BRIDGMAN, Mich. - One of the two units at Cook Nuclear Power Plant will remain out of service until September 2009 at the earliest, American Electric Power has announced.
Repairing and replacing the unit's damaged turbine rotors is estimated to cost up to $332 million, the company said.
Cook's Unit 1 has been out of service since Sept. 20 after severe vibrations, caused when broken low-pressure turbine blades damaged the main turbine and generator.
The Cook Nuclear Plant on U.S. 12 is about 25 miles north of Michigan City.
A successful repair could allow the unit to operate at reduced power by next September, according to a company statement, but the rotors will ultimately be replaced to ensure the long-term viability of the unit.
If the repair is not successful, Unit 1 will not restart until new rotors are available. In that case, it would not be up and running until 2010.
Three new low-pressure turbines made by Siemens were installed in Unit 1 in 2006. Blades broke on two of the three turbines. The high-pressure turbine and main generator are original plant equipment made by General Electric.
AEP said it expects that all costs incurred to return Unit 1 to service will be recovered through insurance, vendor warranty or the regulatory process.
This repair option includes straightening the rotor shafts and modifying each rotor by removing one or two of the largest rows of blades until new rotors can be made.
Returning to service without one or two rows of blades would result in a power reduction of 100 to 250 megawatts from Unit 1's rated net capacity of 1,030 megawatts. A megawatt is roughly equal to the energy needed to power 1,000 homes.
Work to straighten the first rotor shaft has started. Work on the third rotor will finish in mid-January.
Cook Communications Manager Bill Schalk said the issues with Unit 1 will not affect AEP employment at the plant. More than 400 contractors are working on additional inspections and repairs at the plant, he said. AEP expects sufficient reserve generating capacity to make up for the loss of capacity at Unit 1.
Schalk said the Cook plant produces roughly 6 percent of AEP's total power generation.
The refueling outage for Unit 2, which continues to operate at full power with a rated net capacity of 1,070 megawatts, will take place as scheduled in the spring of 2009.
The refueling outage scheduled in the fall of 2009 for Unit 1 will be moved to 2010, with the date dependent on when it returns to service.
