Continuing our series of Nat Bullard's climate charts, here's one about carbon capture:
This surprised me. I didn't realize CCS had increased over the past few years, let alone by a lot.
(But the numbers are still pretty low in absolute terms. Operational capacity in 2023 was 50 million tons compared to global CO2 output of about 40 billion tons. That's a tenth of a percent.)
Unlike solar and wind, however, the cost of CCS hasn't been decreasing. That makes its future growth a lot less rosy than it is for renewable energy.
Carbon capture is hard to do, unless you happen to be a tree.
Or oceanic phytoplankton.
"the cost of CCS hasn't been decreasing"
I wonder how much money has been invested in carbon capture research vs solar/wind. Also, solar/wind had a huge head start, with electricity generation from wind I thnk first happening in the late 1800's and photovoltaic cells developed in the 1950s. CC research didn't get going until the 1990s.
The reason for the stubbornly high cost is not lack of diligence. Filtering tiny amounts of CO2 out of the air requires handling large volumes of air and a complicated way to "catch" the CO2. One such process (based on the process of manufacturing cement) goes like this.
1. take lime and heat it to very high temperatures (which, ironically, is most easily done with combustible fuels). Then it loses CO2 and become Calcium oxide (from Calcium carbonate.)
2. The CO2 can be collected and stashed away (most cement manufacturers save money by not doing that).
3. expose the oxide to air (at normal temperature). It will suck up CO2 from the air and turn back into lime (carbonate).
4. Use that lime in the first step.
And round and round.
The energy for the heating and for all the mechanical work necessary must be produced by solar or wind, other wise the whole thing is net negative.
There is a special case: If you take exhaust from processes of combustion (steel manufacture fore example) the concentration of CO2 in your gas is much higher (like a thousand times higher) than in environmental air. This should be considerably cheaper to filter with simpler methods than the one I described. I think this is the only economically justifiable way of doing it (in those special cases like steel or cement manufacture where no alternative processes exist).
CCS is not about scrubbing existing CO2 from Earth's atmosphere. That's carbon sequestration. Artificial carbon sequestration at meaningful scale is... well, I won't go so far as to say it's a pipe dream, but it's a wildly ambitious concept that is a long long way from any practical implementation.
CCS (carbon capture and storage) is what you described in the last paragraph. It's about finding places where we're dumping a lot of concentrated CO2 into the atmosphere, and trapping that CO2 before it's released.
Your statement vis a vis the relative change in costs of renewables vs carbon capture suggests to me that at least part of the deflator for renewables has nothing to do with technological progress.
Volume production creates its own cost reduction curve apart from technological improvements. I'm not sure carbon capture will have the same mass production benefit since, at least so far, the projects have been large scale and one-off designs.
You mean the way volume increases when some company or polity engages in dumping as a deliberate policy?
So far carbon capture has been used by the oil inductry as an excuse not to reduce production not as an valuble carbon reduction method.
Things like solar power looked very expensive for a long time. Then some advances were made and economies of scale came into play. Carbon capture is worth spending money on, but it should not bar spending money on other things. So far it has not impeded other ways of reducing carbon dioxide in the air.
Technology isn't magic. The reason CCS is expensive (and frankly, a stupid area to pour research money into) is because of thermodynamics. CO2 is at the very bottom of the hill; to capture it and turn it into something that isn't going to go right back into the atmosphere and you have to dump collosal amounts of energy into the process and run it *back* uphill, energetically speaking.
But if you have colossal amounts of energy to dump into the process, you might as well just use that energy in the first place to do whatever things it is that you wanted to accomplish by using fossil fuels (generate electricity, move cars around, melt steel, etc.) and not engage in a goofy rupe goldberg process of burning fossil fuels to make energy and then using other energy to un-burn the fossil fuels.
So, CCS is really only something that might be of use for the rare edge cases where carbon is emitted from some process *not* to generate energy, and/or things that are very difficult to electrify (like airplanes). It is not, and cannot be, a solution to fossil fuel carbon emissions at any significant scale.
"So far it has not impeded other ways of reducing carbon dioxide in the air."
Unfortunately, it absolutely has. Utilities around the country are building out gigawatts of new gas-fired generation with the theory/hope/excuse that in ten years CCS (or magically cheap zero carbon hydrogen) will be available to purge our carbon sins and let us continue operating those new gas-burners forever so in the meantime it's party-time.
It's not about un-burning the carbon dioxide (which indeed would be absurd). The goal is to capture the CO2 as it's being emitted and store it, such as by converting it into carbonate salts or injecting it deep into the Earth's crust.
Whether this can be done efficiently enough to be worthwhile is not clear, but it's not an obvious violation of thermodynamics.
Sure, CCS is increasing, but scale. CO2 emissions increased 400 megatons between 2022 and 2023. Can't even illustrate that difference in scale on that chart.