This web app uses the Google Maps API and PV Watts to estimate the surface area of a roof (or land) and how much solar radiation it receives in the course of a full year. This data is then used to price the roof (or land) so the home owner can lease the it to solar installers to put solar panels on it.
1- This can be very useful to home owners who do not want to go solar but they still want to monetize their roof.
2- Companies who need good sites to produce solar energy.
The first version of this was built in th San Francisco Angelhack Hackathon 2015.