2008-08-14 23:59:03 -

www.aps.com - APS, Phoenix Media Contact: Steven Gotfried, 602-250-3040 RFP Contact: Gordon Samuel, 602-250-2298 Analyst Contacts: Rebecca Hickman, 602-250-5668 Lisa Malagon, 602-250-5671 Web site: www.aps.com/rfp APS is seeking business proposals for power aggregators who can deliver at least 1,500 megawatt hours from distributed energy systems (generators located at or near customers). Sources include roof-top solar electric systems, small windmills, biogas,

biomass, geothermal, hybrid wind, renewable natural gas and hydropower technologies.

The goal is to increase the quantity and lower the cost of distributed energy in APS' service territory. The power will help APS meet its growing demand for energy and assist in satisfying the distributed provision of the Arizona Corporation Commission's Renewable Energy Standard (RES).

The RES requires that by 2025, 15 percent of the energy APS provides to customers must come from renewable energy sources. The distributed provision states that 30 percent of the renewable energy must come from distributed sources.

Interested parties are encouraged to participate in a bidder's conference on September 5, 2008. Additional information about the conference and the RFP is available online at www.aps.com/rfp.

APS, Arizona's largest and longest-serving electricity utility, serves about 1.1 million customers in 11 of the state's 15 counties. In 2008, APS won its second Edison Award in recognition of innovative leadership and operational excellence in the electric industry. Given annually by the Edison Electric Institute, the Edison Award is considered the industry's most prestigious honor. With headquarters in Phoenix, APS is the principal subsidiary of Pinnacle West Capital Corp. (NYSE: PNW).

Company Issues Request for Proposal (RFP)