ChatGPT & DALL-E generated image of a 20-meter-high and 2-kilometer-long wall of fans, powered by burning natural gas.

Chevron’s Fig Leaf Part 5: Who Is Behind Carbon Engineering, & What Do Experts Say?

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Carbon Engineering recently garnered $68 million in investment in its air-carbon capture technology from three fossil fuel majors. This is the final article in the 5-part series assessing the technology and the value of the investment.

The first piece summarized the technology and the challenges, and did a bottoms-up assessment to give context for what Carbon Engineering is actually doing. The second piece stepped through Carbon Engineering’s actual solution in detail. The third piece returned to the insurmountable problem of scale and deals with the sheer volume of air that must be moved and the scale of machinery they have designed for the purpose. The fourth article looked at the market for air carbon capture CO2 and assessed why three fossil fuel majors might be interested. The final article addresses the key person behind this technology, David Keith, and the expert opinions of third parties.

As a reminder of what the series has found, the Carbon Engineering solution would use a 2-kilometer long, 20-meter high wall of noisy fans to capture 4 orders of magnitude too little CO2 to make a difference while burning natural gas sufficient for 70,000 households and producing half a ton of CO2 from the gas for every ton it captures from the air. Oh, and the only real use for it is to plant it on played-out oil wells to get more carbon-rich oil from them, leading to exactly zero benefits.

Who came up with this idea?

So we have a technology that burns so much natural gas that they produce and must capture 500 tons of CO2 for every 1,000 they capture from the air. And its natural market is to increase oil extraction. And the alternative to do nothing is free and has lower net carbon emissions. Why would anyone think this is a good idea? It’s a really smart bad solution, but deeply unwise if you actually care about global warming.

Enter Dr. David W. Keith, stage right. He’s the primary engineer behind Carbon Engineering. His name is on the published papers. He’s mentioned in all the articles. He’s chief scientist and on the Board of Directors. He’s a very bright, very credentialed, very connected guy. He took first in Canada’s national physics competition, picked up an MIT prize for experimental physics, and Time Magazine picked him as one of its Heroes of the Environment.

Wait. What? The guy who just sold a net-loss air carbon capture technology using natural gas to people who will use it for enhanced oil recovery is a Hero of the Environment? Why does that sound so familiar? Perhaps it’s because I’ve published a series of pieces recently on the ill-founded, cherry-picked, and biased views of another of Time Magazine’s Heroes of the Environment, Michael Shellenberger, who also doesn’t like renewable energy as a solution, preferring nuclear in its place. What is it with Time Magazine’s HotEs that they get things wrong so badly?

Dr. Keith has game in this regard. He runs The Keith Group, affiliated with Harvard and funded by a bunch of folks including the Gates Foundation (which really ought to look twice at giving money to it) and is devoted to a focus on the science and public policy of solar geoengineering.

What’s solar geoengineering? That’s putting lots of stuff in the atmosphere to avert warming by masking the effects of CO2, which most ethicists and pragmatists agree will do three things. First, it will mean we keep burning fossil fuels and increasing the CO2 concentration of the atmosphere further with all of the detriments to marine life and other things that comes with that. Second, it will be an expensive, annual cost which will have to be done pretty much forever which we will stop doing and lead to another massive warming spell. And finally, it will have tremendous unknown and hard to predict impacts on our ecosystems and the like.

It’s a great thing to research, but a terrible thing to do. Keith is a strong advocate at top policy levels for solar geoengineering. Fossil-fuel companies love geoengineering. Some engineer types love geoengineering. The rest of the world rightly considers it akin to open heart surgery by a 9-year-old without anesthesia and would prefer to simply stop emitting CO2 instead. If we ever resort to geoengineering, we’ve failed.

