U.S. nuclear energy facilities operated at high levels of safety and efficiency in 2012, according to newly released performance metrics compiled by the World Association of Nuclear Operators and the Institute of Nuclear Power Operations. In several key areas, commercial U.S. facilities either matched or improved upon outstanding levels of performance that helps make nuclear energy a vital component of the nation's diverse portfolio of electricity sources.
The nation's 100-plus nuclear power plants matched their record-low number of unplanned shutdowns—62—set just a year earlier. This is the fourth time in the past eight years that fewer than 70 unplanned shutdowns have occurred, with the result that facilities continue to reliably generate large amounts of electricity around-the-clock to help stabilize the electric grid and sustain economic growth.
As has been the case every year for the past decade at least, key backup safety systems concurrently met availability goals more than 93 percent of the time, assuring that multiple layers of safety were in place as designed.
"The 2012 performance indicators verify that the nuclear energy industry has in place a strong safety culture that is rooted in continuous learning, benchmarking, information sharing on operational issues, and constant training," said Anthony Pietrangelo, the Nuclear Energy Institute's senior vice president and chief nuclear officer. "The dedicated professionals who operate and maintain our plants understand that it is imperative that we operate at exemplary levels of safety to maintain the far-reaching benefits of nuclear energy."
The 100-plus nuclear power plants operating in 31 states neared record levels of efficiency even though four were out of service for most or all of last year. In 2012, U.S. facilities operated at a median capability factor of 91.2 percent, according to the WANO data. This marked the 13th straight year that a median capability factor of 91 percent or higher 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.
Last year U.S. nuclear plant generation was more than 769 billion kilowatt-hours of electricity—19 percent of the nation's total electricity supply and nearly two-thirds of the supply from low-carbon electricity sources including hydroelectric power plants and renewable technologies. The increase in the industry's electricity production from 1990 is equal to adding 24 new 1,000-megawatt power plants to the grid.
Additional evidence of nuclear plants' reliability came during Hurricane Sandy. Of the 34 reactors from South Carolina to Vermont in Hurricane Sandy's path, 24 continued to operate safely and generate electricity throughout the event. Seven reactors already were shut down for refueling or inspection, and three in New Jersey and New York safely shut down, as designed, because of storm conditions or grid disturbances.
An industrial accident involving a 500-ton component earlier this month at an Arkansas power station tragically resulted in the death of a contract employee and injuries to several other workers. The WANO data shows that such incidents are very rare. In 2012, the industry actually posted its best industrial safety record ever, with only 0.05 industrial safety accidents per 200,000 worker-hours.
Other performance indicator data on U.S. facilities follows:
Safety System Performance. Key backup safety systems concurrently met availability goals 95 percent of the time in 2012. Nuclear power plants are constructed 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 encompass 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.
Industrial Safety. The 2012 industrial accident rate of 0.05 accidents per 200,000 worker-hours is well below the 2015 goal of 0.1. As proof of the industry's exacting standards, statistics from other industries through 2011, compiled by the U.S. Bureau of Labor Statistics, demonstrate that it is safer to work at a nuclear power plant than in the manufacturing sector, leisure and hospitality industries, and financial sectors.
Reactor Capability. America's 103 reactors continued to maximize their operating efficiency at a rate far above other electricity sources. For the ninth time in the past 10 years the median capability factor has been at least 91.2 percent, even with a number of reactors in extended shutdowns and more reactors in refueling outages. Capacity factor, a related metric that measures total electricity generated as a percentage of year-round potential generation, was 86.4 percent in 2012, according to data compiled by the U.S. Energy Information Administration.
Unplanned Reactor Shutdowns. The 2012 total of 62 unplanned automatic or manual shutdowns matched the record low set in 2011, which was the lowest level achieved in the past 12 years.
Forced Loss Rate. The 2012 median value of 1.2 percent forced loss matched an historic best set in 2006. Forced loss rate measures a plant's outage time and power reductions that result from unplanned equipment failures, human error and 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 eight consecutive years.
"Last year was one of the nuclear industry's most demanding, as it began implementing its FLEX response strategy encompassing additional layers of safety from lessons learned from the Fukushima Daiichi accident, and weathering the strongest Atlantic tropical storm on record," Pietrangelo said. "The 2012 safety and performance indicators are a testimony to the resiliency of our plants and the dedication of the industry's men and women to safe and efficient operations no matter the challenges."
WANO, headquartered in the United Kingdom, compiles nuclear energy industry performance data annually (see 2012 charts). 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.
U.S. nuclear power plants generated 769 billion kilowatt-hours of electricity in 2012 at a cost below that of other sources of generation. In 2011 (final figures for 2012 are not available yet) the industry average electricity production cost (encompassing fuel and operations and maintenance expenses) was 2.19 cents per kilowatt-hour, lower than production costs at coal-fired power plants (3.23 cents/kwh) and lower than production costs at natural gas-fired power plants (4.51 cents/kwh).