The Electric Power Research Institute (EPRI), Palo Alto, Calif., has been awarded numerous SunShot projects, says Cara Libby, EPRI technical leader and project manager in solar energy. PV's low-level cost of electricity has reduced interest in CSP, but EPRI, with Italian utility Enel Spa, is participating in the Archimede CSP project for research into using molten salt for a parabolic-trough plant's working fluid. Results from the project could help to renew generation using CSP in the U.S.

Alternative Approach

SolarCity Corp., San Mateo, Calif., has a different business model from many solar players': The firm installs mostly only rooftop solar modules. Most are for residential use, but some commercial installations are as large as 45 MW. Self-performing the work, the firms offers customers free roof installation and guarantees production, insurance and monitoring. The customer pays for only the power produced at a rate discounted 10% to 15% from the utility's rate for residential customers, says Jonathan Bass, vice president of communications. In building generation and selling power to the customer, it operates similarly to a utility, but it is not regulated by the Public Utilities Commission, he adds.

Generation technology trends may shift and business models diversify, but the road has not ended for electricity generation from solar energy. Driven by a combination of market forces, technology development and good public policy, solar electric generation appears to be well on its way to making a solid contribution to the U.S. power picture.