The dominant use of coal in the United States today is for electric power generation based on the combustion of pulverized coal. As a result of regulatory programs over the past two decades, substantial progress has been made toward the control of emissions of air pollutants and other wastes that can harm human health (EPA, 2007). Federal R&D programs concerned with coal use are focused on developing more cost-effective technologies to enable coal-based power plants to meet environmental constraints.
Emissions of CO2 from coal-based power plants are not currently subject to regulation or controls. However, low-emission coal-based power plants equipped with technologies for the capture and geological sequestration of CO2 are projected to be developed to the point of commercial readiness by 2015 as part of DOE’s Carbon Sequestration Program. Currently, however, there are no full-scale demonstration projects of CO2 capture and storage at a large, modern coal-based power plant.
The following principal findings have resulted from this brief review of coal utilization issues:
Potential regulatory requirements to further reduce emissions of NOx, SO2, mercury, and particulate matter in the future are not expected to significantly limit the overall use of coal in the next several decades. However, future emission control requirements for these regulated air pollutants could result in changed preferences for particular types of coal, depending on the nature of future regulations.
Decisions to invest or not invest in coal-based power plants will strongly influence future coal use, and this will depend in large part on both the timing and the magnitude of any future constraints on CO2 emissions, as well as on the demonstrated commercial readiness of technologies to significantly reduce CO2 emissions from coal-based power plants and other energy conversion processes.
Detailed assessments are needed to identify and characterize potential geological formations in the United States that are capable of sequestering large quantities of CO2; to quantify their storage capacities; to assess migration and leakage rates; and to understand the economic, legal, and environmental impacts of storage on both near-term and long-term time scales. Such geologic sequestration sites should be considered “resources,” and categorized and described in the same way that conventional mineral or energy resources are assessed.
Recommendation: The U.S. Geological Survey (USGS) should play a lead role in identifying, characterizing, and cataloguing the CO2sequestration capacity of potential geologic sequestration resources.