There is a set of technologies, scientists say, without which the world is unlikely to avert climate crisis. These so-called “negative-emissions technologies” have been discussed by climate scientists in academic journals for many years. But now, entrepreneurs at three startups—one each in the US, Canada, and Switzerland—are vying to bring the most promising of those technologies to market. They will potentially offer the world a new set of tools to stave off climate catastrophe—a reverse gear on a car headed for the cliff.
The startups have each been developing a technology called direct air capture. The idea is to build machines that can filter the air and capture only carbon dioxide molecules. If those molecules aren’t released into the atmosphere, the result is negative emissions. So far every startup has showed the technology works. The next hurdle is to scale the technology and lower its cost.
First out of the gate was Climeworks. In 2017, with the help of small grants from the EU, the Swiss startup installed a machine in Iceland that captured carbon dioxide from the air, mixed it with water, and injected it underground. There, thanks to geology, the gas reacted with minerals to become stone. The machine captures about 50 metric tons each year, which is the annual emissions of one household in the US—or about 10 in India.