What Is Carbon Storage?

What is carbon sequestration?

(Carbon Capture and Storage)

Carbon capture and storage (CCS) is the separation and capture of carbon dioxide (CO2) from the atmospheric emissions of industrial processes and the transport and safe, permanent storage of the CO2 in deep underground geologic formations.

By preventing CO2 from large-scale industrial facilities from entering the atmosphere, CCS is a powerful tool for addressing potential climate change. Geologic storage is defined as the placement of CO2 into a subsurface formation so that it will remain safely and permanently stored. DOE is investigating five types of underground formations for geologic carbon storage, each with unique challenges and opportunities:

  1. saline formations
  2. oil and gas reservoirs
  3. unmineable coal areas
  4. organic-rich shales
  5. basalt formations

The CO2 for geologic storage comes from industrial facilities that emit large amounts of CO2, particularly those that burn coal, oil, or natural gas. These facilities include power plants, petroleum refineries, oil and gas production facilities, iron and steel mills, cement plants, and various chemical plants. In CCS, CO2 is not removed from the atmosphere. Rather, CO2 that would otherwise have been emitted into the atmosphere is captured and disposed of underground. CCS enables industry to continue with less disruption, while minimizing industry’s impact on climate change. Many studies show that CCS could make a significant contribution to reducing CO2emissions. The greatest emissions reductions are achieved when all options for reducing CO2 emissions are utilized, including energy efficiency, fuel switching, renewable energy sources and CCS.

The CCS process includes monitoring, verification, and accounting (MVA) and risk assessment at the storage site. DOE’s MVA efforts focus on the development and deployment of technologies that can provide an accurate accounting of stored CO2 and a high level of confidence that the CO2 will remain permanently stored. Effective application of these MVA technologies will ensure the safety of storage projects, and provide the basis for establishing carbon credit trading markets for stored CO2 should these markets develop. Risk assessment research focuses on identifying and quantifying potential risks to humans and the environment associated with carbon storage, and helping to identify appropriate measures to ensure that these risks remain low.

Carbon Storage Diagram
Carbon Storage Diagram
(click image to enlarge)

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