16 September 2011
The optimal operation planning of energy supply systems to meet domestic hot water and electricity demands is analyzed, including CO2 heat pump systems, gas engine cogeneration systems, and polymer electrolyte membrane fuel cell (PEFC) co-generation systems. Projected demands were taken from data measured in the Kansai area in Japan,
over one year, with a sampling period of 30 minutes. The objective function of the optimization is the minimization of primary energy consumption. The optimal operation of the PEFC and gas engine based co-generation systems, and that of the CO2 heat pump system
are compared with that of a reference system consisting of a condensing gas boiler and grid electricity. The primary energy consumption ratios and CO2 emission ratios between the systems and the reference system are compared. The results show that the CO2 heat pump system is superior to the other co-generation systems in minimizing both primary energy
consumption and CO2 emissions.