Natural Gas Use in Power Generation Saves Water and Reduces Drought Vulnerability

Dec. 19, 2013

AUSTIN, Texas — Water SavingsA new study finds that in Texas, the U.S. state that annually generates the most electricity, using natural gas for electricity generation is saving water and making the state less vulnerable to drought.

Even though exploration for natural gas requires significant water consumption in Texas, the new consumption is easily offset by the overall water efficiencies of electricity generation from natural gas. The researchers estimate that water saved by shifting a power plant from coal to natural gas is 25 to 50 times as great as the amount of water used in hydraulic fracturing to extract the natural gas. Natural gas also enhances drought resilience by providing so-called peaking plants to complement increasing wind generation, which doesn’t consume water.

The results of The University of Texas at Austin study are published this week in the journal Environmental Research Letters.

Environmentalists and others have raised concerns about the amount of water that is consumed in producing natural gas. In Texas, concerns are heightened because the third year of a devastating drought grinds on. Because most electric power plants rely on water for cooling, the electric power supply might be particularly vulnerable to drought.

“The bottom line is that boosting natural gas production and using more natural gas in power generation makes our electric grid more drought resilient,” says Bridget Scanlon, senior research scientist at the university’s Bureau of Economic Geology, who led the study.

To study the drought resilience of Texas power plants, Scanlon and her colleagues collected water use data for all 423 of the state’s power plants from the Energy Information Administration and from state agencies including the Texas Commission on Environmental Quality and the Texas Water Development Board, as well as other data.

Since the 1990s, the primary type of power plant built in Texas has been the natural gas combined cycle (NGCC) plant with cooling towers, which uses fuel and cooling water more efficiently than older steam turbine technologies. About a third of Texas power plants are NGCC. NGCC plants consume about a third as much water as coal steam turbine (CST) plants.

The other major type of natural gas plant in the state is a natural gas combustion turbine (NGCT) plant. NGCT plants can also help reduce the state’s water consumption for electricity generation by providing “peaking power” to support expansion of wind energy. Wind turbines don’t require water for cooling; yet wind doesn’t always blow when you need electricity. NGCT generators can be brought online in a matter of seconds to smooth out swings in electricity demand. By combining NGCT generation with wind generation, total water use can be lowered even further compared with coal-fired power generation.

The study focused exclusively on Texas, but the authors believe the results should be applicable to other regions of the U.S., where water consumption rates for the key technologies evaluated are generally similar.

The Electric Reliability Council of Texas, manager of the state’s electricity grid, projects that if current market conditions continue through 2029, 65 percent of new power generation in the state will come from NGCC plants and 35 percent from natural gas combustion turbine plants, which use no water for cooling, but are less energy efficient than NGCC plants.

“Statewide, we’re on track to continue reducing our water intensity of electricity generation,” says Scanlon.

Scanlon’s co-authors at the Bureau of Economic Geology are Ian Duncan, research scientist, and Robert Reedy, research scientist associate. The bureau is a research unit in the Jackson School of Geosciences at The University of Texas at Austin.

The Jackson School helped fund the research along with the State of Texas Advanced Resource Recovery (STARR) program, a state-funded program managed by the Bureau of Economic Geology.

Access the study “Drought and the water–energy nexus in Texas” at:

The University of Texas at Austin is committed to full transparency and disclosure. Bridget Scanlon has received research funding in the past from various governmental, nonprofit and private organizations such as the Texas Commission on Environmental Quality, NASA, the National Science Foundation and Shell International Exploration and Production Inc. Ian Duncan has received research funding in the past from various governmental, nonprofit and private organizations such as the U.S. Department of Energy, the Sloan Foundation and Shell International Exploration and Production Inc. Robert Reedy has received research funding in the past from various governmental, nonprofit and private organizations such as the Texas Commission on Environmental Quality and Shell International Exploration and Production Inc.

For more information, contact: Marc Airhart, College of Natural Sciences, 512 232 1066.

8 Comments to "Natural Gas Use in Power Generation Saves Water and Reduces Drought Vulnerability"

1.  Álvaro said on Dec. 23, 2013

Could you please provide me via mail the report ?
Thank you

2.  Don (Maintenance Management) said on Dec. 26, 2013

Good example of why people should always look at the big picture and the long term. Good thing UT did.

3.  Ken Dykes said on Dec. 28, 2013

If the amount of water on the planet is finite, it is not consumed, just borrowed. There is no loss. In a steam generated power plant, water is in a closed system. There is no loss. Water used for cooling in condensers is just borrowed from a large source, ie: a river, and returned to that source to continue on its journey to sea level. Any water in a gaseous state from the power station is emitted into the atmosphere where it rejoins the hydrologic cycle. So water is not lost (consumed). Water used in fracturing ends up in ground water systems, hence not consumed either. What am I missing?

4.  T Murchison said on Dec. 30, 2013

It's no surprise to me that fracturing has the added benefit of saving water, but let's face it, our current energy policy while improving is still hard on the environment. Even wind and solar have their negative consequences.

As long as people stay informed, our academic institutions conduct research like what was done in Texas, and we keep looking for new and better sources of energy or ways to optimize our existing sources, then there's reason to be optimistic about our future.

5.  Sandra said on Jan. 2, 2014

Could you please provide me via mail the report ?

6.  Ray Devine said on Jan. 2, 2014

isn't water vapor a by product of combustion of CH4 (methane) as well?

7.  George King said on Jan. 6, 2014

Good study, but not the whole picture. Water used in fracturing is increasingly from salt water sources, recycled from oil & gas production operations or frac flowback, thus the drain on fresh water supplies is declining. Also - burning CH4 (with its four molecules of hydrogen) generates H2O - each bcf of methane gas generates about 11 million gallons of water - thus it easly offsets the water used in fracturing.

8.  Jeff said on Jan. 7, 2014

Ken: True, the water isn't technically "lost." What is being lost is cheap, clean, readily-available fresh water.

Open-loop cooling, where you borrow cool water from a lake or river, use it to cool your plant, then return the warm water to its source is limited either by the reservoir's ability to absorb heat or thermal discharge limits imposed for ecological reasons. (That's a big issue at the Vermont Yankee nuclear plant, for example.)

Closed-loop cooling, where you cool and reuse cooling water with a cooling tower create water vapor. Yes, it renters the hydro cycle, but it's no longer in the form or location that makes it useful.

Water used in fracturing doesn't end up in ground water. In fact, it's so full of sand and chemicals that you don't want it anywhere near your ground water. Contamination from frac water is one of the issues used in arguments against fracing. The rest of the argument is that fracturing changes large amounts of that "cheap, clean, readily-available fresh water" into contaminated frac fluid. But as George points out, technology is reducing the amount of fresh water required.

Here's a good article on the relative amounts of water used in different energy areas: