BRIDGMAN, Mich., March 1, 2010 – American Electric Power’s (NYSE:AEP) Cook Nuclear Plant’s Unit 1 is scheduled to shut down early Wednesday to begin its 23rd refueling outage cycle. The 1,030-megawatt (MW) Unit 1 has been safely operating online since Dec. 20, 2009, following 15 months of extensive repair to its turbine.

Each of Cook’s two units requires refueling every 18 months. Aside from refueling the reactor and performing regular maintenance and testing work, the current outage will also include some key equipment modifications such as Reactor Protection System Process Transmitter upgrades, a Control Rod Indication System upgrade, an Emergency Diesel Generator Fuel Oil System upgrade, Reactor Vessel Alloy 600 weld mitigation activities and Reactor Vessel 10-year inspection activities.

“The improvements made to Unit 1 during this refueling outage demonstrate AEP’s ongoing commitment to the future of Cook for the benefit of our customers in Indiana and Michigan,” said Joe Jensen, AEP senior vice president and chief nuclear officer.

Over the course of the outage, more than 850 contracted workers will supplement the regular 1,300-person plant staff. Approximately 10,000 maintenance, inspection and equipment modification job activities and more than 205,000 work-hours are scheduled.

At full capacity, the 1,030-net MW Unit 1 and 1,077-net MW Unit 2 combined produce enough electricity for more than one and one half million average homes.

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 MW 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.