Scale-Dependent Degradation Kinetics and Reliability of Perovskite BIPV Modules under Semi-Arid Outdoor Conditions

Perovskite photovoltaics are promising candidates for Building-Integrated Photovoltaic (BIPV) applications, but their long-term outdoor stability is a critical challenge for large-scale deployment. This study investigates the degradation kinetics and reliability behavior of scale-dependent perovskite BIPV modules under the real-world semi-arid environmental conditions in Peshawar, Pakistan. Two perovskite modules of active area 300 cm² (Module A) and 500 cm² (Module B) were monitored separately from October 2025 to January 2026 with an IoT enabled data acquisition system integrating INA219 sensors, ESP32 based monitoring and environmental sensing devices. We investigated the electrical performance, energy yield, conversion efficiency, degradation characteristics and reliability metrics at various irradiance, temperature and humidity conditions. The results indicate a progressive degradation for both modules, with a significantly higher performance deterioration for Module A (smaller area). The conversion efficiency of Module A decreased from 4.40% to 2.29% (loss of 47.9%), while the loss of Module B was comparatively smaller from 7.23% to 6.11% (loss of 15.5%). Module B contributed >70% of the total energy yield and 84.5% of the initial efficiency, while only 52.1% of the initial efficiency was retained for Module A. The efficiency decay behavior was well described by first-order degradation kinetics with degradation constants of 0.218/month and 0.056/month for Module A and B, respectively, indicating that the degradation rate of Module A was about 3.9 times faster. Reliability tests also showed increased stability of the larger module after prolonged outdoor exposure. Our findings provide direct evidence of the scale-dependent degradation and reliability performance of perovskite BIPV systems and highlight the enhanced resilience of larger-area modules for long-term utilization in semi-arid climatic environments.The results show that module size plays an important role in the outdoor stability of perovskite BIPV devices, where larger area modules are more resistant to environmental degradation for semi-arid climate conditions. This study provides one of the first climate-specific evaluation of scale-dependent perovskite BIPV degradation in Pakistan and useful insights for design, deployment and long-term optimization of perovskite-based building-integrated photovoltaic technologies.