A Tale of Two Seams Perspectives
CAISO CEO Elliot Mainzer released a new blog this week, sharing eight principles for managing seams as multiple day-ahead markets develop across the West. Mainzer reiterated the success of the WEIM, citing that the WEIM covers 80% of Western electricity demand and has delivered billions in savings across 22 entities and 11 states, and hopes that all current WEIM participants carefully consider the impacts of a split market with seams. He also offered that deeper integration, not fragmentation, is the best path forward.
SPP also held a one-day "Western Seams Symposium" yesterday and updated their resources page, showcasing their own perspective on seams in the West and how they should be managed. Similar to CAISO, SPP, and other symposium panelists agreed that reliability should remain the most important principle in thinking about managing seams. However, much of the symposium also focused on downplaying the risks of seams and market fragmentation in the West and playing up SPP's experience in managing seams in the East. CAISO and EDAM participants were largely absent from the conversation, although SPP VP of Markets Carrie Simpson closed the symposium by noting that they hope and plan to co-host future seams conversations alongside CAISO.
ROWE Formation Board Appoints Interim Leadership, Work Continues to Move Ahead
The ROWE has appointed Kathleen Staks as interim president and Lisa Tormoen Hickey as interim president, making another step forward in the organization's launch. Next steps include the interim Formation Board moving forward with implementation tasks such as securing startup funding and seating the ROWE's initial independent board. The Tariff Work Group and Office of Public Participation Work Group are hard at work, and while the Stakeholder Process Work Group has not started convening again yet, the Formation Committee is working with the Regional Issues Forum (RIF) and the CAISO to develop plans for implementation of the ROWE's stakeholder process.
The Launch Committee is accepting stakeholder donations and grant contributions to pay for the ROWE's start-up costs. Additionally, CAISO has proposed backing up the ROWE with a startup $8.5 million loan that would begin mid-2026, with costs to be recovered through small fees on WEIM and EDAM market participants. The funding will cover the ROWE's initial operations, including staffing, contracts, and other startup costs, and will replace the organization's current reliance on donations, grants, and volunteer hours.
The next Pathways stakeholder meeting is March 27, and you can find the meeting information on the WIEB website here.
WEIM Surpasses $8 Billion in Economic Benefits
The Western Energy Imbalance Market (WEIM) has surpassed $8 billion in cumulative economic benefits since its launch in 2014, generating $1.62 Billion in economic benefits to participants during 2025, and has delivered $415 million in Q4 2025 alone. NV Energy, PacifiCorp, and LADWP were among the top beneficiaries. Participation in EDAM is expected to deliver even greater cost savings and reliability benefits across the West.
CAISO also announced this month that Black Hills Energy, based in Rapid City, South Dakota, and PowerWatch, in Great Falls, Montana, are set to join the WEIM in May.
