OPTIMAL SIZING OF A HEAT-PUMP THERMAL STORAGE-SYSTEM BASED ON THE LINEAR-PROGRAMMING METHOD

An optimal planning method is proposed for a heat pump/thermal storage system that utilizes time-of-use pricing of the electrical utility. E quipment capacities are determined so as to minimize the annual total cost in consideration of system's operational strategies for energy de mand requirements. This optimal planning problem is solved by the line ar programming method. Through a numerical study on a heat pump/therma l storage system for a commercial building, the effect of thermal stor age tank is investigated on the long-term economics of the system. A p arametric study is also performed with respect to the initial capital unit cost of thermal storage tank. The relation is clarified among the optimal capacities of thermal storage tank and other pieces of equipm ent. It is ascertained that this optimal planning method is a useful t ool for evaluating the economic properties of heat pump/thermal storag e systems.