Larger startups like Climeworks and Carbon Engineering are betting that scale will help rein costs in. Both companies use sorbents to draw out the carbon dioxide and use heat to release it from the sorbents so it can be stored elsewhere.
Smaller startups suggest that scale alone won’t be enough, though. “Thermal regeneration is always the expensive step, energy wise,” said Malte Feucht, co-founder and CEO of Phlair, a young direct air capture startup. He may have a point. One study says that capturing a meaningful amount of carbon, around 10 gigatons per year, using Carbon Engineering’s approach would require nearly three-quarters of all the electricity generated in the world today.