Long-term climate-dependent performance and cost-benefit analysis of façade-integrated low-concentration photovoltaic systems

Evaluating the performance and economic feasibility of façade-integrated asymmetric compound parabolic concentrating photovoltaic (ACPC-PV) systems across different climatic regions is important for their practical deployment. In this study, a three-dimensional optical model is established to evaluate the optical performance of ACPC-PV. Based on long-term meteorological data, the annual energy yield and economic performance of façade-integrated ACPC-PV are compared with those of façade flat PV across different climatic regions. Key parameters considered in this study include installation angles, solar altitude and azimuth angles, climatic conditions, and reference economic parameters. The results indicate that a reference installation angle for façade ACPC-PV is determined to be 30° in regions between 20° and 45° N. The annual solar energy harvested by ACPC-PV at 30° can be up to 115% higher than that at 0°. ACPC-PV installed in cities between 30° N and 40° N demonstrates superior annual performance compared to flat PV, with a maximum annual energy gain of 52%. Based on the reference energy demand and electricity price, the shortest and longest payback periods of façade ACPC-PV are 7.5 and 11.8 years in Lhasa and Chongqing, respectively. In terms of cost-effectiveness, façade ACPC-PV installed in regions with scarce solar resources offers the greatest advantage compared to flat PV, and the maximum reduction of payback period is 21%. These findings provide quantitative guidance for identifying suitable installation configurations and climatic regions for early-stage assessment of façade-integrated ACPC-PV systems.