Solar energy potential assessment on urban rooftops using digital surface models

Rooftop solar photovoltaic (PV) systems have the advantage of producing electricity without air pollution and greenhouse gas emissions, at the same time reducing carbon footprint as well as urban heat island effect. This study aims to assess physical, geographical and economic levels of solar energy potentials in actual atmospheric conditions on urban rooftops, using two municipalities in Athens, Greece as an example. 

We utilize very high-resolution digital surface models for the computation of clear-sky solar irradiance considering surrounding shadows. For all-sky conditions, cloud and aerosol data from 2012 to 2021 are obtained from the Copernicus Atmosphere Monitoring Service radiation service and the ECMWF Atmospheric Composition Reanalysis 4 product, respectively. The goals are to quantify the effect of solar elevation, the shadowing effect from adjacent buildings and constructions, and the effects of clouds and aerosols on the solar radiation availability on the rooftops and to investigate their interconnections. The spatio-temporal resolution of the analyses ranges from individual rooftop to neighborhood scale (approximately 3000 buildings) and from hourly intervals to ten years periods.

The results of the solar potential assessment are made available as a web GIS map for potential public access, intended to aid urban planning and encourage widespread adoption of solar energy in the public and private sectors.