To avoid catastrophic global warming, the Intergovernmental Panel on Climate Change estimates, humans will need to remove 100 billion tons to 1 trillion tons of carbon dioxide from Earth’s atmosphere by the year 2100. To reach the upper end of the range, we’d have to suck up all the carbon that’s already been emitted this century—and then some. Today global carbon removal stands at about 40 million tons, mostly straight from smokestacks. For purpose-built projects that grab CO₂ from the open air, the number is more like 8,000 tons, at a cost of $600 apiece or more. At that rate there isn’t enough money in the world to get to 1 trillion tons.
If there’s a sliver of good news here, it’s that the U.S. government has finally decided to try changing the math. Late last year the U.S. Department of Energy announced what it calls a “carbon negative shot” as part of its Energy Earthshots Initiative: a significant investment in technologies meant to take, eventually, a billion tons of carbon from the air each year for the relatively affordable price of $100 a ton. The bipartisan infrastructure law that passed in mid-November has funded the effort with about $3.5 billion. That’s not exactly climate-curing money, but it represents the government’s first serious investment in such remediation efforts.