An innovative project to promote alternative energy in San Francisco has resulted in the mapping of the city’s solar installations. The Google Maps mash-up allows users to find details on residential, commercial and municipal solar projects including the size and output as well as the expected electricity savings of each installation. The site also offers a potential solar energy calculator based on a particular address by analyzing the size of the roof and estimating the carbon savings if a solar system were to be installed.

The San Francisco Solar Map is an excellent example of how easy to use mash-ups can be help promote a cause. The aggregated information is a one-stop-shop for anyone interested or considering an alternative energy source such as solar. The ultimate goal would be to map all potential alternative energy sources, such as wind, solar and hydroelectric, and combine the data with existing projects that capture or harness these sources. This would allow people to identify the most cost effective way to reduce their reliance on the electricity grid in their area. Including things like federal and state level tax breaks would make the ROI calculation very easy. There is also potential for community collaboration around reaching a common goal – San Francisco’s plan is to install 10 000 solar roofs by 2012. A country-wide energy map would expose underutilized alternative energy resources and could become a platform for collaboration around and co-ordination of green projects.