抄録
Achieving carbon neutrality by 2050 requires the decarbonization of existing buildings and the enhancement of flexibility to support demand response. While various demonstrations utilizing Distributed Energy Resources (DERs) have been conducted, there are limited cases focusing on retrofitting electric vehicles (EVs) into existing buildings. The purpose of this study is to propose and evaluate a retrofittable EV-DER (Electric Vehicle–Distributed Energy Resource) system that enables decarbonization of existing buildings. We installed a bidirectional charger-based system in an existing office building and measured its charge–discharge efficiency. We estimated its decarbonization impact via numerical simulation. Simulation results show that the system can reduce building-related CO₂ emissions, with demand response using bidirectional chargers. However, as EV driving distance increases, CO₂ reduction from decreased gasoline usage grows, while the DR-based reduction diminishes. In market-price-linked DR strategies, charging tends to occur at night and discharging in the morning, which may result in higher CO₂ emissions than charging from surplus photovoltaic (PV) power. These results show the potential of EV-DER system operations and integrating renewable energy sources to enhance the overall decarbonization effect of the systems in retrofitted buildings.
