First, all solar installers need to keep a legitimate and active license from the Contractors State License Board (CSLB). They are able to hold any of the following being certified for solar installations in California: a solar contractor license, an electrical contractor license or maybe a common making contractor license. https://www.americanarraysolar.com/how-do-the-solar-installers-fresno-decide-which-solar-panels-to-install/