nuclear-news

Climate change is a threat to nuclear power, with reactors over-heating and high water demand

Amid climate concerns, nuclear plants feel the heat of warming water , Midwest Energy News, Kari Lydersen, 10 Sept 16  Nuclear power proponents say the energy source is crucial to reducing the impact of climate change.

But ironically, “We’ll have to solve global warming if we want to keep using nuclear power,” says Union of Concerned Scientists nuclear safety expert Dave Lochbaum.

That’s because nuclear power plants need large amounts of water for cooling, and overheating can present a major safety risk. As the lakes and rivers that typically supply cooling water become hotter thanks to climate change — and as droughts dry up some water bodies — nuclear power plants face problems, researchers say.

They may need to temporarily shut down or scale back their generation on hot days, which is just when their power is needed most.

This challenge is the focus of ongoing research spearheaded by Oak Ridge National Laboratory and also involves the national laboratories at Sandia, Los Alamos and Argonne. Researchers are modeling predictions about population, temperature, electricity demand, precipitation, land use and other factors to predict the water-related stress on power plants.

“You need to have enough water to cool the power plants and have drinking water and water for agriculture and other industries,” said Melissa Allen, a leader of the team effort and a post-doctoral researcher at Oak Ridge’s Climate Change Science Institute.……..

Hitting limits

The Nuclear Regulatory Commission sets limits on how warm the cooling water can be for each nuclear plant.

The owners of the Millstone plant in Connecticut, Turkey Point in Florida andBraidwood in Illinois have sought and obtained permission from the NRC to increase the maximum temperature limit for their cooling water, Lochbaum noted.

“Millstone uses the Atlantic Ocean, Turkey Point uses a canal system supplemented by water from the Atlantic Ocean, and Braidwood uses river water,” he said. “As global warming increases the temperature of oceans, lakes and rivers, they will hit these limits more often. There are two choices: to reduce power because you can’t exceed those limits. Or do what Turkey, Braidwood and Millstone did — do the homework to get the limit raised.”

Lochbaum analyzes reports from the NRC showing when nuclear plants scale back generation because of warm water.

In June, nuclear plants in Georgia, South Carolina and Pennsylvania scaled back their generation multiple times because of hot temperatures warming their cooling water. The Limerick power plant on the Schuylkill River near Philadelphia has scaled back because of high temperatures frequently over the past decade, according to the reports.

The Dresden and Quad Cities plants in Illinois had to scale back because of high water temperatures multiple times over the past five years. The Duane Arnold plant in Iowa and the Monticello plant in Minnesota also reported scaling back generation because of temperatures.

When cooling water is warmer, greater volumes are needed to cool the reactor. Plants also typically need approval from the NRC to increase the amount of water they use for cooling or to install new technology — like larger pumps — in order to deal with warmer conditions.

Such changes cost money, and scaling back generation means less profit.

“With plants in the Midwest and Northeast facing competition from natural gas and so on, it’s difficult to find the money even if you can make the justification that the money [invested in new cooling systems] would pay off in two years,” said Lochbaum……..http://midwestenergynews.com/2016/09/09/nuclear-plants-feel-the-heat-of-warming-water/

September 10, 2016 - Posted by Christina Macpherson | climate change, USA