Direct Air Capture: Billionaires dream of vacuuming carbon out of the atmosphere

By: Fredrik Lundberg

Direct air capture of CO2 is getting a lot of media traction, and a lot of finance from US billionaires. But the very few machines do not suck up much CO2, so Carbon Engineering uses Photoshop to increase their numbers.

Direct Air Capture (DAC) is a simple idea. It means sucking up CO₂ from ambient air with big fans, capturing it in a liquid and disposing of it.

This is what a tree, or other photosynthesising organisms do. Can a machine do it better and cheaper? Can it do it on a relevant scale to stop and reverse climate change?

One of the few companies behind the DAC media blitz is Canadian Carbon Engineering, which claims that it is engineering a DAC plant that will capture one million tons/year, and will start construction in 2023. If so, it will be by far the largest such plant in the world.

If this really happens, and the plant operates at capacity, it is important to put one million tons in perspective. Global CO₂ emissions were 31,500 million tons in 2020, so it will take a lot of DAC to make a dent. Wind and solar produced 2,154 TWh of electricity globally in 2019, which with the present world energy mix means that they mitigated CO₂ emissions by just over 1,000 million tons that year, with much more to come.

The one million tons that Carbon Engineering is aiming for will not exactly be one million tons of mitigation, as the CO₂ is to be used for enhanced oil recovery in Texas . The more CO₂ that goes into the well, the more oil will be produced.

Occidental is one of the financiers. Carbon Engineering is also backed by Bill Gates, Chevron, and BHP and oil sand financier N. Murray Edwards. It has also received funding from the Canadian government.

Carbon Engineering says that the energy input for capturing one ton of CO₂ is either 10 GJ of natural gas or 1500 kWh .

The latter figure is more relevant, because a lot of electricity is needed to run the giant fans. If this electricity is generated using coal power, the whole system will emit more CO₂ than it will capture.

If the electricity is renewable the effect will still be the same. New renewable power will then drive DAC fans instead of replacing fossil power.

This is why many of the billionaire backers, such as Bill Gates, want new kinds of nuclear power – to power the DAC plants.

Yet another billionaire, Peter Thiel, the founder of PayPal, a Trump advisor and big-time Republican Partydonor, is behind Climeworks in Switzerland, the one company in the world that actually sells DAC systems (though not many). Thiel is a climate skeptic, is opposed to women’s right to vote, and has injected himself with young people’s blood in order to postpone or inhibit his death.

Bill Gates is behind Climeworks, too. His Breakthrough Institute, which supports DAC, nuclear and this and that, is also financed by the Putin-ish oligarch and major shareholder in Facebook and Twitter, Yuri Milner, renowned from the Panama papers .

The largest plant that uses Climeworks tech and the largest DAC plant in the world is on Iceland, next to a geothermal plant. It captures 4,000 tons (0.004 million tons) of CO₂ per year .

It uses even more energy than Carbon Engineering: 2000 kWh of heat and 650 kWh of electricity per ton of CO₂, and those are “figures expected for scaled-up machines”.

Climeworks offers subscriptions for negative emissions . For €49/month you can save 0.6 ton of CO₂ per year. That is €980/ton, which may be a realistic estimate of the cost of DAC, but is more than 20 times the CO₂ price in the EU emission trading system.

They use alkaline rock (basalt) to absorb the CO₂. This rock exists because Iceland is volcanic, and volcanoes emit very alkaline rock. If left alone this rock will slowly absorb CO₂ from the air and become less alkaline.

“We turn CO₂ into stone”, is the slogan of the Icelandic company Carbfix that uses the Climeworks technology.

Unless you have fresh volcanic rock, the storage part will be even more difficult and expensive. The plant in Iceland offers other unusual advantages. It gets free heat from the nearby geothermal plant, and electricity on Iceland is abundant, coming either from geothermal or hydro power. Water is also abundant, which is not the case everywhere. The plant also gets money from the EU  on top of that from US billionaires.

On a smaller scale, Climeworks has released CO₂ from one of its plants into a greenhouse, where it enhances the growth of produce. But the final fate of that carbon is not known.

Carbon Engineering uses some CO₂ combined with hydrogen to produce synthetic fuel, on a scale at which cost per litre is no object.

They now have what appears to be their first customer. They sell negative emissions to Shopify, an e-commerce company led by billionaire Tobias Lütke – 10,000 tons from a plant they hope to build one day.

A third DAC manufacturer is Global Thermostat, based in New York and supported by Exxon. They claim they “intend to build a one gigaton plant”, but even a much smaller 20,000 ton/year plant for a supposed contract with Coca Cola is getting nowhere .

Still more billionaires believe in Direct Air Capture. As might be expected, Elon Musk is one. He has instigated a $100 million prize  for what he with characteristic modesty calls “Gigaton-Scale Carbon Removal”, with a photo of himself against the background of the Earth from space.

But the world’s richest man is trying to do things on the cheap. A $100 million prize will not achieve gigaton removal.

Clean energy investment totalled $500 billion in 2020, according to Bloomberg New Energy Finance.

But could DAC benefit from economy of scale, learning curve, etc?

A little, yes, but not by very much.

The major components are fans, tubes, pumps and absorption chemicals. They have all been produced on a very large scale for a very long time. There is no way to achieve a radical cost reduction, such as happened with electronics and non-crystalline solar cells.

Reinventing the tree should also be compared with actual trees. One study  has estimated a potential of 205 gigatons of carbon capture from reforestation and afforestation. As with all such studies, the result is contested, but not the order of magnitude, and there are additional ways of enhancing natural carbon sinks.

Forests deliver a lot more than just carbon removal: biodiversity, clean water and clean air for starters.

A few hundred thousand giant vacuum cleaners, using huge amounts of dangerous chemicals, could do the same job but for a much higher price.

Another thing the billionaires have in common is that they want us to go to Mars, presumably because their egos are too large for just one planet.

But that planet is the one we have.

Nuclear-powered DAC has no chance of saving the planet. All the money in the world can’t buy that. But a few billions spent by the billionaires can influence the discourse in ways that are both subtle and less subtle.

The so-called startup Climate Engineering (set up in 2009) has little to show off in the real world. So they produce fictional images of a lot of non-existent plants. They managed to get such an image published together with a promotional news article in Science Magazine . It was also published by Bloomberg’s AP News, the Houston Chronicle and several hundred other publications. The Guardian at least mentioned in its caption that it was an “artist’s impression”. Most did not.

A striking image that costs nothing is very tempting for a magazine or newspaper – even when it is fake.


Fredrik Lundberg











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