What is carbon capture and storage?

Carbon capture and storage is a process that prevents carbon dioxide from entering the atmosphere when it is emitted from sources such as coal-fired power plants. A related term is carbon dioxide removal, which refers to methods for taking carbon dioxide back out of the atmosphere, either by using technologies or enhancing natural processes - by expanding forests and wetlands, for example.

Both carbon capture and storage and carbon dioxide removal often involve a step that locks away the carbon dioxide for a long time, making sure it can't re-enter the atmosphere. This is called carbon sequestration. The carbon dioxide can be 'stored' by being used in products like building materials, or it can be pumped underground where it reacts with certain kinds of rocks, locking it inside.

Alyssa Gilbert, Director of Policy and Translation at the Grantham Institute, Imperial College London, says, 'Many countries are working to reduce their carbon emissions, and these reductions are the central pillar to tackling climate change. But there are some areas where reducing emissions is particularly difficult - in some types of heavy industry, for example. This means we will need to remove some carbon dioxide from the atmosphere to limit climate change. However, many carbon removal technologies and methods are not well developed yet. The slower we reduce our emissions, the more we will need to rely on these methods that may not be available to pick up the slack.'