Portland General Electric is now the second entity in the Western United States to sign an implementation agreement and formally commit to a regional day-ahead energy market with the California Independent System Operator for its Extended Day-Ahead Market.
The EDAM is a voluntary day-ahead electricity market designed to deliver reliability, economic, and environmental benefits to balancing areas and utilities throughout the West.
The remaining tariff changes allowing the EDAM were accepted by the Federal Energy Regulatory Commission in June, and the market is on track to become operational in 2026.
PGE serves 1.9 million customers in Oregon with a peak load of nearly 5,000 megawatts.
In March, it announced its intention to join the EDAM, extending the success of the ISO’s Western Energy Imbalance Market (WEIM), a real-time wholesale energy market that has produced cost savings to PGE customers and other market participants.
The WEIM optimizes energy imbalances throughout the West by transferring energy between participants in 15-minute and 5-minute intervals throughout the day, CAISO noted.
“The EDAM builds on this real-time market by expanding the commitment of least-cost generation across the market’s broad geographic footprint that are made a day in advance, unlocking far greater market efficiencies and value,” it said.
The implementation agreement is a provision of the ISO tariff and became effective upon the signing of both parties on June 28, 2024. PGE is expected to begin participating in the EDAM in fall 2026.
In addition to PGE, PacifiCorp has signed an agreement to begin participation in the EDAM in spring 2026.
Three additional entities have informed the ISO of their interest in joining the EDAM: Balancing Authority of Northern California, Los Angeles Department of Water & Power and NV Energy.
Idaho Power has said it is leaning toward the EDAM as its preferred day-ahead market.
