Arizona Public Service and Puget Sound Energy have moved a step closer to linking up with CAISO’s Energy Imbalance Market (EIM).

CAISO provided stakeholders an update on its efforts to address Air Resources Board (ARB) concerns that the EIM is not properly accounting for the impact of emissions.

The western Energy Imbalance Market continued to boost demand for California’s surplus renewable generation last quarter.

Critics say CAISO is moving too quickly in its effort to get a plan for a Western RTO to California lawmakers before legislative session's end.

CAISO released a revised set of principles for governing a Western RTO in a bid to convince skeptics that an expanded ISO will be amenable to the entire region.

Utah lawmakers plan to draft a bill requiring PacifiCorp to gain legislative approval before joining an RTO based on an expanded CAISO.

FERC rejected the CAISO proposal to prohibit EIM participants from implementing economic bidding at the market’s external interties.

The CAISO Board of Governors appointed five members to the newly established governing body of the western Energy Imbalance Market (EIM).

CAISO stepped up efforts to convert skeptics of a Western RTO, convening a forum in Denver to discuss a proposed set of governing principles.

CAISO's Department of Market Monitoring reported that solar power surpassed wind in 2015, becoming the largest source of renewable generation.