Edison International, is a holding company of Southern California Edison Company (SCE). SCE is a public utility primarily engaged in the business of supplying electricity to an approximately 50,000 square-mile area of southern California. The SCE service territory contains a population of nearly 14 million people and SCE serves the population through approximately 5 million customer accounts.SCE's retail operations are subject to regulation by the California Public Utilities Commission (CPUC). SCE has a five tier residential rate structure. SCE supplies electricity to its customers through transmission and distribution networks. Its transmission facilities, which are located primarily in California but also in Nevada and Arizona, deliver power from generating sources to the distribution network and consist of lines ranging from 33 kilovolts to 500 kilovolts and substations.