FRENCHTOWN TWP. (WWJ/AP) – DTE Energy has shut down its Fermi 2 nuclear power plant near Monroe because of an excess of hydrogen gas in a cooling system for the main electrical generator.

Fermi 2 spokesman Guy Cerullo told WWJ Newsradio 950 the shut down happened around 9:30 a.m. Wednesday when operators saw water in part of the cooling system contained higher than normal amounts of hydrogen.

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“Operators shut down the plant as a precautionary measure to protect the generator from heat damage. It’s important to remember that the generator is on the non-nuclear side of the plant, where the electricity is generated. It’s the same type of equipment that’s in any power plant, whether it’s powered by coal, natural gas or nuclear,” said Cerullo.

Cerullo said the generator has two separate cooling systems for its different sections: one uses water and the other hydrogen. He said an increase in hydrogen gas in the water-cooled system decreases its efficiency.

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No timetable is set for restart. An investigation into the elevated hydrogen gas levels is being conducted.

The 1,100 megawatt reactor is located next to Lake Erie in Monroe County’s Frenchtown Township.

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