Project Sunroof is a new tool from Google which allows homeowners to explore easily whether or not they would benefit from solar panels. To start, the tool will be available in select regions, and will allow homeowners to put their address in, and see the projected cost savings from going solar. Google explains it as:
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.
To crunch the numbers, Project Sunroof will calculate how much light hits your rooftop throughout the year, then factor in roof orientation, trees, nearby buildings and more. You can then enter your typical electric bill, and the tool will combine all of the data to show your projected savings, as well as help connect you with local installers. If you are not in one of the initial pilot regions, you can sign up to be notified when Project Sunroof is available in your area.
Source: Google Green Blog