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THE REALITY OF CARBON CAPTURE
Coal Bin by Harold Hough Oct/Nov 2009
Everyone is talking about carbon capture – taking carbon dioxide
out of coal powered plant emissions and putting it in the ground. However,
the reality is that carbon capture is already a reality at a 30 year old
power plant in New Haven, West Virginia. The results of this expensive
experiment will help determine if carbon capture is a practical solution
or just another way to make electricity more expensive.
Coal capture is not cheap or simple. The equipment is four stories tall
and bigger than a football field. It has a 150-foot-tall exhaust stack,
ten feet in diameter. Underground there are pipelines that leave the building
and run into saline aquifers two miles underground. Yet, this system only
captures carbon from 20 megawatts of emissions – about 15% of the
plant’s production.
The power plant belongs to American Electric Power (AEP), an electric
utility that is the largest consumer of coal in the United States. "Clearly,
carbon capture and storage is essential for a company like AEP, and I
would argue equally essential for the United States, because you can't
go through the process of prematurely shutting down half the supply base
of the American utility industry," Michael Morris, chief executive
of AEP, told the media.
Capital costs are immense. AEP executives estimate that the cost of carbon
capture for a modest-size coal plant of about 235 megawatts would start
at $700 million. That works out to about $100 for a ton of carbon dioxide,
which is more than the Environmental Protection Agency projects. It’s
also about twice the costs projected by the Massachusetts Institute of
Technology, which estimated carbon capture and storage to cost about $50
to $70 a ton.
The Alstom Process takes the exhaust of the plant after the coal is burned
and "bubbles" it through a solution of chilled ammonia. The
carbon dioxide bonds with the ammonia. Then the carbon dioxide is separated
from the ammonia and compressed for storage.
Once the carbon dioxide is separated, it has to be sequestered. In the
case of the AEP plant, the gas will go into a saline aquifer. In other
parts of the country the carbon will se stored under geologic caps or
sandstone formations thousands of feet underground. Since some plants
aren’t situated near these geological formations, many coal plants
will have to be hooked up to new pipeline networks to carry the carbon
dioxide elsewhere.
All of this takes energy. The Alstom process uses about 15 percent of
the power plant's energy output while other carbon capture processes use
as much as 30 percent. That means that coal powered power plants will
be producing less power at a higher cost per kilowatt. Given projections
that Americans will undergo power brownouts and blackouts in the near
future, this additional electrical demand will just overstress the electrical
power generation system that much more. And, that doesn’t even consider
the fleets of electric cars the Obama Administration wants on the highways.
Ironically, all of this effort and cost will not keep environmentalists
happy. Prominent environmentalists including Dan Becker, director of the
Sierra Club’s Global Warming and Energy Program, believe that the
term clean coal is misleading: "There is no such thing as 'clean
coal' and there never will be. It's an oxymoron". Greenpeace, a foe
of coal-fired power, says that to sequester all the emissions from coal-fired
plants, the volume of carbon dioxide would be equal to 28 million train
cars a day, or a Grand Canyon every 15 days. Then there is the question
of who will monitor the carbon dioxide in these geological formations
for the next few centuries?
In many cases, the opponents of these carbon capture methods have a fiscal
interest in finding other answers. A panel of MIT professors, who are
looking for more R&D money from the government, say that current methods
will not produce clean coal power. They suggested the government investigate
new approaches – approaches that would give MIT an inside track on
new R&D grants. Ernest Moniz, a professor at the Massachusetts Institute
of Technology and a member of President Obama's Council of Advisers on
Science and Technology, said in a report earlier this year. "We urgently
need technology options for these plants and policies that incentivize
implementation."
So, will this experiment work? No one has the answer right now. And,
given the decline in global temperatures, the increasing skepticism about
the manmade global warming theory, the political costs, and the additional
costs that will be imposed on a sick economy, there is a good chance that
the carbon capture requirements found in the Waxman-Markey climate bill
will disappear before they become law. However, with the AEP project,
at least we will have more answers on carbon capture and its practicality
in a few years.
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