Release Date: December 15, 2006
|DOE Estimates Future Freshwater Needs to Meet Thermoelectric Power Demand
New Analysis Examines Regional Differences in Freshwater Needs, Provides Baseline for Measuring Research Progress
WASHINGTON, DC - In support of an emerging energy-water research program, the U.S. Department of Energy's National Energy Technology Laboratory (NETL) has updated its groundbreaking 2004 study estimating future freshwater requirements for the U.S. thermoelectric generation sector. Bringing a much-needed regional focus, the new report, Estimating Freshwater Needs to Meet Future Thermoelectric Generation Requirements, identifies a dichotomy between national and local freshwater needs and pinpoints where critical water issues could develop.
The Energy Department will use results from the new analysis to better understand the regional impacts of new thermoelectric power on U.S. water resources. The results will also allow researchers to measure progress in preserving the nation's freshwater resources by comparing reductions in withdrawal and consumption against the base projections outlined in the report.
Thermoelectric power plants are a major competitor for freshwater and will remain so in the future. These plants, which employ steam turbines fueled by coal, oil, natural gas and nuclear energy sources to generate electricity, require significant quantities of water. On average, thermoelectric power plants operating today withdraw approximately 25 gallons of water for each kilowatt of electricity generated, primarily for cooling.
The intimate link between water and thermoelectric generation has been driven home by recent accounts of new power projects being shut down because they cannot secure needed water permits. The increasing competition between power generation and other water-use sectors, such as agricultural, industrial, domestic, and in-stream use, will need to be addressed if the United States is to maintain economic growth and current standards of living.
The new study, conducted by the Energy Department's National Energy Technology Laboratory (NETL), uses various scenarios to estimate freshwater withdrawal (water removed from the ground or diverted from a surface-water source for use) and consumption (water that is not available for immediate reuse because it has evaporated, transpired, or been incorporated into products) for thermoelectric generation. The NETL analysis is based on the Energy Information Agency's Annual Energy Outlook 2006, which forecasts U.S. energy demand through 2030.
On a national scale, freshwater withdrawal is projected to decrease anywhere from 1 to 31 percent between now and 2030, while consumption will increase from 21 to 48 percent over the same period. However, a comparison of NETL's 2004 water-needs analysis and the new study revealed significant regional differences in projected electricity and freshwater demand and availability, particularly in arid areas like Nevada and Arizona.
In one of the future cooling-system scenario presented in the report, national water withdrawals fall by 8.6 percent and water consumption rises by 32.3 percent between 2005 and 2030, but regional data shows withdrawals ranging from a 25 percent increase in Florida to a 30 percent decline in Texas. Consumption rates in this scenario increase in all regions, with California topping the bill with 352 percent.
As the analysis illustrates, water is a significant emerging factor in economic development, especially at local and regional levels. The report emphasizes that water resources must be included in planning efforts to ensure that water supplies are not only currently available, but also on hand for all future water-use sectors over the long term, including thermoelectric generation.
NETL is carrying out an integrated research program to help thermoelectric power plants better manage their freshwater use. The program includes research and development directed at advanced cooling, water recovery and reuse, use of non-traditional (impaired) water, and wastewater treatment technologies. The program goal is to ensure that, by 2015, technologies are available for initial commercial deployment that can reduce power plant freshwater withdrawal and consumption and minimize the impacts of power plant operation on water quality.
The research program falls under NETL's Innovations for Existing Plants Program which aims to enhance the efficiency and environmental performance of the existing fleet of coal-fired power plants and apply novel concepts to advanced power systems.