PHOENIX - June 3, 2008

If it’s time to change out your air conditioning unit or heat pump, rebates from Arizona Public Service Company can help offset the cost of that investment, and installing high-efficiency AC units can also help customers begin saving money immediately.

Under the APS AC Rebate program, residential APS customers who replace their existing heat pump or air conditioning units with new high-efficiency systems may be eligible for a rebate of up to $400. And if customers have a Quality Installation done by an APS Qualified Contractor they could be eligible for an additional $100, for a total of $500 in rebates from APS.

“With thousands of APS customers changing out air conditioning units each year, this is a good opportunity to save money now and in the future,” said Jim Holbrook, APS program manager. “The program is easy for customers to use, and rebates arrive within weeks. The rebates help to offset the extra cost of upgrading to high-efficiency equipment. It’s a win for customers and the utility because these high-efficiency units will save energy during the summer for the lifetime of the equipment.”

Customers may qualify for rebates of $250 on units that are rated at 14 SEER (Seasonal Energy Efficiency Ratio) and 11.5 EER (Energy Efficiency Ratio) and $400 on units rated at 16 SEER and 12.25 EER. These ratios provide efficiency ratings for an air conditioning system or heat pump. While the SEER rating measures efficiency over a typical summer season, EER is another important efficiency rating that measures efficiency at peak summer temperature conditions. In Arizona’s hot climate, the ratings are important measures that can translate into significant future energy savings.

According to Holbrook, homes built between 1976 and 1980 typically had 7 SEER units. “Replacing those with a 16 SEER unit could reduce the heating and cooling portion of customers’ electricity bills up to 50 percent,” said Holbrook.

To qualify for the rebates, customers’ equipment must:

- Meet both the SEER and EER ratings; - Be a new installation that replaces an existing heat pump or air conditioner in an existing home served by APS. Units must apply to the entire house; window units do not qualify for a rebate; and - Be installed by a contractor who is a licensed heating, ventilation and air conditioning (HVAC) contractor in Arizona.

Rebate amounts are per unit for residential HVAC systems and are limited to five units per home. To apply for a rebate, customers simply need to complete a rebate application form, available at aps.com, attach a copy of their paid invoice and proof of purchases, and mail the complete package within six months of the installation date to:

APS AC Rebate Program 2001 N. 3rd Street, Suite 106 Phoenix, AZ 85004

APS encourages customers to verify that equipment they are interested in purchasing qualifies for an APS AC Rebate before they buy it by calling l-800-305-0182. The indoor and outdoor unit model numbers will be needed when customers call this number to check the SEER/EER ratings. Customers will receive their rebates between six to eight weeks after submittal of their completed package to APS.

For a referral to an APS Qualified Contractor that can offer the additional $100 Quality Installation rebate customers should call the APS Energy Answer Line at 602-371-3636 in Phoenix, or 1-888-890-9730 outside the Phoenix area.

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).