Economic Viability of Photovoltaic Systems Based on the Number of Floors in Modular Multi-Family Housing in Korea

Korea is making efforts to reduce carbon emissions from buildings and, as part of this initiative, the government is promoting the expansion of modular housing. This study analyzed the feasibility of achieving zero-energy certification and the economic viability of applying photovoltaic (PV) systems to modular housing in Korea. Energy consumption and self-sufficiency were calculated for low-rise (4 floors), mid-rise (13 floors), and high-rise (30 floors) buildings. Economic viability was assessed according to the payback period, net present value (NPV), and benefit–cost ratio (B/C ratio). Construction costs of modular buildings are higher than those of reinforced concrete (RC) buildings, and when only PV systems are applied, it is not possible to achieve a high grade in high-rise buildings. The results indicate that economic feasibility is lacking across all building heights, leading to the conclusion that further research on cost reduction and expanded government support are necessary. This study presents a sustainable building model for Korea that is expected to contribute to future policy decisions.