. The entire GHE system is constantly monitored by a digital program that records the energy, flow, volume, incoming and outgoing temperature at each installed HP. The general three-dimensional convection-diffusion equation is used to model the individual GHEs. In addition, based on data collected for several summer and winter months, (i) the electrical power into the system, (ii) the power absorbed /rejected by/to the system, and (iii) the COP of the whole system (including all installed GHEs) are estimated and compared. By studying the obtained results, several suggestions regarding the operation and the optimization of the GSHP as well as the BMS systems will be discussed.