TO-82-08-4 -- An Optimized Two-Capacity Advanced Electric Heat Pump PDF

A two-capacity residential electric heat pump, utilizing a unique dual-stroke compressor, has been developed, designed, constructed in preprototype form, and laboratory tested. The estimated annual energy-efficiency of this system is 20 percent better than the presently available two-speed electric heat pump. A computer-based constrained optimization procedure was used to select heat exchanger proportions, airflow rates, and compressor stroke ratio in order to minimize the annual ownership cost subject to comfort constraints upon delivered air temperature and dehumidification. A high-efficiency dual-stroke compressor, indoor blower and outdoor fan, plus a microprocessor-based control system were specifically developed for this system. This paper highlights the hardware development and summarizes system and component performance.