In an effort to help homeowners decide if making the switch to solar is an economically smart decision, Google yesterday unveiled its latest online tool called Project Sunroof. The website, essentially a layer over the search giant's popular Google Maps, uses satellite data to map a homeowner's roof, surrounding shade, and the number of hours of usable sunlight per year.

At first glance β€” particularly for those who've been following the solar industry β€” Sunroof might not look much different from past efforts. As of 2008, there were some seven websites that did something similar, including Sungevity and the popular RoofRay. While Sungevity has turned into a major installer in the solar industry, the company's mapping tool no longer exists. RoofRay, at one point the busiest solar website in the U.S., was sold off to a European investment group and has since disappeared.

project sunroofGoogle's Project Sunroof aims to give you an overview of how your home might take advantage of the sun. (Photo: Project Sunroof/Google)

As you might expect, Google's mapping tool is not only free (earlier efforts sometimes required registration), but also features polish and in-depth information that make its websites such a pleasure to use. For instance, in addition to quickly figuring out your savings based on your roof's estimated dimensions, you can also dig down and see numbers for upfront costs, estimated payback time, and even current state and federal incentives. It will then put you in touch with local installers to take the next big step.

Having access to this information is good news not only for the environment, but also for homeowners looking for new ways to save money on heating and cooling costs. The other big difference from 2008? Solar systems are more affordable than ever before β€” with a new study finding that the price of installed photovoltaic systems has fallen for a fifth consecutive year.

As the video mentions, Google is currently only rolling out Project Sunroof in the San Francisco Bay area and Fresno in California, plus greater Boston. It's also worth mentioning that the numbers provided are only estimates. As someone who recently installed a solar array on my own barn, I can attest that having an installer come out and more accurately gauge your sun/shade ratio will give you a much clearer picture of the upfront costs and potential savings/payback estimates.

solar barnAfter a solar installer came out to my property, it was determined that my barn roof offered greater exposure for solar than my home. (Photo: MdEstries)

Still curious about solar for your own home but bummed Project Sunroof isn't yet in your neck of the woods? A quick search online shows solar roof mapping tools for Washington, D.C., Cambridge, Massachusetts and New York City.