Retiring fossil fuel power plants will free 2.6 billion cubic meters of fresh water yearly

Transitioning to green energy can increase water availability while reducing carbon emissions

11 December 2022

Fossil fuel-driven power plants will free up billions of gallons of fresh water as they retire, according to new research being reported at AGU’s Fall Meeting on Tuesday, 13 December. Credit: Greg Goebel/flickr

AGU press contact:
Rebecca Dzombak, [email protected] (UTC-5 hours)

Contact for the researchers:
Landon Marston, Virginia Tech, [email protected] (UTC-5 hours)
Emily Grubert, University of Notre Dame, [email protected] (UTC-5 hours)

Like other infrastructure, fossil fuel-based power plants break down over time, and their “retirement age” is predictable. By combining nationwide retirement ages of fossil fuel-based power plants with water use rates and hydrologic modeling, scientists estimate that by the time the last of these plants closes down by around 2065, 2.6 billion cubic meters (92 billion cubic feet) of water per year will be available for other uses.

That’s 687 billion gallons, or enough water to fill over 4.3 trillion 20-ounce water bottles, that fossil fuel-fired power plants are currently using every year.

The new results will be presented at AGU’s annual Fall Meeting on Tuesday, 13 December at 3:55 p.m. CST, at the McCormick Place Convention Center in Chicago and online everywhere.

Many fossil fuel-based power plants use water to cool their systems and scrub pollutants like sulfur dioxide from combustion exhaust. Electricity production currently accounts for approximately 40% of the U.S.’ water withdrawals. While transitioning from fossil fuels to renewable energy has a primary goal of reducing carbon emissions, in the case of retiring fossil fuel power plants, there are significant water benefits, too.

“Climate policy is water policy,” said Emily Grubert, a civil engineer at the University of Notre Dame who co-authored the new research. “The decarbonization of the energy industry can have significant implications on water systems.” It’s just usually an afterthought or added benefit, she said, rather than the main goal.

About two-thirds of the water use reduction could occur as soon as 2035, the target date for total energy sector decarbonization set by the Biden administration. The authors conservatively estimate the last existing fossil fuel-fired power plant will retire in 2065 if they run for about as long as similar plants have in the past, and they are not slated to be replaced.

“This isn’t something that will happen decades from now. It’s in a shorter-term timeframe,” said Landon Marston, a civil engineer at Virginia Tech who will be presenting the research.

Water rights sometimes stay with the site, so net water availability depends on what replaces the fossil fuel-based power plant. When a power plant shuts down — either from policy changes or degradation — the water right isn’t necessarily released back to rivers, surface storage or groundwater. If a more water-intensive use like a nuclear power plant replaces a coal plant, for example, no water may be freed up. But if it’s replaced with something less water-intensive, the benefits can ripple downstream — literally. In many river basins, the models estimate that streamflow could increase by more than 50% by 2050.

“When that power plant goes offline, that water can be made available to downstream folks,” Marston said. “We show that some of these water availability benefits can propagate hundreds of miles downstream, where they can help not only with environmental flows, but also with [human] water needs.”

This effect is especially poignant in the western U.S., which faces worsening droughts. Some urban areas, especially like those in southern Colorado where water availability is a concern, have already been buying up water rights as power plants are decommissioned.


Notes for Journalists:

Landon Marston will present the results of this work at AGU Fall Meeting 2022. For information about Fall Meeting 2022, including the schedule of press events, visit the online Press Center. Neither the presentation nor this press release is under embargo.

Presentation abstract:
H25G-08: Retirement of US Fossil Fuel-Fired Power Plants Increases Water Availability
McCormick Place – E352
Tuesday, December 13
3:55 pm – 4:05 p.m. CT

Related abstracts:
GC26F-06 Comparing the Development of Decarbonized Electricity Systems under Different Environmental Co-priorities: A California Case Study
McCormick Place – S504d
Tuesday, December 13
5:35 – 5:45 p.m. CT

H25G-02 Discovering Human and Earth System Drivers of Global Peak Water Limits
McCormick Place – E352
Tuesday, December 13
2:55 – 3:05 p.m. CT

H45Q-1602 Historical Analysis of Large Reservoir Storage Resilience and Vulnerabilities in CONUS
McCormick Place – Poster Hall A
Thursday, December 15
2:45 – 6:15 p.m. CT

This study is published with open access in the Journal of Hydrology. Neither the paper nor this press release is under embargo. Download a pdf of this article here.

Paper Title:
“Retirement of US Fossil Fuel-Fired Power Plants Will Increase Water Availability”

Paper Authors:

  • Md Abu Bakar Siddik, Virginia Tech, Blacksburg, VA, USA
  • Emily Grubert, University of Notre Dame, Notre Dame, IN, USA
  • Peter Caldwell, USDA Forest Service, Southern Research Station, Center for Integrated Forest Science, Otto, NC, USA
  • Landon T. Marston, (corresponding author), Virginia Tech, Blacksburg, VA, USA