A Rose By Any Other Name...

This is an excerpt from a Christian Science Monitor article published during the 2008 presidential campaign season:

But what exactly is clean coal? And why are all the candidates so quick to proclaim their support for it?

To answer both those questions: It’s a vague concept with positive connotations. And it’s a vague concept with positive connotations.

http://features.csmonitor.com/environment/2008/10/17/what-is-clean-coal-anyway/

The term is vague and that results in a lot of banter about the term rather than debating the pros and cons of the technology. The term always refers to the burning of the coal because the mining techniques remain the same and are definitely dirty.

“Clean Coal” can mean a number of quite different things. On the minimalist side, some use the term to describe one or more simple coal washing techniques. The “Clean Coal” method that is relevant to today’s concerns about climate change involves the IGCC process and similar processes.

Integrated Gasification Combined Cycle (IGCC) plants operate as follows:

• Coal is reacted with oxygen and steam to produce a synthetic gas (syngas).


• The syngas is cleaned to remove pollutants including sulfur.


• A gas turbine burns the syngas to produce electricity.


• “Waste” heat from the gas turbine and gasification reaction is used to create steam for a steam turbine which produces additional electricity.

IGCC plants produce about half the currently-regulated pollutants (carbon dioxide is not regulated) compared to conventional pulverized coal power plants. In the cleaning step, much of the carbon can also be removed but I suspect that would severely reduce the efficiency of the plant.

The claim to fame of the IGCC process is that carbon emissions can be captured more feasibly than in a pulverized coal power plant. Then the question is: what do you do with the captured carbon dioxide? Petroleum producers have long been injecting carbon dioxide into depleted oil wells to wring out the last bit of oil. However the feasibility of storing carbon dioxide on a massive scale in geological formations remains to be proven. Will it leak out? Will it make the ground unstable?

One of the two operating IGCC power plants in the U.S. is in Polk County, Florida (the other is the Wabash River Plant near Terre Haute, Indiana). The state of Florida will not indemnify the Polk plant for carbon dioxide storage underground, i.e. Polk will not assume the risk of their stored carbon dioxide leaking into someone’s basement and asphyxiating them.

The term “Clean Coal” is overused lately given the scarcity of operational plants. One organization http://www.thisisreality.org/ has been pointing out this fact in a clever cable TV spot. It shows a man in a hardhat providing a “tour” of a “Clean Coal” plant; all that is shown is a wasteland.