Swiss company opened the first commercial carbon-capture plant in the world

The world's first commercial plant for capturing carbon dioxide directly from the air opened on May 31th, refueling a debate about whether the technology can truly play a significant role in removing greenhouse gases already in the atmosphere. The Climeworks AG facility near Zurich becomes the first ever to capture CO2 at industrial scale from air and sell it directly to a buyer.

Developers say the plant will capture about 900 tons of CO2 annually — or the approximate level released from 200 cars — and pipe the gas to help grow vegetables.

While the amount of CO2 is a small fraction of what firms and climate advocates hope to trap at large fossil fuel plants, Climeworks says its venture is a first step in their goal to capture 1 percent of the world's global CO2 emissions with similar technology. To do so, there would need to be about 250,000 similar plants, the company says.

"Highly scalable negative emission technologies are crucial if we are to stay below the 2-degree target [for global temperature rise] of the international community," said Christoph Gebald, co-founder and managing director of Climeworks.

The plant sits on top of a waste heat recovery facility that powers the process. Fans push air through a filter system that collects CO2. When the filter is saturated, CO2 is separated at temperatures above 100 degrees Celsius.

The gas is then sent through an underground pipeline to a greenhouse operated by Gebrüder Meier Primanatura AG to help grow vegetables, like tomatoes and cucumbers.

Gebald and Climeworks co-founder Jan Wurzbacher said the CO2 could have a variety of other uses, such as carbonating beverages. The company was founded by engineers Christoph Gebald and Jan Wurzbacher, who first came up with the idea for the DAC plant in 2008 after visiting the greenhouses of agricultural enterprise Gebrüder Meier Primanatura AG in Hinwil, Switzerland. They were both students at the Swiss Federal Institute of Technology in Zurich (ETH) at the time.

The Hinwil plant will operate as a three-year demonstration project in co-operation with the partners Gebrüder Meier and KEZO, and with a contribution towards non-amortisable costs by the Swiss Federal Office of Energy (SFOE). In the next year, the company said it plans to launch additional commercial ventures, including some that would bury gas underground to achieve negative emissions.

"With the energy and economic data from the plant, we can make reliable calculations for other, larger projects," said Wurzbacher.

There are many critics of air capture technology who say it would be much cheaper to perfect carbon capture directly at fossil fuel plants and keep CO2 out of the air in the first place.

Among the skeptics are Massachusetts Institute of Technology senior research engineer Howard Herzog, who called it a "sideshow" during a Washington event earlier this year.

He estimated that total system costs for air capture could be as much as $1,000 per ton of CO2, or about 10 times the cost of carbon removal at a fossil fuel plant.

"At that price, it is ridiculous to think about right now. We have so many other ways to do it that are so much cheaper," Herzog said. He did not comment specifically on Climeworks but noted that the cost for air capture is high partly because CO2 is diffuse in the air, while it is more concentrated in the stream from a fossil fuel plant.