March 14, 2007 10:14 AM PDT

MIT: To keep coal, carbon needs to go underground

The Massachusetts Institute of Technology is calling on the U.S. government to commit to large-scale projects to store carbon dioxide underground at coal-fired power plants.

Coal will remain a pervasive source for generating electricity because it is a relatively high-energy, inexpensive fuel available in many parts of the world, MIT said in a study released Wednesday. But burning coal creates a high amount of carbon dioxide, a greenhouse gas that contributes to global warming.

To ensure that coal can be used to address the world's growing energy needs "in an environmentally acceptable manner," the power industry needs to adopt technologies for capturing and storing carbon dioxide underground, the study concluded.

MIT called on the United States, the largest greenhouse gas emitter in the world, to take leadership in these technologies, referred to as carbon capture and sequestration (CCS).

Demonstration of a commercial-scale power plant with integrated carbon capture and sequestration will show that a "practical carbon mitigation control option exists," said John Deutch, an MIT professor of chemistry who co-chaired the interdisciplinary study.

In addition, the authors of the MIT study, titled "The Future of Coal--Options for a Carbon Constrained World," said that carbon-restraining policies should be enacted in the near term to make CCS technologies more attractive.

Without policies that place a price on emitting carbon, the U.S. government could create a "perverse incentive" where utilities build new coal plants without carbon capture technologies before regulations are enacted, MIT said.

The study sets a target of demonstrating that 1 million tons of carbon dioxide per year can be stored in several locations. It calls for 3 sequestration projects in the U.S. and 10 elsewhere in the world, each of which would cost $15 million per year for a 10-year period.

With CCS, MIT forecasts that in 2050 global carbon dioxide emissions from all energy sources would be only slightly higher than today and less than half of the projected "business as usual" scenario, in which fossil fuel use would continue as it is now.

Not picking winners
The most favored CCS technique today is called Integrated Gasification Combined Cycle, which is being tried in new coal plants. But the MIT study's authors said different, viable technologies may emerge.

"The government should provide assistance to several 'first of their kind' coal utilization demonstration plants, but only with carbon capture," according to the study.

Carbon storage projects are under way, but MIT said these do not have the necessary monitoring to ensure that sequestration can be done safely at a large scale for a long period time.

Indeed, even advocates of cleaner sources of energy have significant doubts about carbon capture and sequestration.

Venture capitalist Vinod Khosla, whose firm is investing in a wide range of clean technologies, said Saturday at the MIT Energy 2.0 Conference that he was "suspicious" of sequestration.

The scale of sequestration could cause "unknown changes in soil chemistry," and the cost of these systems are "grossly underestimated," he said. Also, there are concerns that stored carbon dioxide could leak, causing other unforeseen problems.

MIT said the U.S. Department of Energy's current Clean Coal program does not have sufficient funds to meet the study's objectives. It called on the U.S. to undertake a more aggressive research and development effort.

See more CNET content tagged:
carbon, coal, study, capture, plant

10 comments

Join the conversation!
Add your comment
Unforseen problems...
So sequestration of gaseous CO2 could cause "other unforseen
problems"? Like, maybe, sudden death of those into whose
"backyards" the CO2 might suddenly leak? Hopefully, that would be
improbable. However, the "nimby" phenomenon has been
mobilized by less dire prospects, as for example in the case of the
mere possibility of an unsightly wind turbine becoming marginally
visible to well-heeled property owners in various places.
Posted by billmosby (536 comments )
Reply Link Flag
agree
It should not be thought as long term storage but as short term.
The CO2 would be pumped into the ground then processed back
into O2 by whatever means that could be developed. Algae farms
might be a good start.
Posted by twotall610 (53 comments )
Link Flag
Can we break down the CO2?
If the problem with coal burning is the CO2 that is released, what would it take to break down the CO2 into carbon and oxygen? Is the carbon then in solid form? Obviously, it would take energy for this reaction but can't this be obtained from the energy released during combustion? Seems like there should be an easier solution. When they sequester the CO2 underground, don't they store it in underground tanks or something as opposed to pumping it directly underground?
Posted by ebeamsales (36 comments )
Reply Link Flag
Sure you can
Sure you can break the CO2 back into carbon and oxygen. But it would take just as much energy as you got from burning the carbon in the first place. Even more, when you include all the system losses and inefficiencies.

I'm glad people are looking seriously at CO2 sequestration, if only to show how ridiculously impractical it would be, and how easy it is by comparison to bury nuclear waste.
Posted by karn (11 comments )
Link Flag
Give it to the oil companies.
There was an article a few days ago about oil companies extracting more oil from old oil fields by injecting Carbon Dioxide into the deposits. Kill two birds with one stone? ..and for the positive?
Posted by dsf32 (4 comments )
Reply Link Flag
Common practice to inject natural gas
Natural gas is injected back into wells in many places. Although I think there is some well founded criticism of this practice as natural gas is in high demand in the US. I don't know if this would work with CO2.
Posted by richardault (7 comments )
Link Flag
Who's bright idea was it to put CO2 underground , please step forward and receive the dummy award of the year, it would have to be a guy with a degree and bloody no common sense, and on the Coal industry pay roll, do they think we are all stupid out here in the real world, wake up and smell the roses and thrust me mate there are no fairy's at the botton of the garden.
Posted by Hydrogeno2 (1 comment )
Reply Link Flag
 

Join the conversation

Add your comment

The posting of advertisements, profanity, or personal attacks is prohibited. Click here to review our Terms of Use.

What's Hot

Discussions

Shared

RSS Feeds

Add headlines from CNET News to your homepage or feedreader.