US Electricity Generation is Changing its Fuel Sources, and Water Use Continues to Drop Over Time
US electricity generation—or the way electricity is produced—has changed considerably in recent decades. One major power sector change is the reduction of water withdrawals for power plant cooling, according to newly released US Energy Information Agency (EIA) data. Water withdrawals dropped 10.5 percent from 53.1 trillion gallons in 2019 to 47.5 trillion gallons in 2020, which continues a downward trend.
Many thermoelectric power plants—or power plants that use heat to create steam and turn turbines to generate electricity—require huge volumes of water to cool down equipment and return steam to water. In fact, the thermoelectric power sector withdraws the most water of any other sector in the United States, including agriculture.
The decline in water withdrawals in electricity generation is due to two major factors:
- The increased use of renewable (e.g., wind and solar) and natural gas-fired generation instead of coal-fired generation;
- Less use of once-through cooling technologies at power plants, a technology that uses much more water.
So as electricity generation has moved towards less water-intensive energy sources, the overall water intensity of US power generation has fallen. As EIA notes, the average amount of water withdrawn for each unit of electricity generated has declined from 14,928 gallons per megawatt-hour in 2015 to 11,857 megawatt-hour. This trend is expected to continue as coal-fired power plants are retired because of their harmful pollution and carbon emissions, and more renewables and natural gas-fired power plants replace them.