Elon Musk wants to remove carbon. What is he talking about?

Funded by Tesla's CEO, XPrize Carbon Removal is a $100 million competition to find solutions that can pull carbon dioxide directly from our atmosphere or oceans.

Marta Franco Senior Producer / CNET
Marta is a multimedia journalist and a CNET video producer. After years of writing for the press in Spain, she moved to San Francisco to specialize in video and photography. Based on the East Coast now, she enjoys reading, watching movies, rollerskating, or just having a good meal, an interesting conversation, or a simple stroll under the sun.
Marta Franco

In late January, Elon Musk said on Twitter that he'd donate $100 million toward a prize for best carbon capture technology. The announcement immediately brought attention to technologies that aren't new but remain relatively unknown. 

Carbon capture at the source refers to a process where the carbon dioxide released from burning fossil fuels gets captured and stored. In carbon removal, the CO2 typically comes from the air, in what's called direct air capture, but it can also come from biomass. There are still very few companies working in the field, and the market is very small. Critics say that trying to remove carbon will always be less effective than simply transitioning to renewable energy. Proponents reply that this transition, while essential, won't be enough and that these technologies will be necessary to meet climate change reduction goals. 

Carbon is not the only greenhouse gas emission contributing to global warming, but it's the largest single one. That's why reducing its levels in the atmosphere is so important. Musk is not the only prominent supporter of these technologies. Bill Gates, who has a new book out, How to Avoid a Climate Disaster, has endorsed them as well.