Gas engine-driven heat pump systems
The “gas heat pump (GHP)” uses a natural gas-powered or LPG-powered engine to drive the compressor in a vapour-compression refrigeration cycle. The Japanese market for GHP air conditioners has been growing steadily since they were commercialised, with annual shipments of about 40 000 outdoor units in recent years. The major factors in their growth are power savings and low operating costs compared to “electric heat pump (EHP)” systems. This paper introduces the technology and market trends for the GHP in Japan.