As coal is mostly carbon, burning it produces a lot of carbon dioxide. The IEA said in 2022 that ‘achieving a swift reduction in global coal emissions is the central challenge for reaching international climate targets’.
Carbon sequestration technology, to remove significant quantities of carbon dioxide from the air, has yet to be tested on a large scale and may not be safe or successful. Sequestered CO2 may eventually leak up through the ground, may lead to unexpected geological instability or may cause contamination of aquifers used for drinking water supplies. Carbon capture and storage is applied at large point emitters of carbon dioxide with the objective of preventing it from entering the atmosphere.
As approximately 37% of the world energy consumption in 2022 was from coal, reaching the carbon dioxide reduction targets of the Paris Agreement will require modifications to how coal is used.