Optimization of a combined heat pump/storage system with solar or convective heat collectors

Other conference contribution, 1985

A large computer program simulating space heating systems in large multifamily houses or small district heating systems is presented. The system consists of a heat collector, either an ambient-air natural convective collector or a solar collector, a heat storage with vertical pipes in the ground, and an electrically driven heat pump. The most important technical and economical design parameters are the size of the collector, the storage, the heat pump, and the system control. The influence of these parameters on the annual COP and the heat supply ratio has been simulated and is discussed. This influence is presented in a generalized way. With the aid of the technical results an economic optimization is made of the system. The optimum is flat but sensitive to the combination of the system parts. A sensitivity analysis on the optimum is made to show the influence of investment and energy costs. Finally the system is compared with a heat pump without storage which is found to be somewhat more economically advantageous.