Drought could cut power from nuclear plants

LAKE NORMAN -- Nuclear reactors across the Southeast could be forced to throttle back or temporarily shut down later this year because drought is drying up the rivers and lakes that supply power plants with the massive amounts of cooling water they need to operate.

Utility officials say such shutdowns probably wouldn't result in blackouts. But they could lead to shockingly higher electric bills for millions of Southerners, because the region's utilities may be forced to buy expensive replacement power from other energy companies.

Already, there has been one brief, drought-related shutdown, at a reactor in Alabama over the summer.

"Water is the nuclear industry's Achilles' heel," said Jim Warren, executive director of N.C. Waste Awareness and Reduction Network, an environmental group critical of nuclear power. "You need a lot of water to operate nuclear plants." He added: "This is becoming a crisis."

An Associated Press analysis of the nation's 104 nuclear reactors found that 24 are in areas experiencing the most severe levels of drought. All but two are built on the shores of lakes and rivers and rely on submerged intake pipes to draw billions of gallons of water for use in cooling and condensing steam after it has turned the plants' turbines.

Because of the yearlong dry spell gripping the region, the water levels on those lakes and rivers are getting close to the minimums set by the Nuclear Regulatory Commission. Over the next several months, the water could drop below the intake pipes altogether. Or the shallow water could become too hot under the sun to use as coolant.

"If water levels get to a certain point, we'll have to power it down or go off line," said Robert Yanity, a spokesman for South Carolina Electric & Gas Co., which operates the Summer nuclear plant outside Columbia, S.C.

Extending or lowering the intake pipes is not as simple at it sounds and wouldn't necessarily solve the problem. The pipes are usually made of concrete, can be up to 18 feet in diameter and can extend up to a mile. Modifications to the pipes and pump systems, and their required backups, can cost millions and take several months. If the changes are extensive, they require an NRC review that itself can take months or longer.

Limited options

Even if a quick extension were possible, the pipes can only go so low. If they are put too close to the bottom of a drought-shrunken lake or river, they can suck up sediment, fish and other debris that could clog the system.

An estimated 3 million customers of the four commercial utilities with reactors in the drought zone get their power from nuclear energy. Also, the quasi-governmental Tennessee Valley Authority, which sells electricity to 8.7 million people in seven states through a network of distributors, generates 30 percent of its power at nuclear plants.

At Progress Energy, which operates four reactors in the drought zone, officials warned in November that the drought could force it to shut down its Harris reactor near Raleigh, according to documents obtained by AP. The water in Harris Lake stands at 218.5 feet -- just 3 1/2 feet above the limit set in the plant's license.

Lake Norman near Charlotte is down to 93.7 feet -- less than a foot above the minimum set in the license for Duke Energy's McGuire nuclear plant. The lake was at 98.2 feet just a year ago.

Duke is optimistic

"We don't know what's going to happen in the future. We know we haven't gotten enough rain, so we can't rule anything out," Duke spokeswoman Rita Sipe said. "But based on what we know now, we don't believe we'll have to shut down the plants."

If a prolonged shutdown were to happen in the Southeast, utilities in the region might have to buy electricity on the wholesale market, and the high costs could be passed on to customers.

"Currently, nuclear power costs between $5 to $7 to produce a megawatt hour," said Daniele Seitz, an energy analyst with New York-based Dahlman Rose & Co. "It would cost 10 times that amount that if you had to buy replacement power -- especially during the summer."