Viewpoint: Clean coal and carbon sequestration

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Danvers -
The title sounds great. Our president is talking about it.
Are we doing it? Unfortunately we have no industrial strength examples to cite. In other words we are not yet doing this on a significant scale. We are not even close to doing it.
Why?

Fifty percent of our country’s daily electrical power comes from the combustion of coal. It is our largest source of electricity. We cannot carry on without it. We have no immediate substitute for it. An average quarter trillion watts of output is produced daily from coal consuming 2.5 million tons of coal per day. Most of that coal is composed of carbon, which when burned with air produces about 9 million tons of the greenhouse gas, carbon dioxide (CO2) daily. It has been estimated that about half of the CO2 emitted in the US comes from our coal fired electrical power generating facilities.

This is what the president wants to fix. The question is: “How do we do it and when will it be done?”

There is no such thing as clean coal firing. The coal is initially cleaned up by a gasification procedure that evolves carbon monoxide and hydrogen. It is this gas mixture that is then burned in the power plant producing electricity. All the original carbon is still converted to CO2. This is then captured and eventually sequestered after the gasification and combustion is completed.

Carbon sequestration, also known as geo-sequestration, works this way: You capture CO2 gas at the source before releasing it to the atmosphere, render it into liquid form in some manner and inject it through a pipeline into deep underground holes leading to vast caverns of exhausted petroleum and gas wells. That is the idea. Many questions exist about this process. It requires at least 35 percent more energy and will thus consume coal 35 percent faster while creating 35 percent more greenhouse gas. The economic cost will be enormous, both investment-wise and operational. We do not even know if the sequestered CO2 gas will stay put or eventually leak back out to the atmosphere.
Quoting a department of energy source:

“DOE aims to demonstrate cutting-edge carbon capture and storage technology at multiple commercial-scale integrated gasification combined-cycle plants. Once operational, each demonstration plant will sequester carbon dioxide at a rate of approximately one million tons per year.”

Comparing that statement with reality suggests that each plant will reduce CO2 at the rate of 1 million tons per year versus our current output of 9 million tons per day increasing 35 percent to over 12 million tons per day. Each plant will sequester only 0.02 percent of that number. 50 such plants around the country will accomplish a mere 1 percent of our needs.

Perhaps it is time to get real here. Let’s stop dreaming. We haven’t done it. We may not be able to do it. It isn’t going to happen any time soon. It may not work. This is precisely why we need an integrated approach to solving our energy problems. We need a “here and now” approach with a workable plan, a realistic timetable, and expert leadership.

J. David Cohen lives on Cornell Road in Danvers. He is a retired professional engineer, license 30246, who worked at General Electric Aircraft Engines in Lynn for 45 years.