Unveiling the impact of Urban Heat Island (UHI) effect on photovoltaic panel efficiency: A case study in Mashhad, Iran

The deployment of photovoltaic (PV) systems in urban environments is a key strategy for achieving sustainable energy goals and reducing carbon emissions. With rapidly growing urban populations, cities face the compounded challenge of the Urban Heat Island (UHI) effect, which raises ambient temperatures and increases building energy demand. Elevated temperatures in urban areas not only impact human comfort but also significantly reduce PV panel efficiency, limiting the potential of solar energy as a clean and sustainable source. Despite extensive research on UHI and PV performance individually, few studies have quantified the combined impact of UHI on PV energy production at the scale of residential buildings, particularly in cold and semi-arid climates. Motivated by this research gap, this study developed a novel, simulation-based methodology that integrates UHI-modified weather datasets with detailed building and PV performance modeling. A representative five-story apartment in Mashhad, Iran—a rapidly growing urban center with unique climatic and urban characteristics—was analyzed under both rural and UHI-modified climatic scenarios using the Urban Weather Generator (through Dragonfly) and validated Honeybee and Ladybug plugins. The results indicated that an average annual UHI-induced temperature increase of 2.01°C reduced PV electricity generation by 162.4 kWh per year for a typical residential unit. This research introduces a comprehensive methodology that couples dynamic urban climate simulation with detailed building and PV performance modeling, providing a more accurate assessment of renewable energy potentials in cities affected by UHI. The findings offer actionable insights that can guide urban planners, designers, and policymakers in integrating UHI mitigation strategies into PV deployment frameworks to optimize renewable energy production and enhance the overall climate resilience of urban areas. • Pioneering quantification of PV energy yield losses driven by Urban Heat Island (UHI)-induced temperature rise. • Comprehensive analysis of PV panel thermal performance degradation under UHI conditions. • First simulation-based assessment of UHI impacts on PV systems in Mashhad’s cold and dry climatic context. • Development of a customized PV system for a representative residential building typology in Mashhad. • Integrated simulation of building energy consumption and PV production using advanced parametric modeling tools.