Carbon Capture and Storage Overview

The coal industry is betting its future on carbon capture and storage (CCS). They are working to convince policy-makers that they can reduce coal's contribution to global warming pollution and continue to burn coal. The industry is seeking huge subsidies they claim will enable power plants to capture and store carbon dioxide (CO2). CCS refers to technologies that could theoretically allow power plants and other industrial sources to avoid releasing carbon dioxide into the atmosphere and to permanently store it. Currently, storage in geologic formations underground, such as saline aquifers, are the most common proposals. Much is still unknown about this technology, and it is only now being tested at a commercial scale.

Carbon Capture Overview

The separation of carbon dioxide and compression for transport is expected to consume large amounts of energy and water. The 2005 Intergovernmental Panel on Climate Change's ¹ estimated that for a new high-efficiency pulverized coal plant, capturing CO2 would reduce plant efficiency between 24 and 40 percent, or 14 to 25 percent for a gasifi cation-type coal plant. This means that to make up for energy used for capturing CO2, a plant would need to burn 14 to 40 percent more coal. Burning more coal would increase air pollution and solid waste residue from the additional combustion. Mining and transporting more coal would add to those increased environmental impacts.

Carbon Capture: Public Health and Water Resources — Possible Impacts²

• Air and water pollution: Increased nitrogen and ammonia emissions would make water pollution worse. Nitrogen oxide pollution increases health-harming ozone smog.
• Coal ash disposal: Pulverized coal plants would increase coal ash needing disposal by 24 percent; gasifi cation plants would increase ash disposal by 14 percent. Coal ash needs to be carefully stored and prevented from contaminating waterways as happened in the 2008 Tennessee Valley Authority coal ash disaster.
• Demands on water resources: Carbon capture would greatly increase water use at power plants at a time when climate change is already reducing the amount of water available in many places. For a pulverized coal plant, water usage would be more than double the use by conventional plants. For a gasification coal plant, water usage would rise 14 percent Alternative "dry cooling" technologies consume less water, but would use more energy, in turn increasing ash, nitrogen and coal mining-related air and water pollution.

¹ Bert Metz et al, Special Report: Carbon Dioxide Capture and Storage. Intergovernmental Panel on Climate Change. (Cambridge, UK:
Cambridge University Press, 2005)

² Guidelines for Carbon Dioxide Capture, Transport and Storage. (World Resources Institute, 2008) p. 36 table 5, p. 38 table 6

Get the complete document: Factsheet: Carbon Sequestration and Geologic Storage (pdf, 903 kb)

You will need to have the Adobe Acrobat Reader properly installed to view PDF documents. You can get it free from Adobe.