Researchers at Harvard University found that natural gas production requires less water than is required for producing the same amount of energy from coal, uranium, and biofuels.
But that’s only the production of the energy. It also makes sense to look at water usage over the full life cycle of a fuel when used for electrical generation. In this regard, the Harvard researchers also noted that “the increased role of shale gas in the U.S. energy sector could result in reduced water consumption” overall because of shifting from coal to natural gas for power generation.
That prediction, from 2010, turned out to be right on the money.
Water savings from shifting fuels
According to a new study published last month by researchers at the University of Texas, “The 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.”
That’s because generating power using natural-gas-fired turbines or natural gas combined-cycle generators uses roughly 30 percent of the water needed for coal-fired power plants.
Those efficiencies amount to big savings that far outweigh the amounts of water being used to support hydraulic fracturing.
All told, according to the study, for every gallon of water used to produce natural gas through hydraulic fracturing in Texas, the state saved 33 gallons of water by generating electricity with gas instead of coal.
Applications for the entire country
These research results are applicable to other regions of the country since water consumption rates for the power sector are comparable. For example, a peer-reviewed life-cycle analysis of natural gas production in Pennsylvania’s Marcellus Shale that was conducted by two ExxonMobil researchers reached very similar conclusions.
Of course, there are legitimate concerns about water use and hydraulic fracturing. For instance, the UT study notes that “heavy use of fracking in water-challenged areas could still strain local supplies, especially since the downstream benefits might well be realized elsewhere.”
But that’s no different from other energy forms. Solar, for instance, also has significant water use associated with electricity generation.
A story in The New York Times focused on water use at two planned solar installations in California that would use more than 1.2 billion gallons of water a year, according to applications filed with the California Energy Commission.
All of this reinforces the need for state and local officials to work with residents, industry, and other stakeholders to come up with workable solutions when varied interests compete.