Dive Brief:
- Public Service Co. of New Mexico said Monday that it plans to join the California Independent System Operator’s extended day-ahead market, or EDAM, beginning in 2027. The market is slated to launch in the spring of 2026.
- The announcement is a win for EDAM over Southwest Power Pool’s competing Markets+, which is expected to launch in 2027.
- PNM already participates in CAISO’s Western Energy Imbalance Market, or WEIM, which the utility said has generated about $99 million in economic benefits for its customers since it joined in 2021. "Participating in EDAM is the next step in realizing the value of New Mexico's renewable energy potential for our customers,” PNM President and CEO Don Tarry said in a statement.
Dive Insight:
PNM is the latest utility to indicate it will join EDAM, after comparing potential benefits to SPP’s planned day-ahead market.
NV Energy over the summer chose to join EDAM over Markets+. And a Brattle study published in August concluded New Mexico utilities would see millions more in annual benefits by joining the CAISO market.
“The higher benefit in EDAM is largely driven by increased opportunities to execute market-to-market transactions,” Brattle said. The study pegged PNM’s potential annual benefits at $20.5 million if it participates in EDAM and $8 million in Markets+.
"We know from our experience with the WEIM – which has provided New Mexico customers nearly $125 million in benefits since we joined in 2021 – coordination with other regional utilities can deliver substantial efficiencies and cost benefits for our customers,” Tarry said.
Another New Mexico utility, El Paso Electric, has seen benefits of approximately $19 million since joining the WEIM in 2023, according to the New Mexico Public Regulation Commission.
The PRC held a series of workshops over the past year focused on the potential for electric utilities in the state to join regional markets. The commission last month issued a statement concluding the move “could benefit New Mexico’s ratepayers through cost savings and reliability enhancements.”
CAISO is "honored” that PNM announced its intent to join EDAM," Elliot Mainzer, CAISO president and CEO, said in a statement. "We look forward to building on the proven track record of the Western Energy Imbalance Market to deliver even greater economic and reliability benefits to PNM customers.”
Portland General Electric, Idaho Power, PacifiCorp, Los Angeles Department of Water and Power and the Balancing Area of Northern California, which includes the Sacramento Municipal Utility District, have also indicated they will participate in EDAM.
In April, SPP said more than two dozen western entities had indicated their support for continued development of Markets+.
