The world's largest fans designed to suck carbon from the air are up and running in Iceland

Climeworks

• Climeworks' direct-air-capture plant can remove up to 36,000 metric tons of carbon from the air a year. 
• Carbon removal is becoming a key climate technology because the world isn't cutting emissions fast enough.
• The tech is still in its early stages and expensive, ranging from $600 to $1,000 per ton of carbon.

The startup Climeworks this week switched on the largest direct-air-capture plant...