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Climate change and energy

Startups looking to suck CO2 from the air are suddenly luring big bucks

A new Irish firm plans to build a pilot carbon removal plant, relying on technology from the field’s pioneer.
An early prototype of Klaus Lackner's direct air capture concept, in the lab at Arizona State University’s Center for Negative Carbon Emissions.
An early prototype of Klaus Lackner's direct air capture concept, in the lab at Arizona State University’s Center for Negative Carbon Emissions.SPENCER LOWELL

A small band of scientists have been trying to pluck carbon dioxide out of the air for years, despite the deep skepticism of their peers. But the space has suddenly gotten pretty popular.

This week a startup based in Dublin, Ireland, acquired the rights to carbon-capturing technology developed by a pioneer of the field, Arizona State University professor Klaus Lackner. Silicon Kingdom Holdings said it plans to build a pilot project that can capture 100 metric tons of carbon dioxide per day, and eventually develop full-scale plants capable of removing nearly 4 million tons each year.

That follows a series of recent funding deals for other “direct air capture” startups. Calgary-based Carbon Engineering announced in March that it had received an additional $70 million in funding, including investments from major oil and gas companies like BHP, Chevron, and Occidental Petroleum. Late last year, Climeworks of Zurich, Switzerland, said it had secured more than $30 million, pushing its total funding above $50 million.

In addition, Global Thermostat is in the midst of a funding round in which the company is hoping to raise $20 million, the Financial Times reported. And finally, Y Combinator has invested in a California firm called Prometheus (whose founder has made a highly dubious claim that it will profitably deliver competitively priced fuels next year). (See “Y Combinator plans to back carbon removal ventures.”)

A growing number of researchers have concluded that the world will need more and better ways of removing carbon dioxide from the atmosphere to combat the growing dangers of climate change. But some tricky questions have hung over the business of direct air capture. How cheap can the process eventually get? What kinds of businesses can startups build around the ventures? And will there ever be big enough markets for all the carbon dioxide we’d need to capture to meaningfully reduce climate risks?

The improving answers to those questions are why we’re starting to see more money flow into the space. Specifically, scientists are finding that the process could be far less expensive than previously believed, and some business models have emerged that might work—at least in certain markets with sufficient public policy support. (See “Maybe we can afford to suck CO2 out of the sky after all.”)

A number of the startups plan to use the captured greenhouse gas to produce synthetic fuels for cars, planes, and buildings. These would be considered carbon neutral, meaning they would re-emit the captured carbon but wouldn’t require digging up additional fossil fuels.

So some of the new financial interest among legacy energy companies could be a hedge against a future world where it has become increasingly difficult to make a business out of discovery and extraction.

A toehold in the space could also provide those and other investors with ways of securing carbon offset credits, getting in on carbon capture and sequestration incentives like the “45Q” tax credit that the US passed last year, or simply advertising their climate-friendly efforts. (See “The carbon-capture era may finally be starting.”)

Harvard climate scientist David Keith, a cofounder of Carbon Engineering, notes that oil and gas investments are only a small part of the story. He says the increasing interest and funding are driven mainly by a growing recognition of the role that carbon removal technology could, or may have to, play in combating climate change.  

Lackner and colleagues at Arizona State’s Center for Negative Carbon Emissions have developed a relatively simple “mechanical tree” that relies on the wind to bring carbon dioxide in contact with hundreds of polymer strips embedded with resins that bond to those molecules. The machine dips the saturated strips in water, kick-starting a process that releases the gas, which can then be sucked out, purified, and used for other purposes. Those can include fertilizing plants in greenhouses, producing carbonated beverages, extracting additional oil from wells, or, as above, creating synthetic fuels.

Lackner, who will act as an advisor to the new company, contends that relying mainly on wind and water, rather than heat and electricity, will bring down costs. A press release issued on Monday asserted that the process will cost less than $100 per ton when it reaches full commercial scale, in line with the low-end targets of Carbon Engineering and Climeworks.

In an e-mail, Silicon Kingdom chief executive Pól Ó Móráin, who previously worked with Xerox’s venture fund, said that the location and timing of the pilot plant haven’t been determined. He declined to discuss any financial terms of the transaction.

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Illustration by Rose Wong

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