New transmission path supports Portland's growing energy demands, enables new contracts

Managing Portland area transmission congestion just got easier.

Last year, BPA achieved a significant milestone with the implementation of a new transmission path that enables the agency to better manage transmission congestion in the greater Portland-Vancouver area. With this change, BPA can more accurately determine how much transmission is in use at any time, and, if needed, take more precise precautionary measures to keep the grid operating reliably.

The new path, named North of Pearl, addresses the area’s growing energy demands as well as the ability to support new renewable generation coming online. A new transmission path doesn’t mean new construction. Instead, it identifies a certain group of existing lines that if observed collectively will enable transmission operators to better observe the flow of electricity on that path, providing greater insight and control opportunities during high demand.

The new path provides BPA an efficient way to improve energy flows and alleviate congestion on its transmission system around the Portland metropolitan area. Transmission congestion typically occurs when a transmission line is unable to carry additional electric flows due to the risk of overheating, equipment failure or other reliability issues. These problems can quickly multiply when the region experiences extreme temperatures, increasing load on the grid, as was the case on Aug. 14, 2023, when the temperature soared to 108 degrees in Portland.

To address congestion effectively, BPA’s transmission operators employ multiple options to find the most efficient way to handle transmission overload. These options include rerouting energy deliveries, reducing generator output, reducing transmission schedules – also known as curtailing – or using more manual options such as substation switching, which is generally less desirable due to wear and tear on equipment.

BPA routinely monitors certain existing transmission lines and substations collectively to analyze where congestion exists and how much surplus transmission is available to be sold for future use. These transmission facilities are commonly referred to as “paths” and are central to how BPA models energy flows on the grid. After completing multiple system studies in 2022, BPA determined the current paths used for modeling and managing grid conditions in the Portland area were insufficient and a new path was needed.

Creating a new path entails the collaboration of various organizations across Transmission Services, involving complex tasks such as performing technical studies, updating operational procedures and BPA’s scheduling platform as well as reaching out to impacted customers, executing transmission contracts, and finally, implementing the program. In November 2023, BPA implemented the North of Pearl path after two demanding years of work by staff.

“Adding North of Pearl allows operations to manage Hillsboro area congestion as the emergence of intermittent resources and rapid load growth changes flows on the system,” said Ricky Bustamante, vice president of Transmission System Operations. “The new path also enabled BPA to make new transmission sales in response to customer demand. I’m so proud of the collaboration and ‘consider it done’ approach the team used.”

Implementation of the North of Pearl path is one example of BPA making good on its commitments in the 2023-2028 Strategic Plan. BPA is committed to improve operations that support grid reliability and continue to maximize the capacity of the existing grid through a combination of operational studies, visualization tools, congestion management and other operational updates. As BPA enters 2024, it will identify and implement transmission solutions that create the most value for the region.

“The new path provides BPA additional capacity to support transmission service for five customers. Providing this additional service would generate $30 million per year in revenue for BPA without new infrastructure,” said Natasha Bryan, Conditional Firm Program manager. “This supports the agency’s financial health while also putting downward pressure on transmission rates.”

The successful creation of the North of Pearl path was a cross-agency effort. While Transmission Planning and Transmission System Operations performed much of the technical work, the implementation team included staff from Power Generation, Transmission Engineering, Transmission Technology, Transmission Field Services and Transmission Marketing and Sales.