A potential CO2 reduction of vehicle to home system from life cycle perspective

A life cycle inventory analysis is conducted in this study to evaluate the environmental merit of a vehicle to home (V2H) system towards the conventional counterpart equivalent in terms of environmental impact category global warming expressed as CO2 emissions. The V2H system comprises a residential house, a photovoltaic solar system, a battery electric vehicle and a charging system, whereas the conventional system includes a residential house, a gasoline vehicle and a petrol station. The system boundary of each components consists of its production, use and end-of-life stages, where data available. CO2 emissions are calculated by applying the data of each components and life cycle stages collected from statistics and literature surveys to the Japanese life cycle inventory database. The emissions differ by the assumptions made; therefore a sensitivity analysis is also carried out to understand the potential variation of the CO2 emissions. The result indicates that about 35-42% CO2 reduction can be expected for a V2H system in comparison with the conventional system. Since the main contributors to CO2 emissions of both systems are dwelling, residential house construction, vehicle cycle and fuel cycle stages, these stages should be included in the system boundary of V2H system and it is important to select and design the appropriate components of these stages to assure the environmental merits of V2H system in terms of life cycle CO2 reduction.