By Katie Fehrenbacher of GigaOM | June 3rd, 2011

Solar rooftops only work in specific environments: an area with enough sun, a roof with the right tilt, a state or city with strong subsidies. But a company called Geostellar is using big data tools to help its solar installer customers deliver more solar panels to more rooftops in places where it actually makes economic sense. Later this year, the company plans to release an open API — so developers can build applications on top of it — and eventually, the company plans to launch a consumer-facing site

Year-old Geostellar pulls together at least 25 different types of data into its platform, including information about weather, shadows, roof slope, closest transmission lines, property values, land use, electricity rates, solar subsidies, and solar hazards. In addition, the company is constantly adding in more data sets like information about brownfields — a sudden hot area for solar installers — and data from pertinent recent legislation explained Geostellar CEO David Levine in an interview with me this week.

Read more: New York Times: Using Big Data to Make Solar Smarter

How Much Energy Can Your Roof Generate?

By Christopher Steiner | April 4th, 2011

David Levine thinks there's gold in mapping the solar potential of every home--one rooftop at a time. 

It was a throwaway comment, but it changed David Levine's life. Levine worked for Lanworth, which predicts crop yields with satellite imagery. During a meeting in 2009 a Dean Foods (DF) executive who used Lanworth's software to hedge large grain purchases wondered aloud how he might better control his company's energy consumption. Levine's eyes carefully combed the room; the remark had gone unnoticed. "But for me," he says, "the light went off immediately."

Soon afterward Levine left Lanworth, waited out a six-month noncompete period, then launched Geostellar, which seeks to catalog the solar power potential of every roof in the world. As solar equipment becomes more affordable, a land grab for rooftop real estate is heating up. Prospectors, such as SolarCity and Sungevity, guarantee building owners low electrical costs for the right to install panels and sell excess power back to the grid. Big utilities like AES, Next Era, Constellation Energy (CEG) and Duke Energy (DUK) can use the data, too, for prospecting commercial-scale solar sites. Further stoking development, Wall Street has interest in securitizing solar panels' income streams.

Read more: Forbes: Sun King