A method to estimate the potential of rooftop photovoltaic power generation for a region

•Proposed a method to calculate PV potential by estimating the useful roof area and irradiance•Used city aerial photo data, manual selection, and pixel analysis to estimate the useful roof area•Selected 24 1 km2 samples of a city to estimate the useful roof area for PV systems•Estimated the total useful area for rooftop PV systems for a major city (Osaka, Japan)•Calculated the potential for rooftop PV to meet that city's electric demand

At present, solar energy is receiving heightened attention as a potentially widespread approach to sustainable energy production, and the study of photovoltaic (PV) technology has expanded globally. The amount of PV power generation is growing quickly. This paper proposed a method to calculate the rooftop PV potential for a city or region by estimating the total useful roof area for PV installations and incident annual solar radiation. The aerial photo data of a city and pixel analysis techniques with a C ++ program were used to estimate the rooftop PV potential of an example case, Osaka City, Japan in this study. The total useful area of PV system is estimated as 42,000,000 ± 9,000,000 m2 in Osaka. If the efficiency of PV power generation is assumed to be a value of 0.20 in this contribution, PV power generation could supply about 56% of the entire electrical power demand in the commercial sector, about 12,400,000 MWh/year, or could supply about 34% of the entire electrical power demand in the commercial and industrial sectors, about 20,300,000 MWh/year.