Against the backdrop of bitter cold temperatures across much of the United States, one Midwest nuclear unit is returning to service while two in the East have unexpectedly gone offline.
An Xcel Energy (NYSE:XEL) spokesperson confirmed Jan. 7 that that Prairie Island 2 is returning to service and should be back to full power within days. The Nuclear Regulatory Commission (NRC) listed the unit at 29% power in its Jan. 7 reactor status report.
The roughly 550-MW pressurized water reactor (PWR) in Minnesota began a regularly-scheduled outage in late September 2013. In addition to refueling, the company was also scheduled to replace two steam generators at the facility.
Meanwhile, the NRC reported Jan. 7 that the FirstEnergy (NYSE:FE) Beaver Valley 1 unit in Pennsylvania and the Entergy (NYSE:ETR) Indian Point 3 facility in New York State had both gone offline due to unplanned outages.
Entergy reported that Indian Point 3 automatically shut down at about 9:15 p.m. ET on Jan. 6 as a result of lowering water level inside one of the plant’s four steam generators. Water levels lowered inside the steam generator following a failure of a controller device that regulates the flow of water into the steam generator.
The shutdown was not connected to the cold weather, an Entergy spokesperson said. Indian Point 3 is a 1,000 MW PWR.
FirstEnergy’s Beaver Valley 1 automatically shut down at 4:59 p.m. Jan. 6 after experiencing an unexpected problem with the main unit transformer.
The main unit transformer converts power generated from the plant to the appropriate voltage for distribution through the transmission system, a FirstEnergy spokesperson said. The transformer is part of the “generation” portion of the plant rather than a “nuclear” component. This type of transformer is also found at fossil plants.
“A team has been formed to investigate the cause of the transformer issue and determine the repair plan,” the FirstEnergy spokesperson said. The plant will remain off line until the investigation and repair is completed.
“The team will consider a variety of factors during its intrusive diagnosis, including any potential impact of cold weather on the equipment,” the FirstEnergy representative said. A spare transformer is on site at Beaver Valley in the event a replacement is required. Replacement of the transformer would require a relatively short outage.
Beaver Valley 1 is a roughly 900-MW PWR.
Nuclear plant availability is of increased importance at a time when subzero or near-zero temperatures have driven up power demand across much of the nation. Power systems in multiple regions have issued alerts urging conservation.
The Tennessee Valley Authority (TVA) said Jan. 7 that it had narrowly missed matching its peak winter demand of 32,572 MW that was set on Jan. 16, 2009.