Power plants that generate steam to make electricity—all coal and nuclear plants, many natural gas plants, and some renewable energy facilities—typically use water to cool and re-condense that steam for reuse, and often in large quantities (DOE 2006). Such thermoelectric power plants are responsible for the largest share of freshwater withdrawals in the United States: more than 40 percent in 2005 (Kenny et al. 2009). They are also one of the largest non-agricultural consumers of such water, through the evaporation that serves to remove the excess heat during the cooling process (Solley, Pierce, and Perlman 1998).¹

Power plants...

Energy-water collisions are happening now. Because of its outsized water dependence, the U.S. electricity sector is running into and exacerbating growing water constraints in many parts of the country. The reliance of many power plants on lakes, rivers, and groundwater for cooling water can exert heavy pressure on those sources and leave the plants vulnerable to energy-water collisions, particularly during drought or hot weather. When plants cannot get enough cooling water, for example, they must cut back or completely shut down their generators, as happened repeatedly in 2012 at plants around the country.

As the contest for water heats up,...

The U.S. power sector is undergoing rapid transformation. The biggest shift in capacity and fuel in half a century is under way, as electricity from coal plants shrinks and power from natural gas and renewables grows. Several factors are spurring this transition to a new mix of technologies and fuels. They include the advanced age of many power plants, expanding domestic gas supplies and low natural gas prices, state renewable energy and efficiency policies, new federal air-quality regulations, and the relative costs and risks of coal-fired and nuclear energy.

This presents an opportunity we cannot afford to miss. Decisions about...

Business as usual in the power sector would fail to reduce carbon emissions, and would not tap opportunities to safeguard water. Because such a pathway for meeting future electricity needs would not cut carbon emissions, it would do nothing to address the impact of climate change on water. Changes in the power plant fleet would mean that water withdrawals by power plants would drop, yet plants’ water consumption would not decline for decades, and then only slowly. The harmful effects of power plants on water temperatures in lakes and rivers might continue unabated, or even worsen. Greater extraction of fossil...

We can make decisions now to reduce water and climate risk. Fuel and technology options already available mean we can design an electricity system with far lower water and climate risks. These include prioritizing low-carbon, water-smart options such as renewable energy and energy efficiency, upgrading power plant cooling systems with those that ease water stress, and matching cooling needs with the most appropriate water sources.

Electricity decisions should meet water-smart criteria. These criteria can point decision makers to options that reduce carbon emissions and exposure to water-related risks, make sense locally, and are cost-effective.

Actors in many sectors have essential...