But there’s more about Dr. Keith. Not long ago he co-authored a study with one of the members of his geoengineering group stating that wind farms would create global warming. Yes, that’s right. One of the major solutions to CO2 emissions from fossil fuels is actually a problem, according to Keith. He and his collaborator’s thinking was deeply shoddy and much mocked when it came out. Once again, that paper was in Joule, the no-impact-factor, brand-new journal that his latest Carbon Engineering paper is in. Perhaps there’s something to be learned from that? The co-author of the wind-farms cause global warming nonsense paper, Lee Miller, was lead author with Keith as co-author in another much-derided attack on wind energy, claiming it had massive limits to the ability to provide power.

Basically, Keith really doesn’t understand or like renewables but loves fossil fuels, and is building a fig leaf for the fossil fuel industry. As I said, very smart but not very wise.

Who else is pointing out that this emperor has no clothes?

Well, returning to Dr. Mark Z. Jacobson, who was quoted in the first article in the series, he doesn’t include air carbon capture in his models for a 100% renewable future. He’s globally acknowledged for his team’s modeling of 100% renewables by 2050 for all US states and the majority of countries globally, providing a clear and sensible policy path. Why doesn’t Jacobson include air carbon capture? He explains it in Why Not Synthetic Direct Air Carbon Capture and Storage (SDACCS) as Part of a 100% Wind-Water-Solar (WWS) and Storage Solution to Global Warming, Air Pollution, and Energy Security .

By removing CO2 from the air, SDACCS does exactly what WWS generators, such as wind turbines and solar panels, do. This is because WWS generators replace fossil generators, preventing CO2 from getting into the air in the first place. The impact on climate of removing one molecule of CO2 from the air is the same as the impact of preventing one molecule from getting into the air in the first place.

The differences between WWS generators and SDACCS equipment, though, are that the WWS generators also (a) eliminate non-CO2 air pollutants from fossil fuel combustion; (b) eliminate the upstream mining, transport, and refining of fossil fuels and the corresponding emissions; (c) largely reduce the pipeline, refinery, gas station, tanker truck, oil tanker, and coal train infrastructure of fossil fuels; (d) largely eliminate oil spills, oil fires, gas leaks, and gas explosions; (e) substantially reduce international conflicts over energy; (f) reduce the large-scale blackout risk due to the distributed nature of many WWS technologies; and so-on.

SDACCS does none of that. Its sole benefit is to remove CO2 from the air. To do that, it costs more than renewable energy.

Triggered in minor part by this series of articles, Dr. Jacobson updated his calculations based on the use of gas generation by Carbon Engineering, and provided an updated perspective.

In the case where the CO2 is captured from the gas plant, 36% of all CO2 captured is effectively re-emitted to the air. The direct cost of CO2 captured from the ambient air per unit grid energy used to produce the CO2 is still 2.2 to 10 times the cost of preventing the emissions in the first place with a wind turbine. The air pollution plus energy social cost of this SCACCS system is $192 to $398/MWh higher than that of wind.

In sum, so long as grid emissions occur, SDACCS will always increase air pollution no matter how low its cost, and SDACCS will always increase CO2e emissions until its direct cost is much lower than that of WWS technologies. Further, it always increases the mining, transport, and processing of fossil fuels compared with using WWS instead.

All of that electricity that’s used to move all that air to find the 411 parts per million could be used for productive purposes and be much more efficient at removing CO2 from the air along with a bunch of other benefits. Seems obvious. Not to David Keith or his fossil fuel sponsors though.

What about carbon capture at fossil fuel source of generation of electricity instead? You know, where all that CO2 is concentrated in the first place? Well, a recent study led by Sgouris Sgouridis at Khalifa University in Abu Dhabi found it wasn’t worthwhile either.

“We show that constructing CCS power plants for electricity generation is generally worse than building renewable energy plants, even when we include the effects of storage systems like batteries and hydrogen,” says Sgouridis. The researchers also discuss significant challenges that CCS promoters would need to address to upscale the technology sufficiently for it to become useful. “These challenges should make the energy policy community very apprehensive about relying on such a solution rather than considering it as a last resort,” Sgouridis says.

