Abstract
This study theoretically examines primary energy saving by cogeneration in relation to three alternative energy supply models : steam boiler with steam-driven chiller, electric heat pump and gas/oil-driven heat pump. Using energy flow tables of five different operational patterns of cogeneration and alternative models, primary energy saving ratio was formulated, calculated and put into charts in relation to heat/electricity consumption ratio. Following results were obtained : (1) Cogeneration with engine or fuel cell can claim substantial energy saving even against heat pump with high COP where heat/electricity consumption ratio is less than 1.5. (2) Energy saving is retained even under partial-load operation.
