PSE IN MONTANA:
THE COLSTRIP TRANSMISSION SYSTEM
The Colstrip Transmission System was built in the early 1980s to move power from the Colstrip generating facilities to transmission systems in western Montana. The Colstrip Transmission System is jointly owned by NorthWestern Energy, Avista Corporation, Portland General Electric, Puget Sound Energy, and PacifiCorp.
The Colstrip system is made up of two 500 kilovolt segments. The first runs from Colstrip to Broadview and the second runs from Broadview to Townsend. At present, power from the Colstrip Transmission System moves across the Bonneville Power Administration’s (BPA) transmission system west of Townsend before reaching local utility customers and BPA’s main grid.
PLANNING FOR THE FUTURE
As a Washington-state based utility, PSE must plan to meet the requirements of the Clean Energy Transformation Act, which require electric utilities to transition to a carbon-neutral supply of electricity
There is significant interest in developing electric generation resources in Montana and already there have been several agreements for new renewables to interconnect to the Colstrip Transmission System. PSE is committed to investing in Montana’s “all of the above” energy economy and has already taken steps in investing in new wind in Montana through the development of the Beaver Creek Wind Project as well as power purchase agreements.
Access to available transmission capacity can only be obtained by following the Federal Energy Regulatory Commission (FERC) rules. Additionally, access would need to meet requirements under the Montana Intertie Agreement and its successor arrangements upon renewal. The Colstrip Transmission System operator (i.e., NorthWestern Energy) conducts transmission and interconnection studies (on behalf of and in consultation with the Colstrip Transmission System owners) under the Open Access Transmission Tariffs (OATTs) of the Colstrip Transmission System owners (and the Colstrip Transmission Agreement) in response to requests for interconnection and transmission service on the Colstrip Transmission System for specific new generation.
The following map outlines how PSE’s current Montana resources are entering the transmission system:
