Palo Verde's Performance Perfect for Summer
All Three Units Operate at Full Power, Set Production Record

October 7, 2009

The Palo Verde Nuclear Generating Station^®, the nation’s largest power producer, simultaneously operated all three units at full power all summer, keeping homes and businesses cool amid record heat.

Since the completion of Unit 3’s planned maintenance and refueling outage in May, all three units at Palo Verde generated electricity at maximum capacity for 127 consecutive days. The simultaneous run of all three units continued until early Saturday when Unit 2 was powered down for a planned maintenance and refueling outage. Units 1 and 3 remain at 100 percent power.

This is the third consecutive time in the past 18 months that all three units ran together continuously for 100 days or more between planned outages.

During the past four months, the plant produced approximately 11.5 million megawatt-hours of electricity. This represents a new production record during the months of highest power demand by APS customers, according to Randy Edington, Executive Vice President and Chief Nuclear Officer for APS, Palo Verde’s operating utility.

“Palo Verde’s record performance is the result of strong performance by our employees and continual improvements to make plant equipment as good or better than new,” said Edington. “We are committed to safely and efficiently generating electricity for the long term, which means investing in the knowledge of our workforce and investing in the equipment.”

The power provided by the plant serves about four million people in the Southwest with about half serving Arizona customers. The remaining power is spread among California, New Mexico and Texas.

Palo Verde is jointly owned by APS, Salt River Project, Southern California Edison Co., El Paso Electric, Public Service Co. of New Mexico, Southern California Public Power Authority and the Los Angeles Department of Water & Power.

APS, Arizona’s largest and longest-serving electricity utility, serves about 1.1 million customers in 11 of the state’s 15 counties. With headquarters in Phoenix, APS is the principal subsidiary of Pinnacle West Capital Corp. (NYSE: PNW).

Betty Dayyo, APS Media Contact
(602) 250-2309

Jim McDonald, APS Media Contact
(602) 250-3738