It suddenly became apparent, just a couple of days ago when President Trump was ranting and raving at a political rally, that the man does not know what clean coal is.
This is a concern because his entire energy policy stems from the assumption that we can mine lots of coal in West Virginia and use that for energy, that this is OK because it will be clean coal.
The term clean coal has been used in three ways, but really, is correctly used in only one way (number 2 of the three below), and when used that way, it is still bogus.
1) The term clean coal, or phrases very close to it, have been used by the energy industry to refer to their cleaning up of coal plants to have them put fewer nasty particulates and chemicals into the air. Clean plants produce clean effluence while burning coal. This is nice and all, but it has nothing to do with the fundamental problem that burning coal is a major contribution to global warming, because when you burn coal you take Carbon that is attached mainly to other Carbon atoms in solid form, and combine it with Oxygen, to make heat and CO2. The CO2 is the greenhouse gas.
2) The term clean coal refers to burning coal and somehow making the CO2 not go into the atmosphere. A method that makes the Carbon not become CO2 is essentially impossible because it is the oxidation of the Carbon that is the energy production process. You can not turn coal into heat energy without making CO2. It. Is. Not. Possible. But, some say it is possible to make the CO2 go away or not be a problem in some other way. If we were talking about a small amount of CO2, that might be possible. We could store it underground or something (never mind that this takes energy too). But for burning a lot of coal, for keeping coal as a major part of our energy policy, we simply can’t do that. You cant store away a gazillaton of a gas every year and expect it to stay stored.
3) This is the newest definition. This is Trump’s definition. You dig the coal up, then you wash it so it is clean. Then you burn it and everything is fine.
By the way, the photo above is of the harvesting of sea coal in Hartepool. That, apparently, was a thing.