Your questions answered: Carbon Capture & Storage

Carbon capture and storage (CCS) is increasingly seen as a prerequisite to the continued use of fossil fuels. If you can’t prevent carbon dioxide (CO2) reaching the atmosphere, the argument goes, then you can’t burn the fuel. But CCS has still never been demonstrated at full scale and its costs are uncertain.

We invited readers to pose their questions on CCS to experts in industry and academia.

This selection of questions was answered by:

Tim Bertels (TB), manager of the CCS portfolio at Shell;
and Niall McDowell (NM) and Paul Fennell (PF) of the Energy Futures Laboratory at Imperial College London.

NM/PF: CCS plants require energy for flue gas fans, amine recirculation pumps, amine regeneration, CO2 compression, CO2 dehydration, auxiliaries, etc. The amount of energy needed is broadly equivalent to the tonnes of CO2 to be captured and compressed. The parasitic load, as loss in thermal efficiency, of specific power plants is dependent on the efficiency and CO2 intensity of the unabated plant; for example, a coal CCS plant needs to capture and store more
than twice the amount of CO2 per megawatt produced than a gas CCS plant.