Nuclear Facilities Weather Second Frigid Blast
Jan. 22, 2014—A second blast of polar air this month in the form of Winter Storm Janus—along with more subfreezing temperatures throughout the eastern United States—didn’t ice out nuclear energy plants, which maintained close to 100 percent output during the first days of the chill.
With a few plants reporting less than 100 percent capacity and a few others off line for refueling or for other reasons, the average operating capacity for all facilities was 97.4 percent on Tuesday and 93.5 percent on Wednesday.
During the storm Tuesday night, Constellation Energy Nuclear Group’s Calvert Cliffs nuclear energy facility in Maryland experienced an electrical malfunction on the non-nuclear side of the plant. CENG spokesman Kory Raftery said in a phone interview that the plant’s safety systems responded as designed and put both reactors into a safe shutdown condition. Raftery said plant operators are investigating the cause of the incident, after which they will take actions to return the reactors to service.*
While the blast of frigid air from the first arctic storm receded quickly, this time around temperatures in a large part of the country are expected to remain below freezing for the rest of the week.
The value of the nuclear facilities during both recent bouts of freezing weather has proven to be their ability to operate without competition from home heating needs, which stressed natural gas prices and supply. The supply volatility drove natural gas prices to a record high earlier in January but even that has now been surpassed. Dow Jones Business News reported natural gas prices of $135 per million Btus for New York on Jan. 21, a record high. On the Friday before the storm hit, according to the report, prices ranged between $10 and $25 per million Btus. By contrast, nuclear energy fuel costs remained untouched at about $0.50 per million Btus.
In the first storm, according to the U.S. Energy Information Administration, utilities pulled a record 287 billion cubic feet of gas supplies from storage tanks in the week ending Jan. 10. Still, northeast grid operator ISO-NE reported that nuclear energy provided more electricity in New England than natural gas, 29 percent to 27 percent. Additionally, shuttered coal and oil facilities reopened to relieve the brief natural gas shortage.
NEI President and CEO Marvin Fertel made the point in a recent speech that the performance of nuclear energy facilities during the first spate of cold weather demonstrated the value of energy diversity, noting that the electricity grid’s ability to maintain performance despite record-high winter demand “has been founded on a system that relies on an ‘all of the above’ strategy.”
“The polar vortex is just the most recent reminder that the reliability of our electricity infrastructure is critical and at times at risk,” Fertel told the United States Energy Association last week (see accompanying story in this week’s Nuclear Energy Overview). “Diversity in technology and fuel supply and continued investment in the grid and environmental control technologies are prerequisites for the successful transition of our electric sector over the next two decades,” he said.
Still, nuclear energy facilities are not completely invulnerable to cold-weather issues, though plant operators and the Nuclear Regulatory Commission mitigate these at several points before and during anticipated extreme weather events. NRC resident inspectors use an “Adverse Weather Protection” inspection procedure to check that plants are ready for extreme weather, including cold. The reviews usually occur near the beginning of each season.
All the nuclear facilities weathered the earlier vortex-driven deep freeze, with one plant going off line during that period. Beaver Valley 1 in Pennsylvania shut down safely due to a transformer issue, but operator FirstEnergy has not determined whether the cold weather contributed. Beaver Valley 2 continued to produce electricity.
The Dresden nuclear energy facility in Illinois is helping its neighbors cope with the cold by providing more than electricity. Warm water from the plant’s cooling pond is being siphoned into the freezing Kankakee River to raise the river’s temperature and prevent an ice jam. The water is heated to about 70 degrees as it passes through the reactor’s condenser. The condenser, not part of the nuclear side of the plant, turns the steam that powers the generator back into water, which is then recycled into the plant.
*Article revised Jan. 23.