April 14, 2015



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PacifiCorp/ISO Memorandum of Understanding to Explore Full PacifiCorp Participation




The California Independent System Operator (ISO) and PacifiCorp entered into a Memorandum of Understanding to explore the feasibility, costs and benefits of PacifiCorp joining as a Participating Transmission Owner.  A comprehensive benefits study is underway.  If additional steps are taken to pursue joining the ISO, stakeholder processes will be initiated.



Main Text

The California Independent System Operator (ISO) and PacifiCorp announced today that they have entered into a Memorandum of Understanding (MOU) to explore the feasibility, costs and benefits of PacifiCorp joining the ISO Balancing Authority Area as a Participating Transmission Owner.


A comprehensive benefits study is underway that is expected to be completed this summer.  Should PacifiCorp decide to take additional steps to pursue joining the ISO, the organizations will initiate stakeholder processes to review and develop rules and procedures for the proposed project consistent with the principles outlined in the MOU.  Any eventual decision by PacifiCorp to join the ISO applies only to the two balancing authority areas operated by PacifiCorp, and is subject to review and approval by PacifiCorp's six-state utility commissions and by the FERC.


The organizations believe there are substantial mutual benefits associated with full participation:

Enhanced coordination and day-ahead optimization across a broad geographic area.

Coordinated planning and utilization of the two largest transmission systems in the West.

Lower carbon emissions and more efficient use and integration of renewable energy resources.

Enhanced reliability through broader visibility across the combined systems and better planning and management of congestion across more of the region's high-voltage transmission system.


The ISO and PacifiCorp recognize that there are a number of complex policy questions to resolve that will require engagement and collaboration with numerous stakeholders:

Review of the governance structure due to operations across a multi-state footprint.

Explore alternate transmission access charge structures for regional transmission projects.

Adapt resource adequacy requirements.

Expand ISO transmission planning process to include PacifiCorp area, engage state commissions.

Merge generator interconnection queues.


This announcement will not impact the existing Energy Imbalance Market (EIM) for current or future EIM participants.  EIM remains open for new participants and will continue to provide important opportunities for cost savings and reliability improvements.


If decision is made to proceed, the organizations believe a transition date could occur in 2017.


Read the news release issued today here:


The MOU and Frequently Asked Questions are available on the ISO website at



For More Information Contact

Steven Greenlee at


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