Direct Air Capture of CO2: The Most Dangerous Idea in the World

August 07, 2023

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by Dave Austgen (BioVeritas/Biofuels Digest) It may not be the stupidest idea ever postulated, but it is unequivocally one of the most dangerous. Direct Air Capture or DAC!

To the average person it sounds like a fantastic solution to climate change driven by the increasing stock of CO2 in the atmosphere – let’s just take the CO2 we produce directly out of air by developing new (miracle) technology. This is why oil and gas companies are investing in DAC – it suggests that a breakthrough solution has been found, one that seems very logical and involves the least amount of pain. They know most people will welcome the concept but will not understand its limitations.

It is green-washing at its very worst. Many of the oil and gas companies are using DAC to maintain their societal licenses to operate. That is to say, they are doing so hoping the promise of DAC will allow them to continue to produce high levels of oil and gas over the next 30 years, levels that exceed reasonable reduction targets.

Engineers and scientists, schooled in thermodynamics and techno-economics, recognize DAC for what it is – a ridiculous concept, by far the most expensive way of capturing CO2, virtually an impossible technology to implement at a scale that would make even the smallest dent in the stock of CO2 in the atmosphere much less capture all the new CO2 entering the atmosphere. From an economic perspective, it is the most inefficient investment in CO2 abatement.

But the oil and gas companies do not need to invest significant sums to keep their licenses to operate. They just need to sell the Promise they can remove CO2 directly from the air.

They are saying to us, metaphorically, “Don’t Look Up.”

We are far better off, from a societal perspective, planting trees than investing in DAC. And to reduce emissions in the short term, we should continue to deploy solar, which has become the cheapest source of power in many parts of the world, and continue to shut down coal power plants, which are the biggest emitters of CO2. This is far and away the cheapest way of reducing CO2 emissions.

Many oil companies started investing in renewable energy in the 2000’s and 2010’s. Now many are moving away from those investments and back to their core businesses (just do a google search on direct air capture – O&G company after company are investing in projects).

Those of us in the engineering and science communities have a responsibility to speak out against DAC. The concept inarguably represents an existential threat to the world by allowing oil and gas companies to continue producing at current levels rather than reducing production to levels needed to prevent a climate catastrophe. READ MORE

Rowing in a Lake of Peanut Butter: Reader reaction and hard data on Direct Air Capture (Biofuels Digest)

At least 13 projects vie for $1.2B in carbon removal (E&E News Climatewire)

The U.S. Government Will Pay to Remove Carbon From Atmosphere: The key climate technology lands a big customer. (HeatMap)

JPMorgan ‘Trying to Lead’ In Carbon Removal, Bank Says: The bank is jumping into the carbon removal market, and Brian DiMarino, its head of operational sustainability, is the driving force. (Bloomberg)

Excerpts from Biofuels Digest: Is Direct Air Capture of CO2 really the most dangerous technology in the world? Following a column penned by BioVeritas CEO Dave Austgen that led The Digest yesterday, a friend wrote:

The headline made me want to open up [The Daily Digest], but there are no significant facts or reasoning stated in [the] article as to why DAC is bad. This may be a great technology that is still trying to be proven. We might be skeptical, but I applaud the scientific community for trying to give it a go. I agree that the O&G industry may be using this as a way of ‘greenwashing’, but you are leading people to completely discount the ideas and concepts.

I believe the column was intended more as a wake-up call for those scientists and engineers who have done the numbers on DAC, see the problem, but have not spoken up. However, perhaps there’s a need to discuss the technical data relating to DAC in more detail. Let me summarize:

The Fortunatelys and Unfortunatelys

Fortunately, plants and trees do Direct Air Capture of CO2 for free, and it’s a great thing.

Unfortunately, the current industrial DAC approach is a planet-scale HVAC system, you’d process an estimated 23 quintillion liters of gas per year to capture the 2.26 ppm carbon we add into the atmosphere each year. That’s 30,000 times the size of the US methane-processing industry,

Fortunately, you could build it.

Unfortunately, based on the current cost of gas processing cost — using methane processing as a good proxy – it would cost an estimated $2.4 quadrillion to build. That’s the global GDP through (roughly) 2050, to price it as a Net Zero strategy.

Fortunately, there’s new tech, from companies like Oxy. And they project a cost of around $1100 per ton for construction at million-ton scale.

Unfortunately, that’s still $42 trillion to Reach Net Zero. Removal of enough carbon to return to more benign 1970 levels would be another $80 trillion or so if the goal was to accomplish this by 2075 or so.

Fortunately, there’s talk of a target of $150 per ton in 3-10 years — and the DOE has a 10-year target of $100 per ton.

Unfortunately, using the best tech today, the energy cost alone (using, say, cheap, climate-wind power) costs about $72 per ton; even if amortizing the construction costs over 30 years, the $100 per ton target is unachievable even before considering operation costs such as labor, taxes, maintenance, power transmission, carbon storage and transport.

Fortunately, some companies speak in terms of even more massive projects with more economies of scale.

Unfortunately, you need about 300MW of power to support a million-ton facility, and that’s perilously close to the maximum power delivered to individual location such as an oil refinery — much bigger than that, even more invention required.

Fortunately, there are big grants and tax credits available for these technologies, as much as $180 per ton.

Unfortunately, the cost of tax credits to reach Net Zero would be $6.8 trillion per year, more than the US government takes in.

Fortunately, technology might solve the cost problem some day.

Unfortunately, it takes 38,000 projects to reach Net Zero with this pathway, or roughly 1500 per year. They take about 30 months from ground breaking to full operation, so people would be building around 3,800 of these at the same time.

The Bottom Line

Let’s focus on this, the macroeconomic problem. Why would we ever process a million liters of gas to extract 421 liters of carbon dioxide? By definition, 99.96 percent of the work is processing benign air. It’s rowing in a lake of peanut butter — so much effort to get to the other side.

At some point, a discussion of climate change technology becomes, like chess, not just a discussion of the value of the pieces but the order of the moves. Why this move now – why expose a Queen so early in the game?

Alternatives abound. Planting more trees, point source carbon capture, direct sea capture, biofuels, EVs, hydrogen, recycle. Those now, DAC later. Right now, there’s too much of the “high cost, low impact” problem in DAC.

Yes, costs can go down — but its tough when power, steel, labor and land are the components of scale. This isn’’t solar panels, which sell for $30,000 per ton even in these times, and where manufacturing cost is key. Yes, impact can increase — but power supply, construction, permitting, labor, project management, markets for carbon sequestration or use, all of these are bottlenecks. Maybe some of them don’t matter, but look at the number of them, as Sam Spade said towards the end of The Maltese Falcon as he explained to Bridget O’Shaunessey why she was talking the fall.

I had the good fortune to have a number of interviews with the father of fracking, George Mitchell, late in his career. The path to fracking and horizontal drilling took time, the first iteration did not work as planned. Neither did the twelfth, the fifteenth. Good ideas take time and good ideas in the world of industrial scale take a lot of time.

Maybe some time down the line a better approach will emerge, or the current ideas will have matured.

Until then, let us also take time to look at the numbers, the hard data, to gaze deeply into the abyss even as the abyss gazes into us, as Nietzsche put it, and gasp at the costs and the risk. READ MORE