TULSA, Okla., March 4, 2008 – Public Service Company of Oklahoma (PSO), a unit of American Electric Power (NYSE: AEP), has begun commercial operation of new peaking generation units at Southwestern Station (SWS), located near Anadarko, Okla.
 
Two 85-megawatt (MW) gas-fueled combustion turbines (CT) at SWS were declared commercially available Feb. 29, 2008.  Plans for the new units were announced in March 2006.  Construction began in July 2007.
 
The addition of 170 MW of peaking capacity at Southwestern increases the plant’s total generating capacity to 608 MW.
 
“Completion of the peaking units at Southwestern Station is good news for PSO and our customers,” said Stuart Solomon, PSO president and chief operating officer.  “The addition of these two new units helps PSO meet our customers’ growing demand for electricity.”

Along with the addition of the new units at SWS, two more 85 MW peaking units are in the final stages of testing at PSO’s Riverside Station in Jenks, Okla., and are expected to be commercially available in the next few weeks.
 
The addition of all four new units will help PSO reliably meet the ever-increasing need for power during periods of peak demand.
 
PSO, a unit of AEP with headquarters in Tulsa, Okla., serves approximately 520,000 customers in eastern and southwestern Oklahoma.

News releases and other information about PSO can be found on the World Wide Web at PSOklahoma.com.
 
American Electric Power is one of the largest electric utilities in the United States, delivering electricity to more than 5 million customers in 11 states. AEP ranks among the nation’s largest generators of electricity, owning nearly 38,000 megawatts of generating capacity in the U.S. AEP also owns the nation’s largest electricity transmission system, a nearly 39,000-mile network that includes more 765 kilovolt extra-high voltage transmission lines than all other U.S. transmission systems combined. AEP’s transmission system directly or indirectly serves about 10 percent of the electricity demand in the Eastern Interconnection, the interconnected transmission system that covers 38 eastern and central U.S. states and eastern Canada, and approximately 11 percent of the electricity demand in ERCOT, the transmission system that covers much of Texas. AEP’s utility units operate as AEP Ohio, AEP Texas, Appalachian Power (in Virginia and West Virginia), AEP Appalachian Power (in Tennessee), Indiana Michigan Power, Kentucky Power, Public Service Company of Oklahoma, and Southwestern Electric Power Company (in Arkansas, Louisiana and east Texas). AEP’s headquarters are in Columbus, Ohio.