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Carbon Sequestration Fact Sheet
Maintaining Economic Strength in a Carbon Constrained World
The Need for a Sequestration Research Program:
Currently, over half of the electricity presently generated in the U.S. is produced in coal-fired power plants. The U.S. power generation industry needs to maintain a diversified fuel mix to ensure adequate energy supplies at a reasonable price. The future use of coal is threatened by numerous environmental issues, especially global climate change.
Ultimately, to maintain stable concentrations of greenhouse gases in the atmosphere while permitting world-wide economic growth, it will be necessary to sequester carbon from fossil fuels. Renewable energy sources alone, can not meet the challenge. Switching from coal-based power generation to natural gas will not be enough to stabilize atmospheric concentrations of greenhouse gases. The Kyoto protocol is just the beginning of efforts to curb the worlds carbon dioxide emissions to address global climate change issues. Inevitably, we will need safe and economic ways to capture and sequester carbon.
Capture and storage of CO2 has the potential to enable the coal-fired utility market to maintain its presence and continue to provide fuel diversity for power generation, and retain the affordable electrical energy needed to fuel the U.S. economy. Many U.S. energy producers (e.g, the National Mining Association) are now recognizing the major role carbon sequestration can play in keeping fossil fuels, mainly coal, in the energy mix for the foreseeable future.
The Challenge
Carbon dioxide capture technologies can be used to concentrate CO2 from combustion of fossil fuels and natural gas processing units. However, the costs associated with capturing CO2 from large utility boilers, transporting it to the coast, and sequestering it in the deep ocean have been estimated to be very high -- in the $50 to 75 per ton range. This could nearly double the retail cost of electricity. Additionally, over 30% of the power now generated would be parasitically consumed by the capture and disposal process. Moreover, the environmental and safety aspects of disposal of enormous quantities of CO2 have not been adequately addressed. For plants not near the coast, the options are very limited.
We need to develop economic technology to capture CO2 during power generation, and safe ways to permanently sequester carbon at reasonable cost less than $15 per ton of CO2 . We need options that are applicable to power plants across the whole U.S. We need high efficiency power generation technology such as that being developed as part of "Vision-21". Only then will we be able to stabilize atmospheric concentrations of greenhouse gasses at reasonable levels and still maintain economic growth.
Promising Opportunities for Sequestration
Potential storage sites include geologic structures, such as oil and gas reservoirs, unmineable coal seams, deep saline aquifers, and the oceans. The Federal Energy Technology Center (FETC) is conducting a research and development program geared towards establishing the technical, economic, and environmental feasibility of various carbon sequestration options.
For coal-fired utilities, CO2 sequestration in unmineable coal seams and depleted or abandoned oil and gas reservoirs may be the most attractive options. Coal resources in the U.S. are estimated to be over 6 trillion tons, and nearly 90 percent of coal is considered to be unmineable due to seam thickness, depth, and structural integrity. Limited field testing has shown that when CO2 is pumped into coal beds to displace entrapped natural gas, the CO2 is retained in the coal. With enormous coal resources located under or near existing fossil-fueled power plants, limited field demonstration of this approach for using coal as a geological sink for CO2 could demonstrate that this approach is very promising. Also, the proximity of coal-fired power plants to oil and gas producing regions enhances the potential of storing CO2 in depleted gas reservoirs or using the captured CO2 in enhanced oil recovery operations.
Deep ocean sequestration could be a useful option due to the enormous capacity of the oceans for CO2. Numerous environmental issues have been raised about the safety of this approach. These questions can only be answered by field tests. FETC is working with Japan and Norway, under an International Project Agreement to perform a field test that is likely to be conducted off the coast of Hawaii that will address technical and economic feasibility of this concept. Total project cost: FETC $850k, Japan - $2,600 k, and Norway - $350 k.
The FETC Carbon Sequestration R&D Program
Capture and Control
- Reduce the costs of capturing CO2 from coal combustion
- Evaluate the CO2 storage potential of oil and gas reservoirs
- Determine the feasibility of saline aquifers as potential CO2 storage sites
- Conduct field tests to determine the viability of storing CO2 in unmineable coal seams
- Investigate the formation of CO2 hydrates in deep ocean environments
- Determine the technical and environmental feasibility of injecting liquid CO2 into the ocean (joint program with Japan and Norway)
Enhanced Natural Sinks
- Conduct systems engineering and analysis on ocean fertilization to increase the uptake of atmospheric CO2
Novel Concepts
- Identify and develop "path-breaking" approaches to capturing, sequestering, and using or recycling CO2
- Award "Novel Concept" projects selected from a Program Research and Development Announcement to develop concepts from the conceptual stage through the pilot-scale. A large number of promising proposals are now being reviewed and awards are expected to be announced shortly. ($500 k in FY-98, up to $4,000 k in FY-99.)
Other Activities
- Demonstrate the technical feasibility of cofiring biomass with coal in existing power plants to reduce the net emissions of new carbon into the atmosphere, while maintaining the energy production capacity associated with coal-fired electric utilities. Some closed-loop biomass concepts also involve carbon sequestration in soil.
- Conduct research on zero-CO2 emissions advanced coal combustion concepts
Broad Participation of the Scientific and Industrial Community
FETC is sponsoring several workshops to bring together the best from academia and industry to advance the most promising R&D pathways and develop a roadmap that will make carbon sequestration a viable commercial technology. The first Workshop will be organized by MIT for FETC and will be held in Cambridge, Massachusetts on June 22 and 23, 1998. Subsequent Workshops on topics ranging from CO2 utilization to storage in geologic structures will be held later this year.
Summary
A robust portfolio of carbon management options is necessary to ensure the continued use of coal to generate electricity. FETC is poised to implement an extensive carbon sequestration program designed to provide several options to the utility industry. Carbon sequestration R&D is an appropriate federal R&D role--private industry cannot commit the required funding for possible emission regulations. Private industry realizes the potential of carbon management scenarios and is willing to support, and more importantly, participate in carbon sequestration R&D.
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