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Climeworks wants to clean the atmosphere with a fleet of building-sized vacuums

This article is part of Troubleshooting Earth: a multi-part series that explores the bold, innovative, and potentially world-changing efforts to wield technology as a weapon against climate change.

Travel back in time to the Carboniferous period, 300 million years ago, when ancient organisms inhabited lush swamps around the globe. Picture giant ferns, prehistoric trees, pigeon-sized flying insects. Plants are so productive during this period that the atmosphere overflows with oxygen; the primitive vegetation consumes untold tons of carbon dioxide.

When these plants perish, they sink to the bottom of wetlands and decompose beneath layers of sand and clay, carrying their cached CO2 underground. Over the next 300 million years, this pressurized plant matter breaks down into fossil fuels — coal, oil, natural gas — until the Industrial Revolution rolls around and humans begin to make big bucks digging it up and burning it for energy.

Cilmeworks Plan to fight Climate Change | Troubleshooting Earth

Fossil fuels now power the globe. Despite a recent rise in renewable energy, demand for coal, oil, and natural gas hit an all-time high in 2018. That’s a grim sign for future generations. With a rise in the use of fossil fuels comes a rise in CO2 emissions, the leading cause of global warming and climate change. About 37 billion metric tons of CO2 are pumped into the atmosphere globally each year. Without a colossal shift away from our dependence on fossil fuels, and thus a dramatic drop in emissions, experts predict that Earth will continue to barrel towards a climatic catastrophe. To prevent the worst impacts of climate change, the United Nations has warned that we need to cut emissions in half by 2030. Many climate scientists meanwhile insist on zero emissions by 2050.

Eliminating emissions is complicated enough (requiring a sort of choreography of policy, regulation, industry initiative, and pressure from citizens) but what about the hundred-billion metric tons of CO2 that will be emitted into the atmosphere the next few years alone? Without a concerted cleanup effort, this scattered gas may continue to plague the planet.

Climeworks' CO2 Capture Plant in Iceland Climeworks

Undoing the damage

Engineers at Climeworks think they have a solution. Using machines that resemble jet engines, the Swiss startup wants to extract CO2 from thin air. From there, the gas can be siphoned off and sold to carbonated drink companies as fizz for sodas and agriculture companies as fuel for crops. Climeworks already has a deal with Coca-Cola, and it pipes CO2 to a greenhouse that grows tomatoes and cucumbers adjacent to its flagship plant in Hinwil, Switzerland.

The preeminent prospect, however, is in burying the gas underground from whence it came. When injected into basalt rock, CO2 mineralizes within a couple years, locking it away for millennia. The startup aims to sell this service to energy companies and countries with socio-economic incentives to clean up the atmosphere through emissions reversal programs. Climeworks is currently running a pilot program and has plans to expand.

One of the company’s devices has been whirring away in Iceland for the past year and a half. During that times it’s mineralized some 50 tons of CO2, according to the company, which aims to install 50 more collectors at the site outside of Reykjavik, Iceland by the end of the year.

But Climeworks is entering uncharted territory. The firm is one of the first whose aim it is to commercialize the process known as “direct air capture.” That’s because the technology is relatively new, and there isn’t yet a proven market for emissions reversal. Beyond social responsibility, energy companies and, indeed, countries apparently lack significant enough incentives to pay for such a service, since the threat of an uninhabitable planet isn’t incentive enough. And although Climeworks claims its operating costs are decreasing, it has quite a way to go before reaching the $100 per metric ton of CO2 price that experts say is the sweet spot for commercial viability.

Catch and don’t release

Founded in 2009 by Christoph Gebald and Jan Wurzbacher, two Germans who met while studying at ETH Zurich, Climeworks began as something of a pipe dream — a means to make money while tackling “the defining issue of our time.” The pair developed a direct-air-capture prototype after earning their respective master’s degrees and entered the nascent market with the ambition to forge a new industry based on commercializing CO2 capture.

It currently costs them between $500 and $600 to remove a metric ton of CO2 from the atmosphere.

It’s been an uphill battle. A decade on, the company still hasn’t turned a profit. But it has made progress. Climeworks’s CO2 collector has gone through a number of revisions prior to its current prototype. In its current form, the collector uses large fans to draw in ambient air, which is filtered through a specialized material that captures CO2 molecules like insects sticking to fly paper.

Once the filter material is fully saturated, the collector is closed and heated, causing the CO2 molecules to unstick and collect in a container. This highly concentrated CO2 can then be sold as a raw material or injected into the Earth.

