Total U.S. nuclear plant availability rebounded early Dec. 13 to 94.29%, rising from 93.69% on Dec. 12 and still much higher than the 90.68% reported on the same day last year.

Helping to boost total U.S. production was the return of two reactors. Exelon Corp.'s Nine Mile Point 1 in New York was operating at 25% early Dec. 13. The reactor was manually scrammed Dec. 10 due to high vibrations on the main turbine. In addition, unit 1 of Entergy Corp.'s Arkansas Nuclear One in Arkansas was warming up at 1% early Dec. 13. The plant was taken offline on Sept. 24 for planned seasonal work.

Exelon's Three Mile Island 1 plant in Pennsylvania saw output rise from 7% on Dec. 12 to 97% early Dec. 13. The unit was idled Dec. 1 to perform planned maintenance on one of several pumps that provide water to the reactor.

Conversely, Exelon's Oyster Creek plant in New Jersey saw output curtailed to 45% early Dec. 13, down from 85% on Dec. 12.

For details of U.S. nuclear power plant operations, visit our Nuclear Availability and Status and Outage Pages.