Power plants taxing water resources

Nov 16 - McClatchy-Tribune Regional News - S. Heather Duncan The Macon Telegraph, Ga.

Power plants are creating greater stress on the nation's freshwater resources than previously recognized, according to a report released Tuesday by the Energy and Water in a Warming World initiative, a collaboration of scientists.

"Most people are aware of challenges to the water supply in the Southwest. ... But our research also found that this is also potentially a problem in a part of the country where you might not expect it, here in the Southeast U.S., and that much of the stress on watersheds in this region (is) caused by power plants," said John Rogers, a lead researcher on the report and senior analyst at the Union of Concerned Scientists.

Two of the authors of the report "Freshwater Use by U.S. Power Plants: Electricity's Thirst for a Precious Resource" are meeting with academics at Georgia universities and with state environmental regulators this week to discuss their conclusions.

The majority of power plants burn coal or gas, or generate heat using nuclear reactions, to turn water to steam. The steam power runs generators to create electricity.

George Hornberger, who served on the scientific advisory committee for the report, said such plants account for about 40 percent of water withdrawals daily in the U.S. -- as much as farms and much less than drinking water systems.

Nuclear and coal-fired plants put the most stress on freshwater resources, the study found.

The energy sector's water usage during recent droughts, which are expected to increase because of global warming, has caused water shortages or brownouts in the Southeast. The report predicts that those will multiply unless plants are better designed and retrofitted for lower water usage and lower carbon emissions.

The Energy and Water report found that data about power plant water usage was often unreliable. It also highlighted how some power plants put rivers and lakes under stress by dumping water that is 90 degrees or hotter, killing fish.

The report suggested that public utilities commissions should encourage or require power companies to use low-water cooling methods; power companies should try to retrofit existing plants or shutter water guzzlers; and plants should reduce their carbon emissions, because slowing climate change could curb the severity of droughts and prevent water crises.

The study found that Georgia is one of eight states that consume the largest amount of freshwater per unit of electricity generated.

Bill Evans, environmental principal for Georgia Power, said this is probably because the state has many power plants that recirculate their cooling water. Recirculation reduces or eliminates releases of superheated water, but it also consumes more water.

Georgia Power's Plant Scherer outside Macon, one of the largest coal-fired power plants in the country, used 55 million gallons of water a day in 2010 in its recirculating cooling system, Evans said. Scherer consumes about 60 percent of that. The plant releases 22 million gallons a day to the Ocmulgee River to prevent a buildup of concentrated minerals in its equipment, Evans said.

Environmental rules do not require the company to monitor the temperature of that water, he said.

Under-reporting of water use?

The Energy and Water report indicates that many power plants misreport or don't report the water they use. Georgia was listed among states where energy water usage is under-reported.

To reach that conclusion, scientists used federal and other records to identify the fuel type, cooling technology, source of cooling water, and power production at each of the 1,748 water-cooled plants in the country using 2008 data. That was used to calculate the water use for each plant, and those results were compared with what plant operators reported to the U.S. Energy Information Administration.

Georgia's power plants withdraw 1.1 to 2.8 billion gallons a day, Rogers said. Much of that is returned to rivers and lakes, but the report's authors estimate that Georgia plants consume between 153 million and 312 gallons a day.

Evans agreed that reporting could be better. Georgia Power realized after 2005 that its plant engineers were often misreporting consumption use and water temperature, he said. Now, plant environmental managers make those measurements, and the company believes its tracking is more consistent.

April Ingle with the Georgia River Network, which is helping publicize the report, had voiced concerns this year about the need for better information on water use by Georgia energy companies. She noted that Georgia Power was very late to provide water use forecasts to the water planning councils that were creating regional water plans this year. She said the report underscores the need for good information so states can plan ahead.

Georgia has focused on water planning since a federal judge ruled against the state in a lawsuit over Atlanta's use of Lake Lanier water. Although that decision was overturned, the state remains embroiled in wars with its neighbors over water use. A water supply task force convened by Gov. Nathan Deal is scheduled to issue a report today with recommendations about new reservoirs to slake Atlanta's thirst.

The Energy and Water analysis examined the balance of local water supply and demand in more than 2,000 watersheds. Kristen Averyt, a lead researcher for the report, said scientists focused on the 25 watersheds where power plants were causing the greatest degree of stress on water systems. The upper Oconee River system, with four power plants, was among them.

The report mentions that another coal-fired power plant, Plant Washington, is planned for the upper Oconee, with a maximum daily water withdrawal of 16 million gallons a day. All but 1 million to 4 million gallons would be consumed in the plant's recirculating system.

Dean Alford of Power for Georgians, the conglomerate of electric cooperatives planning to build Plant Washington, said the report fails to take into account that most power plants in the Upper Oconee use hydropower.

"And they've never run a ground water/surface water model to simulate the stress," he said. "We did. ... We're very proud of our water plan. We think we're at an eighth of the consumption you'd see for the average thermal plant."

To contact writer S. Heather Duncan, call 744-4225.