CHEYENNE — The Wyoming Public Service Commission has ordered an investigation into Rocky Mountain Power’s plans that include the early retirement of coal-fired plant units in Southwest Wyoming.
The integrated resource plan (IRP) released by Rocky Mountain Power in October includes a preferred portfolio and action plan detailing the company’s intentions to move toward wind, solar and battery resources, with the retirement of units at Jim Bridger Power Plant near Rock Springs and the Naughton Plant near Kemmerer.
On Nov. 13, Wyoming’s Public Service Commission issued an order to initiate an investigation to evaluate the IRP, preferred portfolio and action plan to “ensure they are economically justified,” according to documents. The action came after a Nov. 7 commission meeting.
WyoFile reported in September that a company analysis estimated PacifiCorp and its 1.9 million utility customers could save up to $599 million by retiring several coal-fired electrical generating units in Wyoming and elsewhere — including early closures at the Jim Bridger and Naughton plants.
Rocky Mountain Power’s plans include the retirement of all of Jim Bridger Power Plants coal-fired units by 2037. Under the preferred portfolio of PacifiCorp’s integrated resource plan, Jim Bridger Unit 1 will close by the end of December 2023, Unit 2 will close by 2028 and Units 3 and 4 will operate through 2037.
The commission’s order set three public comment hearings on the issue. The Rock Springs hearing is scheduled from 11 a.m. to 2 p.m. on Jan. 29, 2019 at Rock Springs City Hall, 212 D St. Kemmerer’s hearing will be from 4-7 p.m. on Jan. 28, 2020 at its City Council chambers, 220 Wyoming Highway 233. There will also be a public hearing May 5-6, 2020, in the commission’s hearing room in Cheyenne.
In its order, the commission said, “Any decision to retire coal-fired generation units prior to the end of their established depreciable lives may adversely impact the cost and reliability of service provided to RMP’s Wyoming customers while producing significant negative economic impacts. These impacts, individually and collectively, must be thoroughly evaluated to ensure implementation of the preferred portfolio is consistent with the public interest.”
According to the draft action plan, PacifiCorp also plans to retire Naughton Units 1 and 2 and Craig Unit 1 by the end of December 2025. The plan also proposes converting the previously closed Naughton Unit 3 in Kemmerer to natural gas, and constructing a 400-mile transmission line from the Aeolus substation near Medicine Bow to the Clover substation near Mona, Utah, along with additional transmission upgrades.