Decarbonization Methods for Detached Houses Considering Dynamic Co₂ Emission Factor

This study investigates decarbonization strategies for existing detached houses using simulations with dynamic CO2 emission factors. A standard house model compared CO2 emissions under four measures: insulation retrofits, equipment upgrades, shifting appliance operation times, and installation of photovoltaic (PV) systems and batteries (BT). Results showed reductions of 14%, 22%, and about 30%, respectively, for partial insulation, full insulation, and equipment upgrades. Daytime operation of heat pump water heaters further reduced emissions, while PV and BT achieved reductions up to 62%. Future PV penetration may enhance CO2 reduction by promoting daytime operation of appliances such as heat pump water heaters.