UPDATE 1-AEP shuts Mich. Cook 2 reactor for work

(Updates with company comment)

NEW YORK, Aug 18 (Reuters) - American Electric Power Co Inc (AEP.N) shut the 1,077-megawatt Unit 2 at the Cook nuclear power station in Michigan on Aug. 16 for maintenance, a spokesman for the plant said Monday.

He could not say when the unit would return to service due to competitive reasons.

Electricity traders guessed the unit would return within a week.

The spokesman said plant personnel were working on the turbine control system.

On Friday, the unit was operating at full power.

The 2,106 MW Cook station is located in Bridgman in Berrien County, about 80 miles east of Chicago. There are two units at the station, 1,029 MW Unit 1 and the 1,077 MW Unit 2, which entered service in 1975 and 1978.

Unit 1 continued to operate at full power.

One MW powers about 800 homes in Illinois.

In 2005, the NRC renewed the plant's original 40-year operating licenses for both units for another 20 years to 2034 and 2037.

AEP, of Columbus, Ohio, owns and operates more than 38,000 MW of generating capacity, markets energy commodities, and transmits and distributes electricity to more than 5 million customers in 11 states. (Reporting by Scott DiSavino; Editing by John Picinich)