Google is mapping rooftops to find solar potential

Posted by Carl Elkin, Engineering Lead for Project Sunroof

Google announced its plans to determine the planet’s solar potential though what it calls “Project Sunroof.” Here is a piece published on the company’s Green Blog explaining the project. 

The cost of solar power is at a record low. A typical solar home can save hundreds or even thousands of dollars per year on their electricity bill. But, as a volunteer with the Boston-based solar program Solarize Massachusetts and a solar homeowner myself, I’ve always been surprised at how many people I encounter who think that “my roof isn’t sunny enough for solar,” or “solar is just too expensive.” Certainly many of them are missing out on a chance to save money and be green.

Enter Project Sunroof, my recent 20% project. Project Sunroof is a new online tool we’re testing to help homeowners explore whether they should go solar. Available in the San Francisco Bay Area, Fresno (in central California), and the Boston area for now, the tool uses high-resolution aerial mapping (the same used by Google Earth) to help you calculate your roof’s solar energy potential, without having to climb up any ladders.

If you’re in one of our test regions, simply enter your address and Project Sunroof will crunch the numbers. It first figures out how much sunlight hits your rooftop throughout the year, taking into account factors like roof orientation, shade from trees and nearby buildings, and local weather patterns. You can also enter your typical electric bill amount to customize the results. The tool then combines all this information to estimate the amount you could potentially save with solar panels, and it can help connect you with local solar providers.

Google has always been a big believer in zero-carbon energy, and solar power has been a central part of that vision — from accelerating the growth of rooftop solar, to helping finance the largest solar farm in Africa, to building one of America’s biggest campus solar arrays here in Mountain View. While Project Sunroof is in a pilot phase for now, during the coming months we’ll be exploring how to make the tool better and more widely available. If you find that your address isn’t covered by the tool yet, you can leave your email address and we’ll let you know when Project Sunroof is ready for your rooftop!