The tool, which uses Google Earth’s high-resolution aerial mapping technology, launched in August and has now expanded to several more states. Metro areas in California, North Carolina, Nevada, Massachusetts, Arizona, New Jersey, New York, Connecticut, and Colorado are now covered by the service. Most of these states made the Solar Energies Industry Association’s list of the Top 10 Solar States in 2014.
When residents in these states enter their addresses into the tool, it uses data to figure out “how much sunlight your roof gets, the orientation, shade from trees and nearby buildings, and local weather patterns — essentially creating a solar score for every rooftop that it maps,” Carl Elkin, the engineering lead for the project, writes in a blog about the expansion.
I tried it out with my cousin’s address in Phoenix. She gets 2,133 hours of usable sunlight per year (since often-rainy Oregon isn’t covered by the tool, I’ll just have to assume that’s more than Portland), which makes her seem like a good candidate for solar.
The tool also shows how much money she’ll save, depending on whether she leases or buys the panels, or if she takes out a loan to cover the cost. Putting up the estimated $11,000 (after incentives) will end up saving her about $11,000 over 20 years. Leasing will only save her $1,000 over the same time period, though she wouldn’t have to pay anything up front. Of course, for a lot of people, the benefits of going solar aren’t all about the savings.
