The Energy Northwest Columbia nuclear power plant near Richland, Washington returned to full power on Dec. 28 after going offline due to an unplanned outage on Dec. 18, according to data from the Nuclear Regulatory Commission (NRC).
The nuclear plant had experienced a full reactor scram before noon on Dec. 18 due to a load reject from the Bonneville Power Administration (BPA) Ashe substation, according to a preliminary event report filed with the NRC.
“Columbia safely shut down at 11:24 a.m. Dec. 18 following an equipment malfunction at the Bonneville Power Administration’s Ashe Substation located near Columbia, resulting in a rejected load on the 500 kilovolt line connecting the plant’s main output transformers to the substation,” Energy Northwest said in a statement. “In response, Columbia’s output breakers properly opened to separate the plant from any potential grid transients.”
The plant was listed at zero power as recently as Dec. 24. The unit resumed power generation on Christmas Day, Dec. 25.
It reached full power again on Dec. 28, according to NRC data. It had been at 99% power on Dec. 18 prior to going offline.
Columbia Generating Station, a 1,190-MW boiling water reactor (BWR) that produces enough electricity to power a city the size of Seattle and is the third largest generator of electricity in Washington state. All of Columbia’s electricity is sold at-cost to BPA. Ninety-two Northwest utilities receive a percentage of its output.