Ernie Garcia, firstname.lastname@example.org
A review of unplanned shutdowns from January 2012 to the present showed this year’s events happened within a short time frame, between May 7 and July 8, in contrast with events from other years that were more spread out, according to data released by Indian Point.
If a nuclear plant has more than three unplanned shutdowns in a nine-month period, its performance indicator could be changed by the federal Nuclear Regulatory Commission, which results in additional oversight. That’s what happened with Entergy’s Pilgrim Nuclear Power Station in Plymouth, Mass., after four unplanned shutdowns in 2013.
So far, Entergy said there doesn’t appear to be a pattern to the Indian Point shutdowns.
“You do want to look at these events holistically to see if there is something in common, but you also look individually to see what the causes were,” Nappi said. “A plant shutdown in and of itself is not a safety issue.”
The NRC is expected to release a quarterly report on Indian Point this month that will address the transformer failure and, by year’s end, is planning an inspection of the transformer and an analysis of transformer issues since 2007.
Besides its transformer-related inquiries, the other three shutdowns have not raised “any immediate safety concerns or crossed any thresholds that would result in additional NRC oversight,” agency spokesman Neil Sheehan wrote in an email.
The unplanned shutdowns at Indian Point and Pilgrim in Massachusetts were mostly preventable, said Paul Blanch, a former Indian Point employee with 45 years of nuclear power experience.
“For this to happen this frequently indicates a deeper problem,” he said. “I believe it’s management oversight in the maintenance of these plants.”
Nappi said the transformer that failed May 9 and caused a fire and oil spill into the Hudson was regularly monitored. Investigators determined the failure was due to faulty insulation.
“The transformer inspection and reviews were in accordance with our standards and industry expectations, yet there was no indication the transformer was going to fail,” Nappi said.
The NRC conducted a separate, but related special inspection into the May 9 incident that focused on a half-inch of water that collected in an electrical switchgear room floor. Inspectors determined a fire suppression system’s valve failed to close properly.
Inspectors noted in their report that Entergy knew about that problem since April 2011 and replaced the valve but didn’t discover the actual cause — a dysfunctional switch — until after the fire.
The nuclear energy industry judges a power plant on how continuously it produces energy, which is called a capacity factor.
There were 100 nuclear plants in the United States in 2014, a record year in terms of efficiency. In January, the Nuclear Energy Institute announced the U.S. average capacity factor was 91.9 percent.
Indian Point has an above-average efficiency rate. The plant’s Unit 2 and 3 reactors were each online more than 99 percent of the time during their most recent two-year operating cycles. They are currently in the middle of other cycles.