Carbon capture and storage

Carbon dioxide capture and storage (CCS) involves separating CO2 from an emission source gas, transporting it to a storage location, and securing it in long-term isolation from the atmosphere. The three main capture technologies are (1) postcombustion capture, (2) integrated gasification combined cycle, and (3) oxyfuel. All three (first-generation) technologies are associated with higher generation costs with energy penalties of approximately 25%. Current research is focused on cost reduction across the full range of technology. Theoretically, any captured CO₂ can be stored in the geological subsurface, in oceans, or it can be used for mineral carbonation or for industrial uses. Realistically, capture from large point-source emitters such as high-CO₂ natural gas production or power stations (to a lesser extent liquefied natural gas [LNG] plants, mineral processing plants, or cement plants) coupled with geological storage is the most likely large-scale commercial implementation of CCS where projects have four phases: (1) site selection and development, (2) operations, (3) site closure, and (4) postclosure stewardship. Site selection includes assessment that focuses on characterizing injectivity, storage capacity, and containment security. This then dictates the purpose and design of monitoring and the particular choice of the technology dependent on the role it plays in managing the project risk, with emphasis on the reporting to the various stakeholders. While there are now a number of carbon capture and storage projects at a variety of scales operational in the world, including many mature CO₂ enhanced oil recovery operations in North America, more broad deployment of CCS technology is largely dependent on a business case to proceed in the future. The business case is dependent on factors such as the price of carbon, regulatory constraints on the emissions of carbon, and technology advances that reduce the energy penalty and cost of CCS