Grid Mod: Capturing the impacts of the energy imbalance market on BPA’s transmission

For every entity in the Northwest wanting to participate in the Western Energy Imbalance Market, the path leads through the Bonneville Power Administration’s high voltage transmission system.

BPA recently completed a three-year project to formalize operations, control and data sharing between the power marketing agency and the California Independent System Operator to account for the impacts of EIM-related flows on the Federal Columbia River Transmission System.

“The tools implemented from the Coordinated Transmission Agreement project gives us confidence that the impacts of the EIM market on Bonneville’s transmission system are being actively monitored and controlled,” said Todd Kochheiser, an electrical engineer in Transmission Operations and the project manager for the CTA. “This helps ensure the reliability of the FCRTS, while enabling our customers and the region to access the EIM.”

In 2013, PacifiCorp announced that it would join the EIM. BPA began working with CAISO on how to account for EIM related flows and maintain reliability of the grid without negatively impacting BPA’s existing, non-EIM participating customers. 

“All of this work, for several years, was done on a hand shake and in good faith,” Kochheiser said.

BPA and CAISO began to negotiate a formal agreement in early 2016 as more entities in the Northwest sought to join the EIM resulting in a signed agreement in March 2017 and FERC approval in June 2017. 

“We were able to use that initial work as the foundation for a more robust agreement that clarified the obligations of each party,” said Michelle Cathcart, the vice president of Transmission System Operations for BPA. “With the CTA, we’ve been able to integrate new calculations and controls into our existing tool set to better manage real-time congestion on our transmission system.”

The CTA and its impact on congestion management were cited in supporting the decision to not build the massive I-5 Corridor Reinforcement Project between Longview, Washington, and Portland, Oregon.

A cross-functional team in Transmission implemented the technology, processes, and procedures supporting the CTA for BPA. 

As BPA considers joining the Western EIM, it is likely that certain aspects of the CTA will be revisited. 

“If we join the EIM, we will want to retain certain unique provisions and controls provided under the agreement,” Kochheiser said. “Other portions of the CTA may no longer be necessary in their current form and may be modified or replaced by other tools or processes available to EIM participants.”