In a recent article in Scientific American, reporter David Biello summarizes the current state of carbon-capture technology, and it's not good. If a negative view of carbon capture appeared in some obscure climate-change-denier publication, it could be dismissed as biased reporting. But the elite-establishment Scientific American has been in the forefront of the anti-climate-change parade, and so for such an organ to publish such bad news means that we would do well to take it seriously.
The basic problem is that capturing a gas like carbon dioxide, compressing it, and injecting it deep enough underground where it won't come out again for a few thousand years is not cheap. And the worst fossil-fuel offenders—coal-fired power plants—make literally tons of the stuff every second. It would be hard enough to transport and bury tons of solid material (and coal ash is a nasty enough waste product), but we're talking about tons of a gas, not a solid. Just the energy required to compress it is huge, and the auxiliary operations (cleaning the gas, drilling wells, finding suitable geologic structures to hold it underground) add millions to billions to the cost of an average-size coal-fired plant. Worst of all, the goal for which all this effort is expended—slowing carbon-dioxide emissions—is a politically-tinged goal whose merit is doubted by many, and which is being ignored wholesale by some of the world's worst offenders in this regard, namely China and India.
However, shrinking the U. S. carbon footprint is regarded by many as a noble cause, and a few years ago Mississippi Power got on the bandwagon by designing a new lignite-burning power plant to capture its own carbon-dioxide emissions and send them into a nearby oil field, whereupon they expel oil that is, uh, eventually burned to make more carbon dioxide. Here is the first irony. Evidently, one of the few large-scale customers for large quantities of carbon dioxide are oil companies, who send it underground (good) to make more oil come to the surface (not so good).
The second irony is an economic one. It is the punishment meted out by economics to the few good corporate citizens in a situation where most citizens are not being so good.
Currently in the U. S., there is no uniform, rational, and legally enacted set of rules regarding carbon-capture requirements. So far, the citizenry as a whole has not risen up and said, "In our constitutional role as the supreme power in the U. S., we collectively decide that capturing carbon dioxide is worth X billion a year to us, and we want it done pronto." Instead, there is a patchwork of voluntary feel-good individual efforts, showcase projects here and there, and large-scale operations such as the one Mississippi Power got permission to do from the state's utility commission, as long as they didn't spend more than $2.88 billion on the whole thing.
So far, it's cost $6.3 billion, and it's still not finished. This means big problems for the utility and its customers, in the form of future rate hikes. Capturing carbon is not a profitable enterprise. The notion of carbon-trading laws would have made it that way, sort of, but for political reasons it never got off the ground in the U. S., and unless we get a world government with enforcement powers, such an idea will probably never succeed on an international level. So whatever carbon capturing is going to be done, will be done not because it is profitable, but for some other reason.
The embarrassment of Mississippi Power's struggling carbon-capture plant is only one example of the larger irony, which is that we don't know what an appropriate amount is to spend on carbon capture, because we don't know exactly, or even approximately, what it will cost if we don't, and who will pay. Probably the poorer among us will pay the most, but nobody can be sure. (There's a lot of very expensive real estate on coasts around the world, and sometimes I wonder if that influences the wealthy class to support anti-global-warming efforts as much as they do.)
The time factor is a problem in all this as well. Nearly all forecasts of global-warming tragedies are long-term things with timelines measured in many decades. That is good in the sense that we have a while to figure out what to do. But in terms of making economic decisions that balance profit against loss—which is what all private firms have to do—such long-run and widely distributed problems are chimerical and can't be captured by any reasonable accounting system. Try to put depreciation on an asset you plan to own from 2050 to 2100 on your income-tax return, and see how far you get.
So the only alternative in many places for large-scale carbon capture to happen is by government fiat. A dictatorial government such as China's could do this tomorrow if it wanted to, but as the recent Paris climate-accord meeting showed, it doesn't want to—not for a long time yet, anyway. In a nominal democracy such as the United States, the political will is strong in some quarters, but the unilateral non-democratic way the present administration has been trying to implement carbon limits has run into difficulties, to say the least.
My sympathies to residents of Mississippi who face the prospect of higher electric bills when, and if, their carbon-capturing power plant goes online. Whatever else the project has done, it has revealed the problems involved in building a hugely expensive engineering project for a payoff that few of those living today may ever see.
