DTE Energy Co. says it shut down its Fermi 2 nuclear power plant because of an excess of hydrogen gas in a cooling system for the main electrical generator.
DTE spokesman Guy Cerullo tells the Monroe Evening News that the plant shut down about 9:30 a.m. Wednesday.
Cerullo says operators saw that water in part of the cooling system for the generator contained higher than normal amounts of hydrogen.
The generator is on the non-nuclear side of the plant and has two separate cooling systems for its different sections. One uses water and the other hydrogen.
An increase in hydrogen gas in the water-cooled system decreases its efficiency.
The 1,100 megawatt reactor is next to Lake Erie in Monroe County's Frenchtown Township, near Monroe.