World’s first CO2-sucking plant is being used to grow vegetables

How’s this for futuristic: The world’s first carbon-sucking plant is operating and the carbon dioxide it captures is being used to grow fruits and vegetables. Installed on the roof of a waste incinerator near Zurich, Switzerland, the plant literally sucks ambient air—a process called “Direct Air Capture”—before chemically isolating the CO2 and depositing it onto a filter. The gas is then piped underground to a nearby greenhouse, where it helps increase the growth of fruits and vegetables by up to 20%.

Valentin Gutknecht, a business development manager at Climeworks, told Live Science how the plant operates: “The plant consists of several CO2 collectors, which are large boxes with filters inside. We blow air through these boxes for several hours, and after the filter is saturated, we heat the box up to 100 degrees [Celsius, or 212 degrees Fahrenheit] to extract the pure CO2 and regenerate the filters.”

The plant cost $3-4 million to build and the municipal waste incinerator that it sits on top of supplies the heat that it needs at a low cost.

Developed over the last decade by the Swiss firm Climateworks, the plant is the first example of what the founders hope will be many carbon-sucking enterprises. While questions remain over the cost and energy demands of the process, Climateworks hopes to make major technological advances in the coming years and to capture around 1% of global CO2 emissions every year by 2025.

Capturing this 1% would require around 250,000 carbon-sucking plants, a super ambitious goal that would take more than just technological prowess or commercial success, but also political will in the form of a carbon price.

Company founder Christoph Gebald told Carbon Brief that he is very confident that with future plants costs will come down. While the first plant is operating at a cost of about $600 per metric ton of CO2, the long-term target price is $100 per metric ton.

Gebald explained his thinking during a site visit:

In order to achieve this factor-three cost reduction, it’s a combination of facts. It will be procurement, so, purchasing larger volumes, it will be professionalizing our production infrastructure. The plant which we are starting today is more or less handmade in Switzerland, which is maybe not the definition of the cheapest way of producing things. So we are starting to automate production steps: rather than people, drilling or screwing stuff, that’s like, robots, etcetera, can do this. By going step by step, these means that I just mentioned, we can achieve these cost reductions of a factor of three.

In order to again halve the cost, once we reach $200/t, we need R&D to happen. For example, you see a lot of steel behind you, actually stainless steel, which is also not the cheapest [way] to build things. So maybe in the future we can use cheaper materials than steel…I think we cannot reach $100/t simply by scale, or by procurement, but it’s not fundamental research that needs to be done, it’s simply optimization work, which is well known.

The Hinwil-based plant can currently remove 900 metric tons of CO2 from ambient air annually. In the future, captured carbon could be used for purposes other than growing food, such as carbonating sodas, producing carbon-neutral fuels, or simply being sequestered underground.

According to Climateworks, the “plants are modular, scalable and can be located independently of emission sources, allowing security of supply wherever there is atmospheric air.”


While sucking enough carbon from the air may seem like an extreme long shot, it is increasingly being agreed upon that this type of negative emissions technology may be necessary to meet the 2015 Paris Agreement aim of keeping warming “well below” 2C above pre-industrial levels, and at 1.5C if possible. Furthermore, one of the goals of the accord is to improve carbon sink technology in an effort to reach global net-zero emissions sometime in the second half of this century. With national climate pledges lagging far behind what’s needed to meet the demands of these carbon budgets, pulling CO2 from the air could play a crucial role in avoiding the worst impacts of rising emissions.

The planet has already warmed about 1C since the late 19th century. With global climate change mitigation efforts suffering a setback under the Trump administration, more ambitious and innovative ideas may play a bigger role in near-term emissions reductions.

“Paris says we have to go to zero gigatonnes, be CO2 neutral in 20 to 30 years, or by 2050, actually, which requires severe emissions cuts and a combination of all technologies which are available,” said Gebald. “Yes, it took us eight years to get to where we are today, but we started as college graduates, we started without any experience…I’m very confident that we can continue this strong growth, which we had especially in the last two or three years, in order to meet those targets.”