Jan Wurzbacher and Christoph Gebald from the firm Climeworks are coming at the CO² crisis in reverse – they filter CO² from the air. Is their approach too simple a solution?
The first rule of a mechanical engineer is that there’s a solution for everything. The second rule is the simplest solution is usually also the best.
Jan Wurzbacher, 36, from Zurich, Switzerland, has a degree in mechanical engineering. At ETH Zurich, he learned how not to be intimidated by a big problem, how to change your mindset when you’re at an intellectual impasse and why you mustn’t let a complicated question tempt you to give a complicated answer.
In the first week of his degree he got to know Christoph Gebald, a native German who’s now his best friend. At the end of their studies they thought about how a mechanical engineer might solve the most pressing problem of our time – climate change.
“We didn’t want to develop an app or create a platform,” they say. “We just wanted to build a tangible machine that solves the problem. We wanted to apply the knowledge we’d acquired at university.”
Wurzbacher and Gebald are modest in person, but the company they had in mind was anything but ordinary. It was designed to save the world.
It’s now widely known why our planet is in crisis: over the last century, mankind has emitted so much CO² into the air that our climate is on the verge of collapse due to the greenhouse effect. As part of the 2015 Paris Agreement, 197 countries committed to measures to keep warming well below two degrees. Likewise, 77 countries declared at the 2019 UN Climate Action Summit that they wanted to become carbon-neutral by 2050.
Currently, however, only 16 countries worldwide are meeting the Paris Agreement targets and reducing our CO² emissions alone won’t be enough to stop climate change in its tracks.
So, is it an unsolvable problem? Not if you think like a mechanical engineer. “If there’s too much CO² in the air,” says Wurzbacher, “then you have to get it out of the air”.
If there’s too much CO² in the air, then you have to get it out of the air.
Climeworks, the direct air capture company founded by Wurzbacher and Gebald in 2009, has demonstrated for the past three years that this seemingly naive idea is actually feasible. The underlying technical principle is known as a “cyclic adsorption-desorption process”.
In a CO² collector the size of a Smart car, the ambient air is first sucked in by a fan. A filter material – its exact composition is a trade secret – sieves the carbon dioxide from the air until it’s saturated with CO² molecules like a sponge. The absorption phase is now complete. Next, it’s time for phase two – desorption. The entire collector is heated to 100 degrees with renewable energy, the CO² molecules are then released from the filter material and are sucked from the collector by means of a vacuum. Currently this cycle lasts three to four hours and, at present, each collector can filter 50 tonnes of CO² a year – as many as 2,000 trees – and this trend is increasing.
Climeworks shows how this works at 14 locations across Europe. Eighteen collectors in Hinwil have been filtering CO² from the sky above the canton of Zurich since May 2017. And in the south of Iceland, another plant has been making the ambient air CO²-free since October 2017 – fully automatically, controlled by the company headquarters in the Zurich district of Oerlikon. “We deliberately made the design of the machines so simple”, says Wurzbacher, “so that in principle they only need 'on' and 'off' buttons”.
But what to do with the captured CO²? The answer comes from a securely sealed repository in the ground. But because we’d rather not sit on a subterranean gas cloud liable to escape into the atmosphere at the smallest earthquake with unforeseeable consequences, the Climeworks engineers, together with the Icelandic firm CarbFix, are taking advantage of a chemical particularity of CO²: it reacts with minerals. As soon as the carbon dioxide comes into contact with porous basalt rocks at a depth of 700 metres, it forms so-called 'carbonates'. In more understandable terms, it turns into stone.
To turn back the tide, we’d firstly have to reduce our emissions and secondly, within 20 to 30 years, we’d have to establish a whole new industry.
It would be nice if the story ended here. Because from what we’ve just learned, it seems like there might still be a happy ending for our planet. But it’s like any disaster movie, when the problem seems like it’s almost been solved, the monster rears it ugly head again.
Wurzbacher explains: “To turn back the tide, we’d firstly have to reduce our emissions and secondly, within 20 to 30 years, we’d have to establish a whole new industry. This industry would have to perform carbon dioxide removal (CDR) on a large scale. On a very large scale. The new industry may require as much raw material, capital and land as the old industry that generated the emissions with fossil fuels”.
The Climeworks modules can be combined like Lego bricks and expanded without limitation – and they’re fully automated.
What if we could make the cars of the future CO²-guzzlers rather than CO²-belchers?
Climeworks’s current direct air capture systems would in theory be suitable: as modules you can expand them as you wish ("like Lego bricks”) and set them up wherever renewable energy supply and storage sites are found. “Our Research and Development Department is constantly working to make modules more efficient, so they require less material, consume less energy and can filter more CO² in a shorter space of time”, he says.
That’s why some of the 85 employees are already building the next generation for 2023, while another team is busy designing the next but one model for 2025. The Climeworkers – as the company’s employees call themselves – are market leaders in their sector. But for the sake of the good cause, they’re also in close contact with their fiercest competitor, the Canadian company Carbon Engineering, whose investors include Bill Gates. “We see ourselves as friendly competitors”, says Wurzbacher. “We both care about creating a new industry. This requires more than one company – and ultimately there’s enough CO² in the air”.
There’s also enough work to be getting on with: the people of Zurich need to improve their efficiency and reduce their costs to commercially exploit the ingenious idea of 'direct air capture'. At the moment, the filtered CO² is also used as a fertiliser for greenhouses or pumped into soft drinks as carbon dioxide.
But CO² as a waste product might be the raw material of the future. All you have to do is think like a mechanical engineer. What if we could make cars CO²-guzzlers? What if the producer of 18 percent of global CO² emissions were to become climate activists’ greatest ally?
With these thoughts in mind, Climeworks, in collaboration with Audi, is developing synthetic CO²-based fuel. This miracle fuel has properties that are almost too good to be true: it emits virtually no CO² when burnt, can be produced anywhere in the world with locally available raw materials and would save us from fossil fuel dependence. It would make companies like Climeworks the biggest growth industry of the future and thereby make climate protection a huge economic driver.
So, might the disaster movie we’re in actually lead to a happy ending?
