Researchers
from the University of Texas at Austin collected water use data from all 423 of
the state’s power plants. They estimate that the water saved by switching from
coal to natural gas is 25 to 50 times greater than the amount of water used in
fracking to extract the shale gas in the first place. In 2011, the researchers
estimate that Texas would have consumed an extra 32 billion gallons of water if
all its natural gas-fired power plants were instead burning coal. “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,” said Bridget Scanlon, senior research
scientist at the University of Texas’s Bureau of Economic Geology and the lead
author on the study.
The study is a reminder that for all the focus on the water consumed in fracking or by farms through irrigation, one of the single biggest users of water is the power industry itself. Thermoelectric generation—that would be technologies like coal, natural gas and nuclear, which use heat to generate steam—account for approximately 40% of the freshwater withdrawals in the U.S. In arid regions and during droughts—like the historic 2012 drought, which at its height covered up to 65% of the U.S.—water can become so scare that power plants may need to reduce operations or shut down altogether. With population increasing—especially in fecund and popular Texas—and demand rising, the so-called “water-energy nexus” will be a growing challenge for decades to come.
But the huge
amount of water used by power plants tends not to get the kind of attention
that fracking does—probably because fracking, especially on a large scale, is
relatively new, while coal and natural gas plants have been around for decades.
(The Texas State Water Board estimates that
hydrofracking accounts for less than 1% of total water use, while providing more than
10% of the state’s total economic output.) Fracking for oil and gas is also
much more distributed than a centralized power plant is; if you live in Texas,
chances are much better that you live closer to a fracked well than you do a
power plant. Power plants—and the mining of the coal used in many of them—are
out of sight, and thus they’re out of mind.
Still, the
fact remains that Texas was a water-stressed state well before the first gas
well was fracked, and the concentration of fracking in certain areas of the
state can strain
local water supplies. Water use for fracking in Texas is also growing
rapidly, from 36,000 acre-feet in 2008 to 81,500 acre-feet in 2011. That’s
why oil and gas drillers will need to start recycling frac water, or find
substitutes that don’t need water at all, like the liquid petroleum gel made by
the Canadian
company GasFrac. Water is scarce now in Texas and its likely to be even
scarcer in a hotter and more crowded future. Every industry—including oil and
gas—will need to figure out a way to use our most precious resource more
efficiently.
* * *
Bryan Walsh, “Fracking
for Natural Gas May Help Us Save Water,” Time, December 23, 2013
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