Removing Carbon from the Air

KLAUS LACKNER — DIRECTOR, CENTER FOR NEGATIVE CARBON EMISSIONS

Klaus lackner first floated the idea of removing carbon directly from the air as a way of putting the brakes on climate change in 1999, and he has been devoted to figuring out how ever since.

His single vision can seem like tilting at windmills. The prospect of keeping up with the 33 billion tons of carbon the world releases into the atmosphere each year, let alone removing enough of it to return to pre-industrial levels, is daunting. But the vastness and urgency of the problem argues for pursuing every available means. Lackner’s leadership has helped focus some of the world’s best minds on carbon capture.

For years, Lackner, a professor at the School of Sustainable Engineering at Arizona State University, has worked to develop a mechanical tree that removes carbon dioxide a thousand times more efficiently than natural trees and requires no energy to operate. It relies on wind to blow air past resin-encrusted discs, which absorb the greenhouse gas (to be eventually stored permanently underground or reused in industrial processes). A Dublin-based tech company, Carbon Collect, got $2.5 million from the Department of Energy this summer to build three “carbon farms” of Lackner’s trees capable of capturing 1,000 tons of the substance each day—about 1,844 American households’ worth of emissions.

Carbon capture is now moving into the mainstream. Elon Musk, Microsoft and Occidental Petroleum have made large financial commitments in the last year to technologies for taking carbon directly from the atmosphere. Currently 19 direct-air capture plants are operating around the world, the largest of which came online in September in Iceland. The federal government offers tax credits and the infrastructure bill passed in November includes more than $10 billion for carbon-capture projects, including $3.5 billion to build four regional direct air capture hubs.

It’s too early to know if carbon capture will ever amount to more than a drop in the climate bucket. But if someone eventually figures out how to make it work at scale, we’ll all owe a debt to Lackner.