"Carbon capture and sequestration (CCS) is widely seen as a critical strategy for limiting atmospheric emissions of carbon dioxide (CO2)--the principal 'greenhouse gas' linked to global climate change--from power plants and other large industrial sources. This report focuses on the first component of a CCS system, the CO2 capture process. Unlike the other two components of CCS, transportation and geologic storage, the CO2 capture component of CCS is heavily technology-dependent. For CCS to succeed at reducing CO2 emissions from a significant fraction of large sources in the United States, CO2 capture technologies would need to be deployed widely. Widespread commercial deployment will likely depend, in part, on the cost of the technology deployed to capture CO2. This report assesses prospects for improved, lower-cost technologies for each of the three current approaches to CO2 capture: post-combustion capture; pre-combustion capture; and oxy-combustion capture. While all three approaches are capable of high capture efficiencies (typically about 90%), the major drawbacks of current processes are their high cost and the large energy requirements for operation. Another drawback is that at present there are still no full-scale applications of CO2 capture on a coal-fired or gas-fired power plant. However, a number of large-scale demonstration projects at both coal combustion and gasification-based power plants are planned or underway in the United States and elsewhere. Substantial research and development (R&D) activities are also underway in the United States and elsewhere to develop and commercialize lower-cost capture systems with smaller energy penalties."
CRS Report for Congress, R41325