The Christian Science Monitor
March 23, 2006
Carbon Cloud Over a Green Fuel
An Iowa corn refinery, open since December, uses 300 tons of coal a day to
make ethanol.
By Mark Clayton
Late last year in Goldfield, Iowa, a refinery began pumping out a stream of
ethanol, which supporters call the clean, renewable fuel of the future.
There's just one twist: The plant is burning 300 tons of coal a day to turn
corn into ethanol -- the first US plant of its kind to use coal instead of
cleaner natural gas.
An hour south of Goldfield, another coal-fired ethanol plant is under
construction in Nevada, Iowa. At least three other such refineries are being
built in Montana, North Dakota, and Minnesota.
The trend, which is expected to continue, has left even some ethanol
boosters scratching their heads. Should coal become a standard for 30 to 40
ethanol plants under construction -- and 150 others on the drawing boards --
it would undermine the environmental reasoning for switching to ethanol in
the first place, environmentalists say.
"If the biofuels industry is going to depend on coal, and these conversion
plants release their CO2 to the air, it could undo the global warming
benefits of using ethanol," says David Hawkins, climate director for the
Natural Resources Defense Council in Washington.
The reason for the shift is purely economic. Natural gas has long been the
ethanol industry's fuel of choice. But with natural gas prices soaring, talk
of coal power for new ethanol plants and retrofitting existing refineries
for coal is growing, observers say.
"It just made great economic sense to use coal," says Brad Davis, general
manager of the Gold-Eagle Cooperative that manages the Corn LP plant, which
is farmer and investor owned. "Clean coal" technology, he adds, helps the
Goldfield refinery easily meet pollution limits -- and coal power saves
millions in fuel costs.
Yet even the nearly clear vapor from the refinery contains as much as double
the carbon emissions of a refinery using natural gas, climate experts say.
So if coal-fired ethanol catches on, is it still the "clean, renewable fuel"
the state's favorite son, Sen. Tom Harkin likes to call it?
Such questions arrive amid boom times for America's ethanol industry.
With 97 ethanol refineries pumping out some 4 billion gallons of ethanol,
the industry expects to double over the next six years by adding another 4.4
billion gallons of capacity per year. Tax breaks as well as concerns about
energy security, the environment, and higher gasoline prices are all driving
ethanol forward.
The Goldfield refinery, and the other four coal-fired ethanol plants under
construction are called "dry mill" operations, because of the process they
use. The industry has in the past used coal in a few much larger "wet mill"
operations that produce ethanol and a raft of other products. But dry mills
are the wave of the future, industry experts say. It's their shift to coal
that's causing the concern.
More plants slated for Midwest, West
Scores of these new ethanol refineries are expected to be built across the
Midwest and West by the end of the decade, and many could soon be burning
coal in some form to turn corn into ethanol, industry analysts say.
"It's very likely that coal will be the fuel of choice for most of these new
ethanol plants," says Robert McIlvaine, president of a Northfield, Ill.,
information services company that has compiled a database of nearly 200
ethanol plants now under construction or in planning and development.
If all 190 plants on Mr. McIlvaine's list were built and used coal,
motorists would not reduce America's greenhouse gas emissions, according to
an in-depth analysis of the subject to date by scientists at University of
California at Berkeley, published in Science magazine in January.
Of course, many coal-fired ethanol plants on the drawing board will not be
built, Mr. McIlvaine says. Others in planning for years may still choose
natural gas as fuel to meet air pollution requirements in some states.
Other variations on ethanol-coal are emerging in Goodland, Kan., and
Underwood, N.D., where ethanol plants are being built next to coal-burning
power plants to use waste heat. Efficient, but still coal.
That could spell trouble for ethanol's renewable image.
"If your goal is to reduce costs, then coal is a good idea," says Robert
Brown, director of Iowa State University's office of biorenewables. "If the
goal is a renewable fuel, coal is a bad idea. When greenhouse-gas emissions
go up, environmentalists take note. Then you've got a problem."
Ethanol industry officials say coal-power is just one possibility the
industry is pursuing.
"I think some in the environmental community won't be all that warm and
fuzzy about [coal-fired ethanol]," says Bob Dinneen, president of the
Renewable Fuels Association, the national trade association for the US
fuel-ethanol industry. "It's fair to say there's a trend away from natural
gas, but coal is just one approach. Other technologies are part of the mix,
too."
He cites, for instance, a new ethanol plant in Nebraska strategically
located by a feed lot, using methane from cattle waste to fire ethanol
boilers. Another new plant in Minnesota uses biomass gasification, using
plant material as its fuel.
Coal for now, wood in the future
Coal may end up being merely a transitional fuel in the run-up to cellulosic
ethanol, including switch grass and wood, says another RFA spokesman. While
ethanol production today primarily uses only the corn kernel, cellulosic
will use the whole plant.
Cellulosic ethanol, mentioned by President Bush in his State of the Union
speech, could turn the tide on coal, too, by burning plant dregs in the
boiler with no need for coal at all.
"It's a fact that ethanol is a renewable fuel today and it will stay that
way," says Matt Hartwig, an RFA spokesman. "Any greenhouse-gas emissions
that come out the tailpipe are recycled by the corn plant. I don't expect
the limited number of coal-fired plants out there to change that."
Still, Hawkins insists that if ethanol is made using coal, the carbon
dioxide should be captured and injected into the ground.
"We favor getting ethanol production up," Hawkins says. "But we obviously
favor a cleaner process. We need large cuts in global warming emissions from
transportation. It's not good enough for ethanol to simply be no worse than
gasoline."
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