Portland-based PacifiCorp has just slipped into California’s high-stakes power game, becoming the first utility from outside the state to join the California Independent System Operator’s new Extended Day-Ahead Market. The market, known as EDAM, went live on May 1 and is built to coordinate day-ahead planning across a wider Western footprint to smooth out prices and shore up reliability. PacifiCorp says tapping a larger pool of generation and transmission should help cut costs for customers while making it easier to fold more renewable energy into the mix.
EDAM launches and who’s in
The May 1 go-live marked the first time organized day-ahead trading has stretched beyond California into the broader West, replacing some of the ad-hoc, last-minute scheduling that used to happen in real time. PacifiCorp said the market builds on the Western Energy Imbalance Market and will initially feature PacifiCorp as the inaugural non-California participant, with Portland General Electric set to join in October 2026 and several other entities already signed up for implementation in 2027 to 2028.
Why PacifiCorp moved
PacifiCorp executives say the math pencils out. After 90 days of running EDAM in parallel with its existing systems, the utility reported that the market’s price formation and expanded footprint met expectations and offered a way to trim unnecessary production costs. Utility Dive quoted PacifiCorp’s Mike Wilding saying that parallel operations gave the company confidence the market “is working as intended.” In utility-speak, that is about as close as you get to a high-five.
What it could mean for Oregon customers
Supporters of EDAM argue that a coordinated day-ahead market can lower bills by dispatching the cheapest available resources across a broad area, instead of each utility juggling its own portfolio in isolation. PacifiCorp has previously said its participation in Western markets delivered more than 1.1 billion dollars in benefits to its customers under the Western Energy Imbalance Market. The Oregonian/OregonLive reports that the company’s modeling suggests EDAM could add roughly 300 million dollars in savings, although the final tally will depend on future power prices, how transmission costs shake out, and the way resource adequacy rules are handled.
A tug of war over which market the Northwest prefers
Not everyone in the Pacific Northwest is lining up behind EDAM. The Bonneville Power Administration has pursued the Southwest Power Pool’s Markets+ option instead and has laid plans to implement it, arguing that Markets+ does a better job of protecting the federal hydropower system’s interests. BPA outlined its Markets+ policy in 2025, and in late April several utilities, including Portland General Electric, joined a petition for review in the Ninth Circuit challenging BPA’s chosen path. PGE filings show that the utility and others have already moved to seek judicial review, setting the stage for a legal and regulatory tug of war over which market design wins out in the region.
What to watch next
With EDAM now up and running, the California Independent System Operator and market participants say they will be watching several pressure points closely, including price formation, transmission access charges and the new imbalance-reserve product. They expect to refine the rules through stakeholder processes and the newly formed Regional Organization for Western Energy. CAISO and other market observers caution that the first months of operation will likely reveal kinks that need fixing, so the modeled benefits may take a while to show up in the form of smaller numbers on customers’ bills.
