How it works: This device relies on panels made of a thin plastic membrane that traps carbon dioxide, pictured here atop a supporting structure.
The panels can be cleaned by placing them in a humid environment. The carbon can then be buried deep underground.
Each machine can capture the same amount of carbon as 1,000 trees. About 1 million of them would need to be deployed to keep carbon in the atmosphere at an acceptable level, according to Columbia Professor Klaus Lackner, who designed the system.
The main problem: The system uses electricity, so it would need to be supplied from renewable sources to produce substantial results. And some have questioned whether carbon stored underground will actually stay there for the long-term or eventually seep back up to the earth's surface.
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