Wyoming panel hears that Rocky Mountain Power customers face multiple rate increases starting July 1

The interim Corporations, Elections & Political Subdivisions Committee on Wednesday heard officials warn of near‑term rate pressure for Wyoming electricity customers.

Abby Briggemann, an attorney with Holland & Hart representing the Wyoming Industrial Energy Consumers, told the committee the energy cost adjustment mechanism (ECAM) Rocky Mountain Power recently filed will raise the average Wyoming ratepayer’s bill by 12.3% on July 1. She added that the expiration of federal corporate tax credits will produce an additional average increase of 4.2% the same day, and “taken together, the average Rocky Mountain Power rate payer will see their rates increase by 16.5%.”

The Wyoming Public Service Commission said such adjustments recover prudently incurred power costs outside of a utility general rate case and are handled through an annual proceeding. PSC staff also told legislators that utilities retain an 80/20 sharing band on some power‑cost adjustments, and that the commission will scrutinize the filing.

Rick Casen of Rocky Mountain Power described a complex set of cost drivers: purchased power and volatile fuel prices, inflation and higher interest rates for financing, higher labor costs, supply‑chain delays and demand growth driven by data centers and artificial‑intelligence workloads. Casen said such elements make it difficult to isolate a single cause for rising retail bills.

Committee members also questioned the potential rate impact of multi‑state transmission projects. Legislators referenced an $8 billion figure circulating for new transmission used to move Wyoming‑sourced renewables west; PSC and company representatives said any cost recovery for such interstate projects would be addressed in future base‑rate proceedings and allocation work for multistate protocols would determine how much Wyoming customers ultimately pay.

The committee did not take formal votes but directed staff and the PSC to continue providing technical briefings to members during the interim. Lawmakers asked utilities and the PSC to provide more localized affordability data and to refine estimates of potential transmission cost allocation before any base‑rate filings.