Μake us preferred on Google Solar panels on Athens’s rooftops could generate as much as 1.8 terawatt-hours (TWh) of electricity a year, meeting a significant share of the energy needs of households and businesses. The figure comes from a scientific study, with researchers from the National Observatory of Athens among the authors, that examines how much electricity rooftop photovoltaic installations could produce across the 27 capitals of the European Union.
In Athens, the study estimates that about 24.5 square kilometers of rooftop space is suitable for solar panels, with a potential annual output of roughly 1.8 TWh. That would avoid an estimated 512,000 metric tons of carbon dioxide equivalent each year and could bring in about 117.39 euros million in annual revenue.
Paris shows the highest potential output of any capital in the study, at around 3.81 TWh a year, followed by Berlin and Budapest at about 2.55 TWh each. Across all 27 capitals, estimated annual generating potential ranges from 0.2 to 3.8 TWh. In the best-performing cities, rooftop solar could cover about 35% of total electricity demand.
The study also finds that avoided carbon dioxide emissions could reach roughly 1 million metric tons of CO2 equivalent a year in some cities.
The research was published in the international journal Energy. It sets out a single framework for assessing rooftop solar potential in all 27 EU capitals. The authors drew on atmospheric data from 2008 to 2023, satellite information from the Copernicus services and data on urban building layouts, and they modeled solar output with the PVGIS tool.
The analysis accounts for three factors that reduce the sunlight reaching the panels, and with it the electricity they produce. These are cloud cover, aerosols in the atmosphere, and shading from neighboring buildings and other features of the urban landscape.
