Pinnacle West Capital Corporation is an energy holding company that conducts business through its subsidiaries, Arizona Public Service Company (APS), El Dorado Investment Company (El Dorado) and Pinnacle West Power, LLC. The Company's business segment is its regulated electricity segment, which consists of traditional regulated retail and wholesale electricity businesses (primarily electric service to Native Load customers) and related activities, and includes electricity generation, transmission, and distribution. APS provides electric service to approximately 1.4 million customers. APS is also the operator and co-owner of Palo Verde, a primary source of electricity for the southwest United States and the nuclear power plant in the United States. El Dorado owns debt investments and minority interests in several energy-related investments and Arizona community-based ventures. Palo Verde is a three-unit nuclear power plant located approximately 50 miles west of Phoenix, Arizona.