The Bonneville Power Administration (BPA) has proposed two transmission-line upgrades in Washington and Montana, which, combined with four new high-voltage lines already under construction or consideration, would deliver an additional 3,200 MW of electricity, including 1,900 MW of wind power.
The two new projects are the result of the BPA's network open season, a process to better gauge demand for new transmission and manage the BPA's transmission queue. The Northern Intertie Reinforcements would combine substation, line and other equipment upgrades to increase capacity on the BPA's interconnection with Canada. This effort includes a proposed transmission project involving Puget Sound Energy.
The Colstrip Upgrade project would combine system upgrades to increase transmission capacity in eastern Washington and Montana. It would allow the delivery of wind resources from Montana into the Northwest grid. The Colstrip project needs to be coordinated with a project planned by NorthWestern Energy to upgrade the Colstrip Transmission System further into Montana, according to the BPA.
While roughly half of this year's transmission service requests can be granted through the completion of the 2008 projects, the rest will require the two projects identified in the 2010 network open season. The 3,200 MW of new service equates to about triple the generating capacity of Bonneville Dam.
‘Most wind projects on the BPA system to date have been concentrated in the Columbia Gorge and nearby regions,’ says Brian Silverstein, senior vice president for the BPA's transmission services. ‘They tend to vary together, making balancing the wind a challenge. More geographic diversity in wind projects could make balancing easier.’
The BPA will now complete preliminary engineering and environmental review of the projects, which could take one to two years, and will then decide whether to proceed with the projects.