PacifiCorp has signed an implementation agreement with the California ISO for its Extended Day-Ahead Market (EDAM), a voluntary day-ahead electricity market designed to deliver significant reliability, economic, and environmental benefits to balancing areas and utilities throughout the West.
The agreement is a provision of the ISO tariff. PacifiCorp is expected to start participation in the EDAM in spring 2026. While tariff changes allowing the EDAM are approved by the Federal Energy Regulatory Commission, the market is expected to be operational in 2026.
PacifiCorp intends to join the EDAM to expand on benefits it realizes from participation in the ISO’s real-time Western Energy Imbalance Market (WEIM).
The proposed EDAM builds on real-time market by expanding to a high volume of resource commitments made a day in advance, revealing greater market efficiencies and value.
“A modern, coordinated day-ahead market in the West is vital to optimizing the region’s energy resources so we can continue to provide reliable and affordable power to our 2 million electricity customers across six states,” said Cindy Crane, chief executive officer for PacifiCorp.
While four entities namely PacifiCorp, Balancing Authority of Northern California, Portland General Electric and Los Angeles Department of Water & Power have informed the ISO of their interest in joining the EDAM, a fifth entity, Idaho Power has also indicated connecting the EDAM as its preferred day-ahead market.
“This is a major piece of a truly collaborative effort to support reliability and affordability for electricity customers by leveraging resource diversity and transmission connectivity across the footprint of the Western grid,” said Elliot Mainzer, president and CEO of the ISO. “We now look forward to continue working with additional valued partners in the West to take the next steps in a fully integrated regional market.”
