Sungevity designers use software and satellite imagery to design a solar array and generate a quote.

Residential solar installer Sungevity said today it raised $15 million which will allow it to offer its services across the country.

The Oakland, Calif.-based start-up specializes in offering a quote to homeowners for solar photovoltaic systems within 24 hours. Rather than send out a technician, Sungevity employees use satellite imagery to view rooftops, design a system, and generate a quote.

The company also offers a solar leasing program in which people pay a monthly fee, rather than pay the cost of solar panels up front. It's a model developed only a few years ago but which has led to the creation of few fast-growing companies, including Solar City and SunRun.

With the money, the company will be able to expand its quote and lease offerings in regions outside California, where it works now. "Broader resources will allow this company to serve an exploding market for solar leases, enabling more U.S. homeowners to get the benefits of solar without having to front the full cost of their systems," said board member A. George Battle, who also serves on the boards of Netflix, LinkedIn, and OpenTable.

The investment in a solar installer reflects the current direction of early-stage solar investing. With fierce price competition around solar panels, investors appear to be showing more interest in taking cost out of the installation and service side of the business.