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Climate Deal Spurs Hopes of Carbon Plan08/15 06:06
GILLETTE, Wyo. (AP) -- The rolling prairie lands of northeastern Wyoming
have been a paradise of lush, knee-deep grass for sheep, cattle and pronghorn
antelope this summer.
But it's a different green -- greener energy -- that geologist Fred
McLaughlin seeks as he drills nearly two miles (3.2 kilometers) into the
ground, far deeper than the thick coal seams that make this the top coal-mining
region in the United States. McLaughlin and his University of Wyoming
colleagues are studying whether tiny spaces in rock deep underground can
permanently store vast volumes of greenhouse gas emitted by a coal-fired power
plant.
This is the concept known as carbon storage, long touted as an answer to
global warming that preserves the energy industry's burning of fossil fuels to
generate electricity.
So far, removing carbon dioxide from power plant smokestacks and pumping it
underground hasn't been feasible without higher electricity bills to cover the
technique's huge costs. But with a $2.5 billion infusion from Congress last
year and now bigger tax incentives through the Inflation Reduction Act passed
by Congress on Friday, researchers and industry continue to try.
One goal of McLaughlin's project is to preserve the lifespan of a relatively
new coal-fired power plant, Dry Fork Station, run by Basin Electric Power
Cooperative. State officials hope it will do the same for the whole beleaguered
coal industry that still underpins Wyoming's economy. The state produces about
40% of the nation's coal but declining production and a series of layoffs and
bankruptcies have beset the Gillette area's vast, open-pit coal mines over the
past decade.
While the economics of carbon storage remain uncertain at best, McLaughlin
and others are confident in the technology.
"The geology exists," McLaughlin said. "It is a resource we're looking for
-- and the resource is pore space."
HOW IT WORKS
By pore space, McLaughlin doesn't mean skin care but microscopic spaces
between grains of sandstone deep underground. Countless such spaces add up:
Enough, he hopes, to hold 55 million tons (50 million metric tons) of carbon
dioxide over 30 years.
McLaughlin and his team used the same drill rigs as the oil industry to bore
their two wells almost 10,000 feet (3,000 meters), taking core samples from
nine geological formations in the process. The researchers will study how
injection at one well, using saltwater as a stand-in for liquid carbon dioxide,
could affect fluid behavior at the other.
"It's basically like a call and response, if you want to think of it that
way," McLaughlin said. "We can ground truth our simulations."
McLaughlin's team also does a lot of lab work on carbon sequestration back
at the University of Wyoming School of Energy Resources in Laramie, studying on
a microscopic scale how much carbon dioxide different sandstone layers can
hold. They model on computers how much carbon dioxide, well by well, could be
pumped underground north of Gillette.
Eventually they want to advance to carbon dioxide captured from the smoke
plume at nearby Dry Fork Station, using a technique developed by
California-based Membrane Technology and Research, Inc.
WYOMING'S CARBON DREAMS
With an eye toward carbon storage, Wyoming in 2020 became one of just two
states, along with North Dakota, to take over from the U.S. Environmental
Protection Agency primary authority to issue the kind of permit McLaughlin and
his team will need to pump large volumes of carbon dioxide, pressurized into a
high density "supercritical" state, underground.
Besides the permit, the geologists will also need more funding. The U.S.
Department of Energy Carbon Storage Assurance Facility Enterprise (CarbonSAFE)
program is funding 24 carbon capture and storage projects nationwide, and this
is one of the furthest along.
Such projects were likely already eligible for some of the roughly $2.5
billion in last year's infrastructure bill. Now the new Inflation Reduction Act
will boost the "45Q" tax credit for electricity producers who sequester their
carbon from $50 to $85 per ton.
Pumping carbon dioxide underground is nothing new. For decades, the oil and
gas industry has used carbon dioxide, after it's separated from the methane
sold for fueling stoves and furnaces, to recharge aging oil fields.
UNTIL NOW, FAILED EXPERIMENTS
Critics, however, point out the process is expensive to use at power plants
and provides a lifeline of sorts to the coal, oil and natural gas industries
when the world, in their view, should stop using fossil fuels altogether.
To date, only one commercially-operational, large-scale project in the U.S.
has pumped carbon dioxide from a power plant underground. But to defray costs,
NRG Energy's Petra Nova coal-fired power plant outside Houston sold its carbon
dioxide to increase local oil production.
After three years in operation, Petra Nova closed in 2020, when low oil
prices made using the gas to recharge a nearby oil field unprofitable.
In December, a U.S. Government Accountability Office review found that Petra
Nova was the only one of eight carbon capture and storage projects at
coal-fired plants to actually go into operation, after getting $684 million in
Department of Energy funding since 2009.
Some communities that have dealt for years with industrial air pollution
also worry that companies will use promises of carbon storage as a way to
expand.
For Massachusetts Institute of Technology research engineer Howard Herzog, a
carbon capture and storage pioneer, the question isn't whether the technique is
technically feasible at scale. He's certain that it is. But whether it can be
economically feasible is a different matter.
"People are starting to take it more seriously even though fundamentally
changing our energy systems is not an easy task," Herzog said. "It's not
something you do in the short term. You've got to really set the policy in
place and we still haven't really done that."
It may be expensive, said Herzog. But doing nothing when it comes to
climate, "may be much more expensive."
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