Wyoming commission approves SCR for two Bridger coal units

The Wyoming Public Service Commission on May 29 approved a Certificate of Public Convenience and Necessity (CPCN) for Rocky Mountain Power for the construction of selective catalytic reduction systems (SCR) on the coal-fired Jim Bridger Units 3 and 4.

The Jim Bridger plant is located near Point of Rocks, Wyo., and is two thirds owned by PacifiCorp d/b/a Rocky Mountain Power (RMP), and one-third owned by Idaho Power. Those two parties also co-own in those same proportions adjacent surface and deep coal mines that supply the plant with much of its coal. The plant’s generating capability is 2,120 MW, with 1,411 MW of that controlled by RMP.

In August 2012, RMP filed its application with the commission. During the course of the case, the Sierra Club contended that the commission should deny RMP’s application as premature because the U.S. Environmental Protection Agency had not yet issued its final decision on the Wyoming State Implementation Plan and the regional haze environmental controls that will be required at Bridger.  The Sierra Club asserted the application should address all four units at Bridger after all of the requirements of the federal Best Available Retrofit Technology (BART) determinations under the regional haze rule are finally known.

The controls on Bridger Units 3 and 4 stem from a determination that these units must use BART as part of the state’s plan. The technology proposed in this case, SCR, was chosen following a lengthy and complex process of analysis. The two principal alternatives to installation of the SCR were converting Bridger Units 3 and 4 to natural gas, or retiring them early and replacing their capacity with alternative resource options, the PSC noted.

PacifiCorp has several clean-air projects in the works

The Bridger SCRs are part of an overall coal compliance plan. PacifiCorp plans to convert the coal-fired Naughton Unit 3 in Wyoming to a natural gas-fired facility and to install environmental investments required to meet near-term compliance obligations at the Hunter Unit 1 in Utah and Jim Bridger Units 3 and 4.

“Installation of emission control equipment at these facilities will reduce emissions of nitrous oxides (NOX) and sulfur dioxide (SO2) and contribute to improved visibility in the region,” PacifiCorp added in an integrated resource plan (IRP) filed April 30 at the Utah Public Service Commission. “The Company plans to continue to evaluate environmental investments required to meet known and prospective environmental compliance obligations at existing coal units in future IRPs and future IRP Updates.”

The coal-related action plan includes:

  • Naughton Unit 3 (Wyoming, 330 MW) – Continue permitting and development efforts in support of the Naughton Unit 3 natural gas conversion project. The permit application requesting operation on coal through year-end 2017 has been under review by the Wyoming  Department of Environmental Quality, Air Quality Division. Issue a request for proposal to procure gas transportation for the Naughton plant as required to support compliance with the conversion date that will be established during the permitting process. Issue an RFP for engineering, procurement, and construction of the Naughton Unit 3 natural gas retrofit as required to support compliance with the conversion date that will be established during the permitting process.
  • Hunter Unit 1 (Utah, 418 MW) – Complete installation of the baghouse conversion and low NOX burner compliance projects at Hunter Unit 1 as required by the end of 2014.
  • Jim Bridger Units 3 and 4 (Wyoming, 702 MW total) – Complete installation of SCR projects at Units 3 and 4 by the end of 2015 and 2016, respectively.
  • Cholla Unit 4 (Arizona, 387 MW) – Continue to evaluate alternative compliance strategies that will meet regional haze obligations, related to EPA’s Federal Implementation Plan requirements to install SCR equipment at Cholla Unit 4.
About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.