Extended Day-Ahead Market Expanded to include Portland General Electric
Portland General Electric (PGE), Oregon's largest electric utility serving nearly one million customers, has officially begun participation in the California Independent System Operator's (ISO) Extended Day-Ahead Market (EDAM), expanding access to affordable, reliable and clean energy resources for its customers and across the West.
EDAM allows participating utilities to buy and sell energy in the day-ahead timeframe, where most electricity transactions occur. EDAM also enables more efficient use of the diverse energy resources available across the West, including hydropower and wind from the Pacific Northwest and solar generation from California and the desert Southwest.
By optimizing supply, demand and transmission across a broader geographic footprint, the market helps lower costs, improves reliability and supports greater use of renewable energy.
"We worked closely with the California ISO and partners throughout the West to design a day-ahead market that delivers real value to customers," said Maria Pope, president and CEO of Portland General Electric. "EDAM gives us access to a broader portfolio of resources across the West, helping us manage costs, enhance reliability and support Oregon's clean energy future."
PGE has participated in the ISO's Western Energy Imbalance Market (WEIM) since 2017, reporting approximately $377 million in cumulative benefits for the company and its customers during that time. Overall, since the market launched in 2014, WEIM has grown to include 24 balancing authorities serving nearly 80 percent of electricity demand in the West and resulting in more than $9 billion in financial savings. EDAM went live in May, generating more than $11 million in initial benefits for participating entities and their customers during the market’s first two months of operation.
"PGE's participation reflects the growing momentum behind regional market collaboration in the West," said Elliot Mainzer, president and CEO of the California ISO. "The addition of PGE expands resource diversity and strengthens the market's ability to deliver economic and reliability benefits to participants and their customers."
EDAM launched May 1 with the ISO and PacifiCorp's two balancing authority areas. Since then, PacifiCorp is already delivering value for its customers through its market participation.
“EDAM is already delivering meaningful value for PacifiCorp and its customers, including $5.42 million in gross benefits during the market’s first two months,” said Ryan Flynn, president of Pacific Power. “We are encouraged by the strong start, and excited about Portland General Electric’s participation and what deeper regional partnership can achieve for customers and the communities we serve.”
Additional utilities are scheduled to join beginning in 2027, including the Los Angeles Department of Water and Power, the Balancing Authority of Northern California, the Public Service Company of New Mexico and Turlock Irrigation District. The Imperial Irrigation District, BHE Montana and NV Energy have committed to join in 2028.
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About Portland General Electric Company
Portland General Electric (PGE) is an integrated energy company that generates, transmits and distributes electricity to over 930,000 customers serving an area of 1.9 million Oregonians. For more than 130 years, PGE has powered social progress, delivering safe, affordable, reliable and increasingly clean electricity while working to transform energy systems to meet evolving customer needs. PGE customers have set the standard for prioritizing clean energy with the No. 1 voluntary renewable energy program in the country. PGE is committed to reducing emissions from its retail power supply by 80% by 2030 and 100% by 2040. PGE is recognized by the Bloomberg Gender-Equality Index for the company's commitment to creating a more equal, inclusive workplace. In 2023, PGE employees, retirees and the PGE Foundation donated nearly $4.6 million and volunteered over 23,000 volunteer hours to more than 400 nonprofit organizations.
About PacifiCorp
PacifiCorp is one of the lowest-cost electrical providers in the United States, serving two million customers. The company operates as Rocky Mountain Power in Idaho, Utah and Wyoming and as Pacific Power in California, Oregon and Washington. PacifiCorp provides safe and reliable service through a vast, integrated system of generation and transmission that connects communities as the largest regulated utility owner of wind power in the West. For more information, visit PacifiCorp.com.
About the California ISO
The California Independent System Operator (ISO) is a nonprofit public-benefit corporation responsible for the reliable operation of California’s bulk electric grid. The ISO provides transmission planning, open and nondiscriminatory access to one of the world's largest high-voltage transmission networks and operates competitive wholesale electricity markets for the benefit of consumers.
About the Western Energy Markets
The Western Energy Markets include the Western Energy Imbalance Market (WEIM) and the Extended Day-Ahead Market (EDAM), which provide regional market coordination across the West. The WEIM, launched in 2014, helps participants balance electricity supply and demand in real time and has delivered billions in benefits to market participants and their customers. EDAM began operation in 2026 and extends those benefits into the day-ahead timeframe through broader regional coordination. The Western Energy Markets Governing Body has primary decision-making authority over market rules specific to the WEIM and EDAM.