Mapping the planet’s solar potential, one roof at a time

In 2015, Google launched Project Sunroof, an online tool based on Google Earth’s 3D imagery that helps individual homeowners explore whether they should go solar by analyzing everything from high-resolution aerial mapping and 3D modeling of residential roofs to sun positions, historical weather patterns, shadows cast by nearby objects, and typical electricity consumption. From all these calculations, Sunroof produces a home summary estimating how much power a given home could generate with solar, and how much that home might save in electricity costs. In addition, in November 2016 we launched a new data explorer tool to enable solar viability reports to be run at the state, county, city, and zip code levels. This new feature aims to provide a source of information for community members, researchers, and policymakers to help them make the case for solar deployment at a much larger scale. Currently, Sunroof is available in 42 states and has mapped over 43 million rooftops. More than 2 million users have accessed the tool to make informed decisions about solar.