That 50% of natural gas CO2 emissions required to fuel the Carbon Engineering air carbon capture? That’s what the Sgouridis paper is talking about; it’s the same thing. Modeling and peer-reviewed research is showing that even the 97.5% CO2 capture from the natural gas combined heat and power solution isn’t worth it.

The first rule of being deep in a hole is to stop digging. Wind and solar electricity being used for productive purposes is much better than using it for air carbon capture. It’s not like the jury is out on this, except for people like David Keith and Chevron.


This concludes the 5-part assessment of Carbon Engineering’s solution, market and investors.

Air carbon capture, especially as Carbon Engineering is doing it, is a fig leaf for the fossil fuel industry. It won’t and can’t scale to the size of the problem. There is no use for the scale of CO2 that would be created in order to be usefully effective. Carbon Engineering’s solution produces half as much CO2 as it captures from the natural gas it uses. It would require the natural gas for 70,000 households’ annual use to get a million tons of CO2, making it much more a new market for natural gas than a solution to global warming. The total CO2 load for the energy required for capture, processing, compression, storage, distribution, and sequestration is almost certain to be greater than the CO2 removed from the atmosphere. It’s easier to get CO2 from biomass, or just bury the biomass, than to do air carbon capture. And it’s much more efficient to just not emit the CO2 in the first place.

No wonder Chevron, Occidental, and BHP love it so much that they were willing to give the company $68 million to play with.

References and Links:

[1] Carbon Engineering: CO2 capture and the synthesis of clean transportation fuels

[2] Capturing Carbon Would Cost Twice The Global Annual GDP

[3] No, Magnesite Isn’t The Magic CO2 Sequestration Solution Either

[4] Air Carbon Capture’s Scale Problem: 1.1 Astrodomes For A Ton Of CO2

[5] Carbon Capture Is Expensive Because Physics

[6] Mark Z. Jacobson – Wikipedia

[7] Climate change ‘magic bullet’ gets boost

[8] Low-Emitting Electricity Production

[9] A Process for Capturing CO2 from the Atmosphere

[10] Joule

[11] Page on

[12] An air-liquid contactor for large-scale capture of CO2 from air

[13] Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences

[14] Parts Sales Fill

[15] How much air, by mass, enters an average CFM56 turbofan engine cruising per minute?

[16] An air-liquid contactor for large-scale capture of CO2 from air

[17] Global Thermostat

[18] Graciela Chichilnisky – Wikipedia

[19] Earth and Environmental Sciences

[20] Europe Stores Electricity in Gas Pipes

[21] The Physical CO2 Market

[22] DigiTool Stream Gateway Error

[23] How much CO2 produced by burning one barrel of oil – since 2011


[25] Harvard John A. Paulson School of Engineering and Applied Sciences

[26] Public Fear Of Nuclear Isn’t Why Nuclear Energy Is Fading

[27] US Could Achieve 3X As Much CO2 Savings With Renewables Instead Of Nuclear For Less Money

[28] US Commentators Point At Germany For Bad Energy Policies, But Live In Glass Houses

[29] Michael Shellenberger – Wikipedia

[30] The Keith Group

[31] Geoengineering Is Not a Solution to Climate Change

[32] Wide-scale US wind power could cause significant warming

[33] Two methods for estimating limits to large-scale wind power generation


[35] The catch with carbon catching

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Michael Barnard

is a climate futurist, strategist and author. He spends his time projecting scenarios for decarbonization 40-80 years into the future. He assists multi-billion dollar investment funds and firms, executives, Boards and startups to pick wisely today. He is founder and Chief Strategist of TFIE Strategy Inc and a member of the Advisory Board of electric aviation startup FLIMAX. He hosts the Redefining Energy - Tech podcast ( , a part of the award-winning Redefining Energy team.

Michael Barnard has 692 posts and counting. See all posts by Michael Barnard