Unlocking the superior potential of perovskite solar cells in urban built environments: A high-resolution numerical study in Tokyo

Abstract

Installing photovoltaics (PVs) on building surfaces is a promising strategy for decarbonizing cities. Although silicon-based solar cells (SSCs) dominate the market, perovskite solar cells (PSCs) have attracted increasing attention. However, their energy-yield potential on urban building surfaces remains poorly understood. Here, we quantified the city-scale energy-yield potential of PSCs on building surfaces, using SSCs as a reference with identical baseline efficiency, and identified ranges for their key operating conditions. To accurately capture urban thermal environments and localized weather, we developed an advanced framework integrating a coupled urban meteorological–building energy model with dynamic PV output models and applied it to Tokyo's 23 wards. Assuming identical baseline module efficiencies, PSCs increased annual energy yield by 15–39% relative to SSCs, depending on surface orientation. Their advantages were greatest on low-irradiance façades while also substantially increasing rooftop yields. Furthermore, PSCs generated the maximum additional electricity during summer, when urban cooling demand peaks, demonstrating robust performance across diverse irradiance levels. Crucially, our findings show that standard test conditions (STC) do not represent actual urban environments. We therefore suggest extending evaluation conditions for façade PVs to lower irradiance levels and wider temperature ranges. Meanwhile, we estimated the levelized cost of electricity (LCOE) for PSCs on building surfaces, demonstrating that PSCs on rooftops and south-facing walls can be economically competitive with at least one other renewable technology. Our findings provide insights into the potential role of PSCs in urban energy systems and contribute to the evaluation of next-generation PVs.