U.S. power producers must reduce their dependence on water or they may be forced to lower output as drought and other extreme weather events curtail their access to water supplies, researchers said today.
Power plants throughout the U.S. “repeatedly” had to reduce output or even shut down completely last year for want of cooling water, and the conflict between the growing need for electricity and the increasing demands on the water supply is only becoming more pronounced, according to a report from the Union of Concerned Scientists.
About 40 percent of the U.S. supply of fresh water goes to power plants that convert steam into power, the Cambridge, Massachusetts-based group said. That comprises all coal and nuclear facilities and some fueled by natural gas and renewable sources. As the utility industry seeks to reduce carbon emissions by replacing aging generating stations, it should also consider water consumption.
“We did set electricity and water on a collision course years ago, but we have options,” John Rogers, a senior energy analyst at the Union of Concerned Scientists, said on a conference call today. “We have the possibility and real need to build a power system that’s more equipped for the changing water landscape.”
Two technologies aimed at reducing carbon emissions, nuclear power and carbon capture and storage for coal plants, require substantial water resources. “That could worsen rather than lessen the sector’s effects on water,” according to the report.
Existing facilities also may adjust the ways they use water. The Palo Verde nuclear plant outside Phoenix now uses wastewater for cooling, saving 11 billion gallons (42 billion liters) of fresh water annually.