Humanity must remove up to 660 billion tonnes of carbon dioxide (CO₂) from the atmosphere by the end of the century to limit global warming to 1.5°C. That’s according to the most recent report by the Intergovernmental Panel on Climate Change (IPCC), which based its estimate on atmospheric CO₂ concentrations measured in 2020.
Removing this much CO₂ will involve more than simply planting lots of trees. Engineers and scientists are developing direct air capture technologies (DAC) which are supposed to pull vast quantities of CO₂ from the atmosphere while using very little land and water.
A typical DAC unit uses large fans to push air through a liquid or solid material which can bind and remove CO₂, similar to how human lungs extract oxygen. The material is regenerated when heated, leaving concentrated CO₂.