For years, skeptics said it couldn’t be done, that the technology simply wouldn’t work. And then, two years ago, when Climeworks proved it could be done, the skeptics changed their tune. It couldn’t be done commercially, they said.

How Cilmeworks Technology | Troubleshooting Earth
How Climeworks’ technology works. Climeworks

Those critics may be right. According to the company’s own calculations, it currently costs them between $500 and $600 to remove a metric ton of CO2 from the atmosphere. Climeworks will need to break the $100 per metric ton mark to become commercially viable, according to Klaus Lackner, director of the Center for Negative Carbon Emissions at Arizona State University (ASU).

“Once it’s below $100 [per metric ton] I think it becomes practically interesting,” Lackner told Digital Trends. “At the small scale, commercial CO2 sells for more than that. For example, if I want to buy a truckload of CO2 every couple of days for my business filling fire extinguishers, I’m going to pay $100 or $200 per ton for that CO2. If you could build devices like that can deliver CO2 at $100, you could enter that market and compete in it.”

“I think there has been a lot of hype about this, and it’s not going to revolutionize anything.”

The Swiss startup is confident that it can scale up its operation and drive down its costs. “Basically, we have a road map — $600, down to $400, down to $300 and $200 a ton,” Wurzbacher told the New York Times Magazine. “This is over the next five years. Down to $200 we know quite well what we’re doing.” Below $200? Well, they’re not yet sure how they’ll achieve that.

Although the game plan for getting below $200 a ton is a bit murky, Lackner (who is developing his own direct air capture device at ASU) thinks it can be done. “It’s very hard to sell CO2 as a commodity for a higher price than someone can buy it,” he said. “Today it’s too expensive to do at full scale. But if you look at photovoltaic [solar cells], it is 100 times cheaper today than it was in the 60s. And wind energy is probably 50 times cheaper than it was at its inception. As we learn by doing, prices come down.

At $500 per ton, the company is already within a factor of five from the $100 threshold, Lackner pointed out. “And it’s still at such a small scale, so it won’t take that much effort to get below $100. This is something that most industries have done. Is that a guarantee that it will happen? No. But it’s very plausible and it’s very likely.”

Cilmeworks Climate Change Troubleshooting Earth
Climeworks’ fully automated CO2 Capture Plant. Climeworks’ modular and scalable vacuum-like CO2 Capture Plant draws in air and chemically binds the CO2 with that air to a filter. Once the filter is saturated with CO2, it’s heated and released into a collection chamber as concentrated CO2 gas. The CO2-free air is then released back into the atmosphere. Climeworks

Lackner and Climeworks are not alone in their optimism. In fact, potential competitors have begun to claim that the $100 price point is in sight. David Keith, a Harvard physicist and founder of Carbon Engineering, a Canadian company that focuses on commercialization of direct air capture, announced last year that his technology could bring costs to around $94 per ton.

Don’t hold your breath

But not everyone is convinced. As with any technology of this complexity, there are a lot of moving parts and competing perspectives on how it might function in the future. Howard Herzog, an engineer at the Massachusetts Institute of Technology who has studies these machines for years, told the New York Times Magazine that costs will likely remain between $600 and $1,000 per metric ton. Behind his reasoning is the fact that the collectors need to filter tons and tons of ambient air to capture a significant enough amount of CO2 — meaning big machines, a lot of energy, and high costs of operation.

“I think there has been a lot of hype about this, and it’s not going to revolutionize anything,” he said. “At best it’s going to be a bit player.”

Lincoln Pratson, a geophysicist at Duke University who has also studied carbon capture and storage methods for years, wasn’t quite as definitive but he does have concerns about the Climeworks model. He told Digital Trends that, while well-meaning, the company’s model could be problematic from a commercial standpoint. It also might not be the most effective approach to removing CO2 emissions from the atmosphere.

“I personally don’t see the advantage [of direct air capture],” Pratson told Digital Trends. “I think the more effective approach would be to try and capture the CO2 at major emissions points. For example, the sort of approach that has been taken to install capture systems at electric power plants that burn coal. If you can prevent a lot of CO2 from going in the atmosphere in the first place, that’s a lot more economic than trying to extract the relatively small fraction of CO2 that is found in ambient air.”

Pratson also wonders whether CO2 will prove valuable (as a commodity or as sequestering service) as the technology advances and more players enter the field. “If we start to capture CO2 on a very large scale, the supply is going to overwhelm the market,” he said. “Right now, there are markets for that CO2, but I’m highly doubtful that those markets will be sufficient at scale and also provide a means for permanently sequestering the CO2.”

