WASHINGTON, D.C.—U.S. nuclear energy facilities in 2011 recorded the lowest number of unplanned shutdowns in more than a decade and achieved near-record levels of reliability and safety performance, according to safety and operations data compiled by the World Association of Nuclear Operators (WANO) and the Institute of Nuclear Power Operations (INPO). U.S. companies achieved these milestones despite a year marked by severe weather events that caused extensive damage to communities in numerous states.
Also, the industry reached record levels for industrial safety, placing it among the best industries in U.S. Bureau of Labor Statistics rankings.
The nuclear energy facilities that supply electricity to one of every five U.S. homes and businesses recorded 62 unplanned shutdowns last year, three fewer than the decade-low 65 that occurred in 2005. The record-low number of unplanned shutdowns helped America’s nuclear power plants achieve reliability levels on par with the high operational efficiency sustained throughout the past decade.
Unplanned shutdowns can result from severe weather or grid disturbances that trigger safety responses. In 2011—despite tornadoes in the Southeast, the Virginia-centered East Coast earthquake, Hurricane Irene and flooding in the Midwest—U.S. nuclear energy facilities posted a capability factor of 91.4 percent. Last year marked the 10th straight year that a median capability factor of at least 91 percent has been achieved. Capability factor measures the amount of time a facility is online and producing electricity. The industry’s record-high capability factor, 92 percent, was set in 2005.
“Plants with a high unit capability are successful in reducing unplanned outages and completing scheduled work effectively during planning outages,” states INPO’s report on the industry performance indicators.
“America’s nuclear energy facilities performed extremely well in the face of a host of natural challenges,” said Tony Pietrangelo, the Nuclear Energy Institute’s senior vice president and chief nuclear officer. “The industry’s employees can take pride in this achievement while recognizing that their commitment to safety and excellence must never waver. Plant safety is the foundation of our industry’s ability to help make the United States a better, more secure place to live, work and raise our families.”
U.S. nuclear energy facilities last year sustained the high safety performance that has been the underpinning of the industry’s ability to improve reliability and increase electricity production, Pietrangelo said. Since 1990, the U.S. nuclear energy industry has increased its electricity production nearly 40 percent—last year generating 790 billion kilowatt-hours of electricity—from approximately the same number of reactors.
Other performance indicator data on U.S. facilities follows:
Safety System Performance. For the 10th straight year, key backup safety systems concurrently met availability goals more than 93 percent of the time. Nuclear power plants are built with multiple safety systems and backup power supplies so these systems are available, if needed, even when maintenance is being performed on a similar system or component. The three principal backup safety systems are two main cooling systems and backup power supplies used to respond in the event of unusual situations. Each system at every plant has an availability goal just shy of 100 percent due to maintenance and testing, and 95 percent of these backup safety systems met their goal in 2011, assuring that multiple layers of safety were in place as designed.
Industrial Safety. The nuclear industry is one of the nation’s safest working environments. U.S. facilities continued to post a low industrial accident rate in 2011 achieving a record 0.06 industrial accidents per 200,000 worker-hours, well below the 2015 goal of 0.1. Statistics from other industries through 2010, compiled by the U.S. Bureau of Labor Statistics, show that it is safer to work at a nuclear power plant than in the manufacturing sector and even pharmacies and personal care stores, real estate, and financial sectors.
Reactor Capability. America’s 104 reactors continued to operate at high levels of efficiency—far above other electricity sources. Last year marked the eighth time in the past 10 years that the median capability factor has been at least 91.4 percent. Capacity factor, a related metric that measures total electricity generated as a percentage of year-round potential generation, was 89 percent in 2011, according to data compiled by the U.S. Energy Information Administration.
Unplanned Reactor Shutdowns. The 2011 total of 62 unplanned automatic or manual shutdowns was the lowest level achieved in the past 12 years.
Forced Capability Loss Rate. The 2011 median value of 1.4 percent capability loss remained near historically best levels. Forced capability loss rate measures a plant’s outage time and power reductions that result from unplanned equipment failures, human error or other limiting conditions when the plant is expected to be generating electricity. The 2015 goal for this indicator is a median value of one percent. In the mid-1990s, the median value exceeded five percent, but it has been under two percent each year since 2001 and 1.5 percent or lower for seven consecutive years.
“These 2011 safety and performance indicators provide overwhelming evidence of the resiliency of our plants in confronting weather challenges and confirm the unwavering commitment of the industry’s dedicated men and women to safe and efficient operations,” Pietrangelo said.
WANO, headquartered in the United Kingdom, compiles nuclear energy industry performance data annually. Data for the U.S. industry is analyzed by the Atlanta-based Institute of Nuclear Power Operations to help set challenging benchmarks of excellence against which safety and plant operation can be measured. INPO was established by the U.S. nuclear energy industry in 1979 to promote excellence in safety and operating performance above and beyond federal regulatory requirements.
“The Nuclear Regulatory Commission’s recent approval of licenses to build new reactors in Georgia and South Carolina, coupled with recent polling by Gallup and others showing public confidence in the safe operations of our plants, demonstrates that nuclear energy has an important role to play as a dependable low-carbon source of electricity,” NEI’s Pietrangelo said.