Contrary to the conventional beliefs of many environmentalists, new research shows that hydraulic fracturing has at least one major (and ironic) environmental benefit: saving water.

Most Americans are generally unfamiliar with fracing, but it is arguably an issue of critical importance—not only with respect to the environment but also in foreign policy and the economy.

The debate is typically framed this way: Those who care more about the environment typically oppose fracing, and those who care more about US energy independence and domestic economic opportunities are usually fracing proponents.

However, a new study published in late December by the University of Texas at Austin (UT-Austin) disrupts that dichotomy. At a time when climate-change scientists are increasingly concerned about the effects of drought, the UT-Austin research shows that the water-intensive fracing method of extracting natural gas actually saves water in the aggregate.

Texas experienced the most extreme drought on record in 2011, with up to 100 days of triple-digit temperatures resulting in record electricity demand and historically low reservoir levels.

Electricity produced using natural gas combustion turbines and natural gas combined-cycle generators requires roughly 30% of the water needed by coal-power plants. The study estimates that the amount of water saved by shifting a power plant from coal to natural gas is up to 50 times the amount of water lost in fracing to extract the natural gas from underground shale formations.

UT-Austin researchers estimate that for every gallon of water used to frac for natural gas, Texas saved 33 gallons of water by using that gas for electricity generation rather than producing the same amount of power with coal.

“During the 2011 drought, if Texas' natural gas-fired power plants had generated electricity with coal, the state would have consumed an additional 32 billion gallons of water, or enough to supply about 870,000 people with water, accounting for water used for fracing,” according to the study.

The analysis quantified water and electricity demand and supply for all 423 of the state's power plants during the drought relative to 2010 (baseline). In 2011, researchers estimated that Texas would have consumed an extra 32 billion gallons of water if all its natural gas-fired power plants were instead burning coal.

“Drought raised electricity demands/generation by 6%—increasing water demands/ con - sumption for electricity by 9%,” according to the study. “Reductions in monitored reservoir storage less than 50% of capacity in 2011 would suggest drought vulnerability, but data show that the power plants were flexible enough at the plant level to adapt by switching to less water-intensive technologies.

“Natural gas—now approximately 50% of power generation in Texas—enhances drought resilience by increasing the flexibility of power-plant generators, including gas-combustion turbines to complement increasing wind generation and combined-cycle generators with approximately 30% of cooling-water requirements of traditional steam-turbine plants,” researchers says.“These reductions in water use are projected to continue to 2030 with increased use of natural gas and renewables.”

Commenting on the new report, Bridget Scanlon, senior research scientist at UT's Bureau of Economic Geology and lead author of the study, says, “The bottom line is that hydraulic fracturing, by boosting natural gas production and moving the state from water-intensive coal technologies, makes our electric-power system more drought-resilient.”

—Kristie Sotolongo

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