A SREC is a tradable certificate that represents the clean energy benefits of the electricity generated by a solar electric system. A SREC is issued for every 1,000 kWh generated by the system and can be sold to generate additional income. California law (Public Utilities Code §399.12[f]) defines a REC as: "a certificate of proof, issued through the accounting system established by the Energy Commission… that one unit of electricity was generated and delivered by an eligible renewable energy resource.