Some think resources would be better spent on alternative solutions, including afforestation, enhanced weathering, and bioenergy with carbon capture and storage.

The most promising economic option, in Pratson’s view, entails using captured CO2 for enhanced oil recovery (EOR), in which the CO2 is stored underground and used to loosen up remaining oil in oil reservoirs. “When you burn that recovered oil, it will produce CO2 but there is a net reduction on the order of something like 20 percent in emissions from oil produced by enhanced means,” he said.

Climeworks rejected the idea, stating it will “under no circumstances engage in EOR or any activity that contributes to the release of fossil CO2.”

Climeworks doesn’t exist in a vacuum

Climate change is a complex problem that requires myriad, often complex solutions to address. There are, of course, less high-tech ways to clean up CO2 emissions, some of which date back to the origins of plant life on Earth.

Given the energy and manufacturing needed to develop and operate direct air capture machines, some researchers think resources would be better spent on alternative solutions, including afforestation (planting trees), enhanced weathering (a process that entails distributing crushed silicate rocks to absorb and bind CO2 from the atmosphere), and bioenergy with carbon capture and storage, or BECCS (a process that involves growing CO2 hungry crops, burning those crops for fuels, and burying their emissions underground).

solar and carbon geoengineering examples
Various solar and carbon geoengineering proposals designed to increase solar reflectance or capture and store carbon. Encyclopædia Britannica, Inc

But these alternatives are hardly zero impact. Growing trees and crops requires the use of dwindling resources like fresh water and land area, while weathering and BECCS can burden the environment by infringing on natural ecosystems. It’s estimated that the array of CO2 collectors Climeworks has stationed on top of its roof in Switzerland, has the annual impact of around 36,000 trees.

It’s unlikely that any one of these approaches will solve the emissions issue independently. A more effective approach will be to weave them into a tapestry of solutions, supported by global policy intent on ending climate change.

The Intergovernmental Panel on Climate Change (IPCC) last year reported that we might not be able to limit global warming to 1.5 degrees using clean energy solutions alone. We may need to pull CO2 out of the atmosphere. “If you take all these numbers from the IPCC, you end up with something like eight to 10 billion tons…of CO₂ that need to be removed from the air every year, if we are serious about 1.5 or 2 degrees,” Wurzbacher, the Climeworks co-founder told the New York Times Magazine.

“Can you make the technology so big that you can actually make a major dent in the climate?”

To that end, the Swiss company considers its technology one part of a multipronged effort to pump the brakes on climate change. “We don’t believe Climeworks is the only solution,” the company spokesperson said. “We’re no silver bullet, by any means. Rather, we see ourselves as part of a portfolio of solutions.”

Companies like Climeworks and Carbon Engineering have begun to demonstrate the strength of their role in that portfolio, by proving the success of their CO2 collectors. But the looming question remains: will they be able to scale the technology and have an actual impact on the globe?

Climeworks' Basalt CO2 storage facility in Iceland Climeworks

Build it bigger

Scaling poses no shortage of added complexities, as Glen Peters, a research director at the Cicero Center for International Climate Research in Oslo, described the New York Times Magazine: “You start to get into really big challenges when you get to these big, large scales. If you can do one carbon-capture facility, where Carbon Engineering or Climeworks can build a big plant, great. You need to do that 5,000 times. And to capture a million tons of CO2 with direct air capture, you need a small power plant just to run that facility. So, if you’re going to build one direct-air-capture facility every day for the next 30 years to get to some of these scenarios, then in addition, we have to build a new mini power plant every day as well.”

A harsh realization emerges when profiling a company like Climeworks at a time when the impacts of climate change are beginning to upend communities around the globe. Storms are getting stronger; weather is getting weirder. Earth is at the apparent cusp of a monumental shift instigated by us.

For the past decade, a key question has been whether Climeworks can make money. Indeed, that question pervades the discourse today. In the years to come, it’s success may instead be measured on its environmental impact, not its economic prospect. Companies like Climeworks may be valued not for their ability to turn a profit, but for their potential to help save the planet.

“The big climate change debate is going to change our discussions,” Lackner said. “The real question will become, ‘Can you make the technology so big that you can actually make a major dent in the climate?’ In my view, you can.”

To check out the rest of Troubleshooting Earth, head over to the series homepage.

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