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Nuclear Energy Institute
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Nuclear Energy Industry Sustains Near-Record Levels of Safety, Operating Performance

WASHINGTON—America’s nuclear power plants, providing electricity to one of every five U.S. homes and businesses, continued to operate at high levels of efficiency and safety in 2004, according to plant performance indicators compiled by the World Association of Nuclear Operators (WANO).

The U.S. nuclear energy industry set record-high levels of electricity production and efficiency, while also nearing record performance in areas including safety system performance, worker safety and programs to protect workers from radiation exposure.

These areas are among the performance indicators tracked by London-based WANO. The milestones were achieved even as many facilities conducted major equipment replacement projects that position the power plants to better serve customers and sustain excellence over the long term.

In 2004, 103 nuclear power plants located in 31 states generated 788.5 billion kilowatt-hours (kwh) of electricity, enough to supply electricity for 60 million people. Electricity production in 2004 was one percent higher than the record-high 780 billion kwh of electricity generated in 2002.

WANO reported the U.S. industry’s unit capability factor—a measure of efficiency—at 91.2 percent, equaling the record-high achieved in 2002 and exceeding the industry goal set for 2005. This is the fourth time in the past five years that the median capability factor has topped 90 percent. Unit capability factor is the percentage of maximum electricity a plant can supply to the electric grid, limited only by factors within the control of plant managers.

“The 2004 performance indicators are testament to the professionalism and dedication to safety and excellence that are exhibited on a daily basis by the men and women who work at nuclear power plants across the nation,” said NEI President and Chief Executive Officer Skip Bowman. “The operational and safety excellence that is being achieved is part and parcel of the reason that clean nuclear energy is positioned to enhance U.S. energy diversity and energy security in the decades to come.”

The performance data compiled by WANO is analyzed by the Atlanta-based Institute of Nuclear Power Operations (INPO), which promotes excellence in U.S. nuclear power plant safety and operations. INPO uses the data to help set challenging benchmarks of excellence against which safety and plant operation can be measured. Other highlights of the nuclear energy industry’s performance in 2004 include:

Unplanned Automatic Reactor Shutdowns: More than one-half (61 of 103) of reactors experienced zero unplanned automatic reactor shutdowns, with an overall median industry value of zero per plant. This is the seventh time in the past eight years that the median industry value has been zero. In 2003, the only year in that span when the median industry value was not zero (0.8 per plant), nine unplanned shutdowns occurred during the Aug. 14 blackout that affected much of the Midwest and East Coast.

In 2004, the total number of unplanned automatic shutdowns was 59.

Safety System Performance. For the 10th straight year, 94 percent or more of key safety systems met industry goals for availability. The three key safety systems are two main cooling systems and back-up power supplies used to respond to unusual situations.

Last year, 97 percent of the key safety systems met their availability goals. Nuclear power plants are built with redundant 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.

Forced Loss Rate. The 2004 median value of 1.2 equals the best ever level achieved, and represents a notable improvement from 2003. Forced loss rate measures unplanned plant shutdowns or power reductions. A low value reflects that plants have effective equipment reliability programs.

Worker Safety. Already one of the safest industrial work environments, U.S. nuclear plants continued to post a sterling industrial accident rate. In 2004, the rate equaled the 2003 rate of only 0.25 industrial accidents per 200,000 work-hours, a near-record low. This is better than the industry goal set for 2005. Statistics from other industries through 2003 as compiled by the Bureau of Labor Statistics show that it is safer to work at a nuclear power plant than in the manufacturing sector.

Collective Radiation Exposure. The WANO indicators showed that collective radiation measurements for plant workers remained well within federal safety standards. At pressurized water reactors (PWRs), the collective radiation measurement declined to a record low, besting both the prior low recorded in 2001 and the 2005 industry goal. The 2004 record was achieved even though several reactors undertook major equipment replacement projects—including new reactor vessel heads—that extended plant shutdowns beyond normal refueling periods. At boiling water reactors (BWRs), the collective radiation measurement was the third-lowest on record. All three of the lowest median measurements at BWRs have been achieved in the past three years.

To view charts of the WANO performance indicators for U.S. nuclear power plants, go to the Nuclear Data section of NEI’s web site at .


The Nuclear Energy Institute is the nuclear energy industry’s policy organization. This news release and additional information about nuclear energy are available on NEI’s Internet site at