Small modular reactors (SMRs) are nuclear generating units that are about the size of railroad cars and provide about one-tenth to one-fourth the power of full-size reactors. As a result, they...
Utilities that have new nuclear plants on the drawing board are involved in a host of strategies designed to address water issues.
For some, these focus primarily on location. For others, technology is a key.
Entergy Nuclear is one utility largely relying on location to deal with water issues. As the second-largest nuclear generator in the United States, Entergy Nuclear operates 12 nuclear plants at 10 sites in eight states. The company filed an application in early 2008 potentially to build a second reactor at its Grand Gulf site in Port Gibson, Miss. It also will file another application by the end of the year for a second reactor at its River Bend Station in Louisiana. “We don’t anticipate water problems with either of these plants,” says Entergy spokesman Mike Bolling. “Both of them are on the Mississippi River.”
Southern Nuclear also is using location as a strategy. The utility currently has three nuclear plants: Farley (Dothan, Ala.), Hatch (Baxley, Ga.), and Vogtle (Waynesboro, Ga.). “We are discussing how the addition of new units at Plant Vogtle would affect water use,” says Beth Thomas, a spokesperson for Southern Nuclear. “We have two units at Plant Vogtle. They use about 1 percent of the average annual flow of the Savannah River.” If Southern builds two additional units there, according to Thomas, that would increase water usage to about 2 percent.
Amoi Geter, also a spokesperson for Southern Nuclear, says Southern Company as a whole stays engaged with state and local water-resource planning authorities. “For example, at Plant Farley, we work with entities such as the Army Corps of Engineers, which regulates water flow in that area,” she says. “As a result, even during the extreme drought last year, we were not impacted in any way. We were able to maintain full operations.”
Dominion, which currently operates four nuclear stations, plans to build more. For at least one of the locations, technology is expected to play an important role. Before building the two-unit North Anna Power Station in the late 1970s, near Richmond, Virginia, Dominion built a 9,600-acre lake by damming a river and creating a 3,400-acre waste heat treatment facility to provide cooling water for the station. In late 2007, Dominion filed an application with the NRC for a license to build and operate a new 1,500-MW reactor at North Anna. Because the original lake and treatment facility were built to support four, 800-MW units, Dominion doesn’t anticipate a problem bringing on-line the third unit.
Still, Dominion is using the opportunity to consider water-conservation strategies, as evidenced by its commitment to install Unit 3 with cooling towers. According to John Waddill, lead civil mechanical engineer, Dominion’s initial plans considered a once-through cooling unit that would have consumed 28 cubic feet of water a second. “If we went with a normal mechanical draft cooling tower, we would actually end up using more water than the once-through,” he says. Ultimately Dominion decided to use a hybrid system that uses evaporation for heat