Economic and performance analysis of ground source heat pump system for high-rise residential buildings considering practical applications

Ground source heat pump (GSHP) systems are being applied in various buildings to achieve carbon neutrality and zero energy building. Large-scale residential buildings have seen limited use of GSHP systems due to the absence of design guidelines and established operation methods. While design guides for general buildings are available from associations or institutes, there is a scarcity of designs and operation guides that consider dynamic simulations with occupant conditions and detailed load conditions. Generally, it is crucial for the economic analysis to optimally design suitable system capacity and accurately predict the performance. Therefore, in this study, the dynamic energy simulation model was constructed by considering the condition of the occupants and system operation and quantitively analyzed economic feasibility and system performance. Furthermore, the sensitive analysis based on the practical range of operation was conducted for comparison with conventional systems, district heating (DH) and electric heat pump (EHP) system. The heat pump's performance improved by up to 12.6% based on GSHP system design factors. Although the initial investment cost of the GSHP system was 51.5–84.7% higher than DH and EHP systems, its annual operating cost was 20.8–33.1% lower. The ground source heat exchanger had the most significant impact on performance, while the thermal storage tank's capacity had the largest impact on annual operating costs, aligning with previous research findings. In terms of carbon emissions, the annual CO2 emissions of the GSHP system were 49.1% lower than those of the existing system. The study highlights that GSHP systems can achieve high performance, economic efficiency, and low CO2 emissions based on the design approach. Additionally, the study provides valuable insights into GSHP system design, offers quantitative feasibility data, and compares them to traditional heating and cooling systems, taking practical cost considerations into account. •Annual operation costs of GSHP system saved by 33% compared to DH and EHP system.•Performance of GSHP system improved by 13% as the GHEX length increased.•HST volume is the crucial design factor for annual operation costs of GSHP system.•GSHP system can be reduced CO2 emissions by 49% compared to DH and EHP system.