ICLEI Europe in collaboration with the municipality of Madrid, used Google‘s Environmental Insights Explorer (EIE) to explore solar development objectives and insights into the city‘s rooftop PV capacity and energy generation potential. As stated in the “Madrid 360 Solar” strategy of the city, 30% of the electricity demand of municipal buildings should be covered by rooftop solar panels by 2030. High-quality data is critical for cities to evaluate the viability of their goals and set new ambitious objectives. This case study explores how Google’s EIE can support cities’ solar rooftop energy strategies.