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Clean Air Markets

Analysis of the Proposed ACE Rule

On August 21, 2018, EPA proposed the Affordable Clean Energy (ACE) rule.  EPA's power sector analysis for this proposal uses EPA’s Power Sector Modeling Platform v6 using IPM.

Supplemental Documentation for Analysis of the Proposed ACE Rule

For the power-sector analysis of the proposed ACE rule, the EPA used an earlier version of the model that is slightly different than the version documented on EPA’s Power Sector Modeling Platform v6 using IPM website. To learn more about these differences, see the Incremental Documentation for EPA Platform v6 used for the Proposed ACE Rule. This supplemental documentation complements more comprehensive modeling documentation available at EPA’s Power Sector Modeling Platform v6 using IPM.

Below is the version of NEEDS used for the analysis of the proposed ACE rule.

IPM Run Files

Download IPM run files for the proposed ACE rule using the links in the table below. Click on the IPM run name in the first column of the table below to download a file. The files are posted in one of two formats, a zipped archive or an excel spreadsheet, and contain detailed IPM input and output files (i.e., .DAT, System Summary Report, .RPE, and RPT files) for the listed runs. More detailed information on the modeling framework, specific scenarios, assumptions, and other important details of the analysis can be found in the Regulatory Impact Analysis that accompanies the proposed ACE rule.

  • To facilitate the output visualization of the results, a Results Viewer(9 pp, 34 MB, Sept 10, 2018) is available to compare these different scenario projections and link them with historical data.

IPM Run Name IPM Run Description
Base Case Scenario (CPP) (6 pp, 143 MB) This scenario includes the Clean Power Plan (CPP) modeled in a similar fashion to previous EPA analytical efforts. More specifically, this scenario utilizes a mass-based implementation of CPP at the state level, with intra-state trading covering existing sources only, and no incremental demand-side energy efficiency investments. In this scenario, coal steam units may choose to adopt technologies that achieve a 2.1 percent to 4.3 percent HRI at a capital cost of $100/kW based on prevailing economics, but are not required to do so given the flexible compliance afforded under CPP. The improvement and cost level of HRI in this scenario is consistent with the assumptions regarding the availability and cost of HRI used to develop building block 1 in the final CPP, and is the same level applied in the final RIA for the CPP (U.S. EPA, 2015a). In this RIA, this scenario represents the primary electricity and related fuel market baseline for comparison with the three illustrative policy scenarios below.
Illustrative 2 percent HRI at $50/kW Scenario (6 pp, 133 MB)

This illustrative scenario represents a policy case that reflects modest improvements in HRI absent any revisions to NSR requirements. This scenario assumes a uniform potential HRI is available for all affected sources. In the model, this scenario requires a source to improve its heat rate by 2 percent, at a capital cost of $50/kW. The source can either adopt the improvement or retire, based upon the prevailing economics in the model.

Illustrative 4.5 percent HRI at $50/kW Scenario (6 pp, 133 MB) This illustrative scenario represents a policy case that includes benefits from the proposed revisions to NSR, with the HRI modeled at a low cost. This scenario assumes a uniform potential HRI is available for all affected sources. In the model, this scenario requires a source to improve its heat rate by 4.5 percent, at a capital cost of $50/kW. The source can either adopt the improvement or retire, based upon the prevailing economics in the model.
Illustrative 4.5 percent HRI at $100/kW Scenario(6 pp, 133 MB) This illustrative scenario represents a policy case that includes the benefits from the proposed revisions to NSR, with the HRI modeled at a higher cost. This scenario assumes a uniform potential HRI is available for all affected sources. In the model, this scenario requires a source to improve its heat rate by 4.5 percent, at a capital cost of $100/kW. The source can either adopt the improvement or retire, based upon the prevailing economics in the model.
Illustrative No CPP Scenario(6 pp, 133 MB) This illustrative scenario does not apply any standards of performance under section 111(d) of the CAA for CO2 emissions from existing sources. Furthermore, in this scenario, it is assumed that no source adopts any heat rate improvements.
Base Case Scenario (CPP) with EE(6 pp, 142 MB) This scenario includes the Clean Power Plan (CPP) modeled in a similar fashion to previous EPA analytical efforts. More specifically, this scenario utilizes a mass-based implementation of CPP at the state level, with intra-state trading covering existing sources only, and incremental demand-side energy efficiency investments. In this scenario, coal steam units may choose to adopt technologies that achieve a 2.1 percent to 4.3 percent HRI at a capital cost of $100/kW based on prevailing economics, but are not required to do so given the flexible compliance afforded under CPP. The improvement and cost level of HRI in this scenario is consistent with the assumptions regarding the availability and cost of HRI used to develop building block 1 in the final CPP, and is the same level applied in the final RIA for the CPP (U.S. EPA, 2015a). In this RIA, this scenario represents the primary electricity and related fuel market baseline for comparison with the three illustrative policy scenarios below.