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

WASHINGTON—The nuclear power plants that provide electricity to one of every five U.S. homes and businesses continued to operate at high levels of efficiency and safety in 2003, according to annual performance indicators compiled by the World Association of Nuclear Operators (WANO).

The U.S. nuclear energy industry approached near-record high levels in electricity production and efficiency, even though many power plants undertook major equipment replacement projects that extended plant shutdowns beyond normal refueling periods. These projects contributed to slight dips in some of the performance indicators tracked by London-based WANO, even though the investments in the facilities position the industry to better serve customers and sustain excellence over the long term.

In 2003, 103 nuclear power plants located in 31 states generated 764 billion kilowatt-hours (kwh) of electricity, enough to power nearly 70 million homes and businesses. This figure, announced by the Nuclear Energy Institute (NEI), represents a two percent drop from 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 89.8 percent, the fourth highest on record.

The dip in electricity production and capability factor reflect the planned extended shutdowns that occurred at many plants as they conducted, for example, more rigorous inspections of, and in some cases replaced, reactor vessel heads at pressurized water reactors. Vessel head replacement typically requires a minimum of 50 days.

“When put into perspective, the nuclear plant performance results for 2003 are every bit as impressive as the performance records being set in the years that preceded it,” said Joe F. Colvin, NEI’s president and chief executive officer. “The 2003 performance indicators show that the industry can continue to operate at top levels of excellence while making major commitments to ensure that safety and efficiency will be sustained at the highest levels years down the road.”

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 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 2003 include:

Unplanned Automatic Plant Shutdowns: Nearly half of the plants experienced no unplanned automatic reactor shutdowns, with an overall median industry value of 0.8 per plant. This is the first time since 1997 that the median industry value exceeded zero. The change can be attributed in part to the blackout that affected much of the Midwest and East Coast last August. Nine unplanned shutdowns were directly attributable to the Aug. 14 blackout. The U.S.-Canada Power System Outage Task Force, in its final report on the blackout released in early April, concluded, “The nine plants automatically shut down in a safe fashion to protect the plants from the grid transient. Safety functions were effectively accomplished with few problems, and the plants were maintained in a safe shutdown condition until their restart.”

For the year, the total number of unplanned shutdowns was 69. The average number of plant shutdowns from 1999-2003 was 59 per year.

Safety system performance. For the 11th straight year, more than 90 percent 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, 94.8 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.

Worker safety. Already one of the safest industrial work environments, U.S. nuclear plants improved their industrial accident rate for the fourth straight year, with the rate reaching a near record low of only 0.25 industrial accidents per 200,000 work-hours. This is lower 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 and even the real estate and finance industries.

Unit capability factor. The 2003 median capability factor of 89.8 percent is the fourth highest since WANO began collecting data and is only marginally lower than the 2005 goal of 91 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.

Collective radiation exposure. The WANO indicators showed that collective radiation measurements for plant employees remained well within federal safety standards, even though the industry’s performance at pressurized water reactors (PWRs) was slightly higher than 2002. This is due in large part to equipment upgrades that position these plants to have their licenses to operate extended for an additional 20 years. Boiling water reactors underwent equipment upgrades as well and saw a marginal, but inconsequential, increase in collective exposure to workers in 2003 over the previous year.

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