To achieve a sustainable society, it is important to reduce greenhouse gas (GHG) emissions, which are the main cause of climate change. As a measure to reduce GHG emissions in the automotive industry, the transition to battery electric vehicles (BEVs), which do not emit GHGs while driving, is considered to be effective. However, considering the entire life cycle, they do emit GHGs, and it is unclear to what extent they can actually contribute to climate change countermeasures. Therefore, the importance of life cycle assessment (LCA) for BEVs in the automotive industry is increasing. This study aims to evaluate the environmental impact by conducting a detailed LCA of BEV parts from the resource extraction to the product manufacturing phase. This paper evaluates five driving units: drive motor, power delivery modules (PDM), inverter, high-voltage cables, and air conditioner (AC) compressor. The environmental impact was evaluated by CO2 equivalent. To obtain the activity data necessary for the calculation, the authors disassembled the BEV units and identified the weight, materials, and manufacturing processes of the components. This analysis confirmed that GHG emissions from copper were commonly high in the driving units. Furthermore, a comparison of AC compressors for BEV and internal combustion engine vehicle (ICEV) showed that the GHG emissions for the BEV version were 1.6 times higher due to the difference in power source.
Nagai et al. (Wed,) studied this question.