Sky view factor and sunshine factor of urban geometry for urban heat island and renewable energy

The sky view factor (SVF) and sunshine factor (SF) of urban geometry have been shown to be useful indicators of the urban heat island intensity(UHII). The SVF indicates the shielding from long and short-wave radiation gains and losses, significant in the urban heat island effect(UHI). The SF also shows the amount of direct solar irradiance that can penetrate a canyon. This paper shows how the SVF and the SF values can be calculated from the hemispherical image by a simple model. The study also shows that although the SVF and SF are useful indicators of the urban heat island and assess the UHII in Manchester, UK and in Ulsan, South Korea. This study demonstrates that the SVF and SF analysis using the fish-eye image is a useful and practical tool for any geographical locations and buildings.