16 September 2011
This study was conducted to research characteristics and merits of gas engine
driven heat pump (GHP) as heating equipments for cold climate. While its cooling cycle is just the same as electric heat pump (EHP), its heating cycle is quiet unique. GHP utilizes not
only aerothermal heat from ambient air but also waste heat from gas engine, resulting in high performance at low ambient temperature. From technical data, EHP for cold climate cannot
keep its capacity at low ambient temperature even though it uses the special systems such as liquid injection and two stage compression. However, GHP maintains its capacity due to
utilization of waste heat. About 20,000 units have been installed so far in Hokkaido which is as cold as major metropolitan cities in high latitude such as Stockholm, Helsinki, Moscow
and Chicago, where outdoor temperature reaches less than -20 degree of Celsius. Even in Hokkaido, GHP is used with good performance without any back-up heaters. GHP has a
possibility to be a suitable heating system in most of the cold region throughout the world.