AT-19-C030 -- Experimental and Simulation Studies on Solar-Ground Source Heat Pump System

We developed a high-efficiency water source heat pump system which utilizes multiple heat sources. As main components of the system, a Sky Source HeatPump, SSHP, utilizing solar heat and air heat, and a large-diameter ground heat exchanger with thermal storage capacity of the internal water weredeveloped. The system can be efficiently operated by utilizing solar heat at daytime and ground heat at nighttime. Also surplus heat from the solar heatcan be stored in the ground heat exchanger. We had conducted an experiment of the whole system and confirmed its performance in heating operation.According to the evaluation of two experimental days, the results showed that the SSHP and whole system have COPs of 9.3 and 3.1, respectively.Furthermore, a system simulation including the models of above two components was developed. As a result of comparative verification between theexperimental data and simulation data, it was confirmed that the simulation had sufficient accuracy. Then, the annual performance of the whole systemwas predicted by the simulation and the results showed that the SSHP and whole system have high annual COPs of 7.5 and 4.2, respectively.