ScholarWorks@중앙대학교

초록

This study evaluates the energy performance, operational carbon emissions, and energy autonomy of electrified residential buildings compared to a conventional gas-based Zero-Energy Building (ZEB) under Korea's ZEB certification framework. A detached single-family house was modeled with three configurations: a gas-based ZEB, a Packaged-Terminal Heat Pump (PTHP) ZEB, and an Air-to-Water Heat Pump (AWHP) ZEB. A 3-kW rooftop photovoltaic (PV) system was applied to all cases, representing a typical residential-scale installation for energy self-sufficiency. The results show that full electrification increases primary energy consumption-from 148.3 to 201.6 kWh/m2<middle dot>yr-under the current source energy conversion factor (2.75 for electricity), making it difficult for electrified ZEBs to satisfy the present 90 kWh/m2<middle dot>yr threshold. Although the electricity emission factor (EF) of the Korean grid is projected to decline significantly from 0.4781 to 0.0480 kgCO(2)eq/MWh by 2050, this reduction reflects grid decarbonization, not changes in building performance. When building operational emissions are recalculated using the future EF values, electrified ZEBs show substantially lower annual emissions than the gas-based case, highlighting the long-term benefits of electrification under a decarbonized power system. PV-based energy autonomy analysis reveals that the load cover ratio (LCR) and self-consumption ratio (SC) remain within 38-67%, while the self-sufficiency ratio (SS) exceeds the 20% threshold required for ZEB certification. Nevertheless, the high loss of power supply probability (63-78%) underscores the necessity of storage or load-shifting strategies. Overall, electrification represents a viable transition pathway toward carbon-neutral ZEBs, contingent upon continued grid decarbonization and expanded renewable integration.

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