Google's stated mission is to "organize the world’s information and make it universally accessible and useful". At first this mostly meant cataloguing and ranking web pages for search, but for many years now Google has ventured into the physical world with projects like Google Maps and Google Books. The latest project to come out of the Mountain View company is Project Sunroof, a website that aims to make it easier for homeowners to figure out if they should go solar, and if so, what the costs and benefits will be.
Project Sunroof takes a similar approach to what other solar installers have been doing by using aerial imagery combined with clever software to give a pretty good estimate of how much solar radiation is falling on a particular roof, how big a solar array you would need to generate as close to possible to 100% of your needs, and how much clean power would be produced on an average year based on multiple factors, which then feeds into financial calculations based on local electricity rates.
Here's some of what goes into figuring out how ideal your roof is for solar power:
Project Sunroof computes how much sunlight hits your roof in a year. It takes into account:
Google's database of aerial imagery and maps
3D modeling of your roof Shadows cast by nearby structures and trees All possible sun positions over the course of a year Historical cloud and temperature patterns that might affect solar energy production
Google approaches it more as an aggregator, though, and at the end of the process they will refer you to solar installers that operate where you are (and no doubt get a referral fee for the service). It works a bit like these insurance or airline aggregators that will price-compare for you so you don't have to go to 10 different sites yourself. It's a useful service, and anything that makes going solar more convenient is bound to make some people who are on the fence jump in.
Project Sunroof just came out, so right now it only works for residents of the San Francisco Bay Area, Fresno, CA, and Boston, MA. But as they say in the video below, they have plans to expand it to the rest of the U.S., and maybe also to the rest of the world eventually.