The Western Area Power Administration said Oct. 30 that its Sierra Nevada (SN) region will pursue “final negotiations” to join CAISO’s Extended Day-Ahead Market (EDAM), notching another — if expected — victory for the ISO in its competition with SPP’s Markets+.
SN already participates in CAISO’s Western Energy Imbalance Market (WEIM) through its membership in the Balancing Authority of Northern California (BANC).
BANC and its largest member, Sacramento Municipal Utility District, were last year among the first entities to announce their intent to pursue membership in the EDAM, after PacifiCorp. (See BANC Moving to Join CAISO’s EDAM.) BANC members Modesto Irrigation District and the cities of Redding and Roseville have since committed to joining the market.
A commitment from SN would clear the way for BANC to sign an EDAM implementation agreement with CAISO, a well-placed source told RTO Insider.
With WAPA’s approval, BANC expects to join the EDAM in the spring of 2027, the BA said in an Oct. 30 press release.
As part of federal power marketing administration (PMA) WAPA, SN sells low-cost power to irrigation districts, joint power agencies, cities and towns, public utility districts and other public entities from hydroelectric dams operated by the Bureau of Reclamation in the Central Valley Project, including Shasta (676 MW), Trinity (359 MW), New Melones (283 MW) and Folsom (199 MW).
“Working closely with the Balancing Authority of Northern California and our Sierra Nevada customers every step of the way, my staff and I look forward to engaging with CAISO through final negotiations to join this promising day-ahead market development,” WAPA Administrator Tracey LeBeau said in a separate release. “Our dedicated staff will continue to solidify our working partnerships with BANC, customers and CAISO and resolve technical implementation details while ensuring the best possible outcomes for our customers and other stakeholders.”
“We have concluded that participation in EDAM provides the best benefit for BANC and its WEIM participants while leveraging the investment we have made, and preserving the benefits we see, in WEIM,” BANC General Manager Jim Shetler said in a statement. “This decision is also consistent with BANC’s position that evolutionary development of markets in the West provides the most long-term durability. BANC looks forward to collaborating with WAPA-SN and our members as we move forward with EDAM implementation.”
Shetler is a member of the West-Wide Governance Pathways Initiative’s Launch Committee, which for the past year has been developing a proposal to establish an independent “regional organization” (RO) to assume governance of CAISO’s WEIM and EDAM. SN’s membership in EDAM could have at least a minor impact on the governance of the proposed RO, given that the most recent Pathways proposal reserves one seat for PMAs on the RO’s Stakeholder Representatives Committee in either the WEIM or EDAM sectors. (See Revised Pathways Proposal Focuses on Sector Issues.)
In addition to marketing generation from the Central Valley Project Dams, SN also controls portions of the 500-kV Pacific Northwest-Pacific Southwest Intertie, which links the Bonneville Power Administration’s territory in Eastern Oregon with Los Angeles, and the 500-kV California-Oregon Transmission Project linking Southern Oregon with California’s Central Valley. Both lines are vital for moving energy back and forth between the Pacific Northwest and California and the Desert Southwest.
Altogether, the agency operates 884 miles of transmission ranging from 69 to 500 kV and 18 substations.
“Integrating WAPA’s Sierra Nevada region along with BANC into EDAM is a crucial step towards realizing the vision of a fully integrated regional market,” said Elliot Mainzer, president and CEO of CAISO. “Uniting resource-diverse utility partners across the West will enhance reliability, affordability and transmission connectivity. We are thrilled to see our valued partners taking these steps to solidify their position in this market at such a pivotal time.”
