The Western EIM took on BPA and Tucson Electric Power as new participants, marking the market’s largest single expansion since its founding.

CAISO's Western Energy Imbalance Market surpassed $2 billion in total member benefits only 20 months after hitting the $1 billion mark in 2020.

The Bonneville Power Administration is on target to enter the Western EIM in early May after executives made a final determination on its market readiness.

SPP said it plans to close its Western Energy Imbalance Service, with members joining either its proposed Markets+ program or its Western RTO.

A CAISO market report says high natural gas prices drove a 50% run-up in electricity costs in Q4 2021, hitting the Western Energy Imbalance Market as well.

BPA is on track to enter the Western Energy Imbalance Market on May 3, despite lingering issues with software systems related to market integration.

CAISO's Board of Governors and the Western Energy Imbalance Governing Body adopted changes to WEIM's resource sufficiency evaluation for market participants.

CAISO's Western Energy Imbalance Market hit a record $739 million in member benefits in 2021, putting its total close to $2 billion since it launched in 2014.

Washington utilities Avista and Tacoma Power will not delay their entry into the Western EIM, despite BPA’s decision to postpone joining by two months.

The Bonneville Power Administration said it will delay its entry into the Western EIM by two months to work out technical and training issues.