The Colstrip energy transition plan is centred on the 600MW Silverthorn wind project to be built across Rosebud and Treasure Counties in Montana, which is anticipated to interconnect at the Colstrip substation
Talen Energy Supply (TES) has signed a transaction with Puget Sound Energy (PSE) which will help advance the former’s implementation of the Colstrip energy transition plan in Montana, US.
As per the terms of the agreement, Talen Montana, which is an affiliate of Talen Energy Supply, will take over PSE’s 25% ownership stake in units 3 and 4 of the 1.48GW Colstrip coal-fired power station on 31 December 2025.
Talen Montana, which has a 30% ownership in unit 3 and no ownership in unit 4, is the operator of the power plant.
PSE will keep its share of environmental remediation as well as other asset retirement obligations, costs for decommissioning, and other appropriate costs pertaining to the two coal-fired units that accumulate till 31 December 2025.
Through the transaction, Talen Energy Supply wants to use the Colstrip power plant’s existing electric infrastructure for the development of utility scale renewables project. At the same time, the company’s decision is expected to help preserve resiliency of the grid for the Western Interconnect and deliver energy security among others.
Talen Energy Supply CEO Alejandro Hernandez said: “This strategic transaction is a tangible example of energy transition, balancing the interests of our various stakeholders and communities, while creating an attractive renewable energy investment opportunity for infrastructure capital partners.”
The Colstrip energy transition plan is centred on the new 600MW Silverthorn wind project to be built across Rosebud and Treasure Counties, which is anticipated to interconnect at the Colstrip substation.
The Silverthorn wind farm is part of a joint venture between Talen Energy Supply’s affiliate Cumulus Renewables and Pattern Energy Group. Subject to approvals, the wind farm is expected to begin commercial operations in 2026.
Silverthorn will complement the share of Talen Montana in the Colstrip units 3 and 4 by decreasing the overall carbon intensity of the company’s electric generation.
An investment of up to $1bn is expected to be made by Pattern Energy and Talen Energy Supply in the energy transition plan and the Silverthorn wind project.
Pattern Energy CEO Mike Garland said: “Our partnership with Talen Energy to facilitate the energy transition of Colstrip with our Silverthorn Wind project will make Colstrip one of the most important energy centres in the United States, serving the rapidly growing energy needs of the West.
“The Silverthorn project is of similar scale to our recent Western Spirit Wind facility with 1,050 megawatts of capacity, the largest wind power project ever constructed as a single phase in the Americas.”