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Wind and the Environment: The EPA's Tech Divide
Does the Clean Air Act require the agency to consider the most low-emission coal plant technologies in permitting new plants?
In December 2005, the United States Environmental Protection Agency (EPA) announced that an applicant seeking a permit to construct a supercritical pulverized coal (SCPC) electricity generating facility in an attainment area need not consider integrated gasification combined-cycle (IGCC) technology under a Clean Air Act (CAA) analysis of best available control technology (BACT).
The EPA’s determination is important in several respects. First, its conclusion diverges from determinations by several states that, under either federal or state clean air provisions, IGCC must be considered in a BACT analysis for an SCPC power plant. Other states continue to consider the issue, and the EPA’s determination arguably dissuades these states from considering IGCC.
Moreover, the EPA’s announcement is particularly significant in light of the need to replace aging plants and create new energy generation capacity. 1 As these companies seek permits to construct their new plants, they are likely to find increased support—on grounds of cost and reliability of established technology—for their contentions that they should be permitted to pursue projects that do not use IGCC.
At the same time, the promise of IGCC to enable sequestration of carbon dioxide, a greenhouse gas, strongly motivates environmental advocates to move IGCC technology forward during this limited window of opportunity.
The EPA’s Position
In a Dec. 13, 2005, letter, Stephen Page, director of the EPA’s Office of Air Quality, Planning, and Standards, responded to a request by a Colorado energy consultant for the EPA’s position on whether a BACT analysis for proposed coal-fired power plants must include an evaluation of IGCC. 2 According to the EPA, Congress intended to distinguish between “production processes and methods, systems, and techniques” potentially applicable to a facility from those “alternatives” to the proposal that “would wholly replace the proposed facility with a different type of facility.” 3
The EPA determined that IGCC would redefine the basic design of an SCPC for the following reasons: (1) aspects of the IGCC technology are similar to designs previously deemed redefinitions of SCPC facilities; (2) the turbine and heat recovery system in an IGCC facility is akin to that found in a natural-gas plant rather than a traditional SCPC facility; (3) IGCC is more like technology used in refining and chemical manufacturing processes rather than power generation plants ( i.e., controlled chemical reaction rather than true combustion); and (4) the IGCC technology would require different expertise on the part of the permit applicant as compared with the knowledge required for an SCPC unit. 4 Thus, in determining that IGCC technology would redefine a proposed SCPC project, the EPA surmised that Congress did not intend to require consideration of IGCC in a BACT analysis.
The EPA did, however, note in its letter that, under Section 165(a)(2), the permitting