A review on BIPV-induced temperature effects on urban heat islands

Urban Heat Islands (UHI) occur in and around cities, leading to warmer temperatures than in surrounding rural areas. The UHI effect increases energy demand, air pollution levels, and heat-related illness and mortality. Solar energy is one of the most widely adopted renewable energy generation technologies in the built environment. Solar photovoltaic (PV) systems, integrated into building envelopes, can form a cohesive design, construction and energy solution for buildings, namely, building-integrated photovoltaic system (BIPV). However, the BIPV panels might potentially exacerbate the UHI intensity by trapping more heat in urban areas. This review paper uses a detailed literature survey of over 100 sources to evaluate whether the uptake of BIPV systems in urban areas contributes to an aggravation of the UHI effect. The survey found both direct and indirect impacts of BIPV systems on UHI, which also identified the fundamental causes of UHI such as the albedo effect and heat dispersion and how this would be embodied in the BIPV installations. Furthermore, this paper discusses how to mitigate the impact of BIPV systems on the UHI, as well as the future research directions around this concern in relation to the urban design.