Economic analysis of a solar roof as an optional extra to electric vehicles in Korea: A case study

The solar roofs of electric vehicles (EVs) can generate electricity and provide various socioenvironmental benefits. However, the adoption of solar roofs is hampered by low practicality and utility to consumers. Therefore, this study explored the economic feasibility of EV solar roofs in Korea. Assuming a 20-year usage period for a solar roof with 204 W_p capacity, the current conditions of charging unit price (CUP) of 0.252 USD/kWh, and discount rate (DR) of 3.5 % in Korea were applied. The analysis showed an economic benefit in the present value of USD 687.87 and net present value of −312 USD, indicating it was not economically viable. However, sensitivity analysis revealed that a solar roof option will be feasible if both CUP increased and DR decreased satisfying conditions (e.g., 120 %&1.0 % or 140 %&2.5 %), respectively. A 10 % increase in CUP and a 1 % decrease in DR reduces the payback period (PBP) of the solar roof by approximately two years. Additionally, differences in the PBP were observed when using monthly capacity factor data instead of annual data. The underlying causes and potential solutions of the extended PBP were discussed. This study can provide primary information on the practical worth of solar roof options for rational consumer decision-making.