Tired of hearing about "Clean Coal"?
The January 2016 issue of Scientific American magazine contained an article titled The Carbon Capture fallacy. A subtitle stated that all credible plans for reducing global warming relied upon carbon capture and sequestration (CCS) playing a major role, which was deemed to be unlikely. The article generally is based on an analysis of the Kemper County Energy Facility "clean coal" plant under construction by Mississippi Power. The plant converts coal into a cleaner burning gas and then tries to trap the CO2 combustion byproduct. It involves 40,000 tons of steel and 172 miles of pipes,in addition to other hardware and site delvelopment. It is more or less state of the art.
A diagram of the process can be found on line here: Diagram
The whole article is on line if you wish to pay about 9 bucks for it, or you can get the magazine at your local library, assuming that you still have one.
The process relies upon 2 gasifiers weighing over 2,500 tons each to convert lignite into a combustable fuel gas. The CO2 is then stripped and accumulted for disposition. The article's author is not overly enthusiastic and recites a list of some of the 33 failed projects, that generally failed due to unsustainable costs. Rather than attempting one of the proposed methods of sequestration itself, Kemperer intends to sell the CO2 to oil companies for use in oil extraction. Roughly 1/3 of the CO2 injected into injection wells stays down there, and the rest is mixed with newly added CO2 and reused for further injection. Both Kemperer and a CCS project in Saskatchewan incurred costs of about $!0,000 per kilowatt of generating capacity for the carbon capture equipment, which is estimated to increase consumer bills about 4 cents per kilowatt-hour. This is allegedly a 33% increase in average consumer prices.
Sequestration, the "S" in CCS is not only uncertain as to permanence, but not that easy for most plants. Not all plants are near underground geologic features of a type that could theoretically be used for CO2 storage. This means that there will be transportation costs and risks. Similarly, not all are near enough to major oil fields to sell the CO2 to oil companies without major transportation costs. From a purely greenhouse gas standpoint, Kemperer's approach trades sequestration of the CO2 for petroleum, the combustion of which will generate more CO2.
In the end, once operating as designed and expected, Kemperer will only capture 65% of the CO2 it produces. It will still emit about the same amount of CO2 per kilowatt into the atmosphere as a natural gas plant, and at a greater cost. It is even less competitive with renewables in many parts of the country. The author's conclusion is that coal + CCS is already an expensive luxury, so we must either forego coal or pay a serious premium for power if we wish to start reducing the amount of CO2 we are dumping into the atmosphere.
Crossposted from caucus 99%