Carbon Capture:
At this writing carbon capture technology is so expensive that only the petroleum industry has deployed it — where the CO2 captured has been used to increase underground oil recovery1. Mostcarbon capture projects have failed or operated at 50% or less of projected capacity.2
I have not been able to find a reliable and complete analysis of the greenhouse gas impact of carbon capture technology. My own summary analysis, which follows, suggests that the greenhouse gas savings are not worth the huge investments required, and a better use of financial resources would be to replace fossil fuel power plants with nuclear power plants, or not as effective, where appropriate, with solar or wind energy backed up by fossil fuels..
The additional energy required to operate carbon capture is, about 30% of a power plant’s output3. I don’t believe this amount includes the fossil fuels used to construct the facility. To this one must add the energy use for transmission and storage of CO2, and to replace some small amount for leakage of the captured CO2. For argument’s sake, assume the total additional energy needed is 35% of a power plant’s output.
Therefore we need another power plant that operates full time and generates the 35%, which I will assume has also carbon capture. So we need to make that up. So we have 1 +.35 + .123+0.043 +0.015 +0.006. = 1.54 power plants needed (the same result as diving diverting 0.65% of the power of the plant for carbon capture). Assume that only 50% of the CO2 is captured by the power plant. (It becomes much more difficult and expensive to capture more.) The combined power plants emit 77% of the original emissions, that is, the CO2 savings are only 23%.
For the same output of power as a plant without carbon capture the CO2/kWh emissions are reduced from 820 to 631, and methane emissions are increased by 54%. For a combined cycle natural gas power plant, including. upstream CO2 emissions, the reduction is from 420 to 323. Methane emission from natural gas production are increased.
These CO2 emissions are 50 times higher than a new nuclear power plant. They are higher than wind or solar energy backed up by a natural gas combined cycle power plant (without carbon capture) (see my pages on nuclear, wind and solar energy). It appears that financial resources should be invested in nuclear, and also wind and solar power, and not in carbon capture.
- https://ieefa.org/resources/carbon-capture-crux-lessons-learned ↩︎
- https://www.newscientist.com/article/2336018-most-major-carbon-capture-and-storage-projects-havent-met-targets/ ↩︎
- A somewhat lower estimate follows. The direct penalty is said to be 60% of the total penalty. https://www.sciencedirect.com/science/article/abs/pii/S2211467X14000716?via%3Dihub ↩︎
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