A high-resolution geospatial assessment of the rooftop solar photovoltaic potential in the European Union

Rooftop solar photovoltaic (PV) systems can make a significant contribution to Europe's energy transition. Realising this potential raises challenges at policy and electricity system planning level. To address this, the authors have developed a geospatially explicit methodology using up-to-date spatial information of the EU building stock to quantify the available rooftop area for PV systems. To do this, it combines satellite-based and statistical data sources with machine learning to provide a reliable assessment of the technical potential for rooftop PV electricity production with a spatial resolution of 100 m across the European Union (EU). It estimates the levelised cost of electricity (LCOE) using country-specific parameters and compares it to the latest household electricity prices. The results show that the EU rooftops could potentially produce 680 TWh of solar electricity annually (representing 24.4% of current electricity consumption), two thirds of which at a cost lower than the current residential tariffs. Country aggregated results illustrate existing barriers for cost-effective rooftop systems in countries with low electricity prices and high investment interest rates, as well as provide indications on how to address these. •An innovative method combines geospatial/statistical data to create raster of technical potential of solar rooftop in the EU.•Different datasets and sources are integrated to estimate the available rooftop area.•In many EU Member States, the levelised solar electricity can be produced at a lower cost than retail electricity prices.•Economic drivers (e.g. different weighted average cost of capital, retail electricity prices) outweigh technical factors.•Rooftop systems could cover up to 24.4% of the EU electricity consumption (based on 2016 levels).