New Members Successfully Integrated into Northwest Power Pool Reserve Sharing Group

May 28, 2024, 9:31 a.m. by ChaRee DiFabio | Last modified May 28, 2024, 9:38 a.m.

Yearlong ‘tremendous’ effort culminates in cutover on May 1

PORTLAND, Ore. – After a yearlong complex implementation effort, 10 new members successfully joined operations of the Northwest Power Pool Reserve Sharing Group on May 1.

The new participants are former members of the Southwest Reserve Sharing Group, coming from Arizona, New Mexico, Southern Nevada, California’s Imperial Valley and Texas. They reached an agreement in June 2023 to join the NWPP Reserve Sharing Group, which had 20 existing participants spanning much of the Pacific Northwest and parts of Canada.

The expanded contingency reserve program now includes all balancing authorities in the Western Interconnect except CAISO, LADWP and CFE.

Since the agreement was made last year, there has been a significant amount of work behind the scenes to integrate the new participants. The collaboration included the existing members of the Reserve Sharing Group, the incoming members, and staff from the Western Power Pool, which operates the program.

“We recognize and appreciate the tremendous effort from everyone involved to get to this milestone, from each of the participants to the members of our team,” said ChaRee DiFabio, Reserve Sharing Group Committee Manager for Western Power Pool.

According to DiFabio, the process involved a number of logistical and technical steps, such as establishing real-time communications with the new members and programming to incorporate RSG functionality into their energy management systems. There were also multiple rounds of training, both on-site and virtual, and on-site testing at each new member’s location.

Balancing authorities are required by reliability organizations like NERC and WECC to have contingency reserves available to respond to an unexpected event, like the loss of a generator. A reserve sharing program allows members to pool their reserves so they can all meet their individual mandated requirements with fewer overall resources. It’s like a joint savings account that all members can tap into for emergencies.

“The benefits of a contingency reserve sharing program increase exponentially with more members, a larger geographic footprint and more diverse resources,” DiFabio said. “Broad regional collaboration is one of the most important tools we have to help ensure reliability in the West.”

The new Reserve Sharing Group members are:

  • Arizona Public Service Company
  • Arlington Valley, LLC
  • El Paso Electric Company
  • Griffith Energy, LLC
  • Imperial Irrigation District
  • New Harquahala Generating Company, LLC
  • Public Service Company of New Mexico
  • Salt River Project
  • Tucson Electric Power
  • WAPA - Desert Southwest Region

As of May 1, they have officially joined the Reserve Sharing Group Committee (RSGC) and Operating Committee, as well as the Reserve Sharing Program.

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