EDAM and SPP’s Markets+ will reshape the WECC market landscape, dividing it into four distinct markets: CAISO, EDAM, SPP, and Markets+. This structure will create new market seams, and the relative position of Balancing Authorities and Transmission Service Providers to these seams will significantly disrupt existing bilateral trading frameworks.

Understanding the scheduling mechanisms of EDAM and Markets+ is essential for participants in WECC. While these frameworks introduce added complexity, they are critical for calculating day-ahead schedules and revenues across market seams.

Within EDAM, the modeling and scheduling of power imports and exports between Balancing Authority Areas (BAAs) are managed through Transfer System Resources (TSRs). These mechanisms are designed to optimize transfers and fall into four categories based on how capacity is released:

Type 1: Energy transactions handled bilaterally between transmission customers

Type 2: Capacity released by transmission customers for EDAM optimization

Type 3: Capacity eligible for Resource Sufficiency Evaluation (RSE) released by EDAM entities

Type 4: Capacity released by EDAM entities that is not RSE-eligible

The biggest impact to PPA generators is that EDAM is no longer supporting base schedules. Self-scheduling and exercising existing transmission rights can achieve a similar result to base scheduling, but the resources will be settled directly through the market.

All resources within an EDAM BAA must participate in both the DA and RT markets by submitting economic bids or self-schedules. Resources will receive DAM schedules, and so won't need to submit base schedules to the RT WEIM. Additionally, all EDAM participants will either need to be their own scheduling coordinator (SC) or must be represented by an EDAM SC.

No, EDAM is not expected to “dry up” bilateral trading, though some gradual decline may occur as incentives to self-schedule decrease with a larger footprint and growing market confidence.

EDAM is designed to complement bilaterals, with mechanisms that preserve third-party transmission rights and align with open access transmission tariffs. Type 1 transfer system resources (TSRs) support bilateral transactions, allowing transmission customers to self-schedule using their physical and financial rights. While higher-priority schedules may displace physical flows, Type 1 TSRs retain financial rights and remain RSE-eligible.

EDAM also supports inter-scheduling coordinator trades outside the CAISO BAA to facilitate bilateral settlement. Additionally, a transition period will allow contracted RA and RPS imports to be bid at internal EDAM interties (e.g., CAISO–PacifiCorp) to support market launch.

All transactions in CAISO and EDAM—except CRRs—must be conducted through a registered scheduling coordinator (SC), as CAISO settles financially only with SCs. Utilities and IPPs outside EDAM or WEIM must either register as an SC or work with one to submit bids or self-schedules at external interties. The SC assumes full financial responsibility for all schedules, dispatch instructions, and ancillary service awards.

Yes, IPPs in the Desert Southwest can participate in EDAM, but the structure depends on whether the BAA the IPP belongs to is located inside or outside of the EDAM or WEIM market footprint. IPP resources within an EDAM BAA participate similarly to resources in CAISO today. Resources outside the EDAM footprint can still self-schedule or submit economic bids, though requirements vary by intertie type (internal vs. external), host-BAA's market participation, and whether the resource is location-specific. EDAM does not allow base scheduling—resources must actively participate and be registered for both EDAM and WEIM, as day-ahead schedules create real-time obligations. In all cases, resources must secure transmission to the EDAM boundary and will be subject to EDAM transmission access charges.

We expect these changes to begin with the market go-live on May 1, 2026.

We expect these changes to begin with the market go-live on May 1, 2026.

EDAM is not a one-time implementation, and teams should plan for ongoing change, especially in the early phases. 

While the market will eventually mature, it won't stabilize immediately after go-live. CAISO will continue refining the market through updates, corrections, and enhancements as participants begin operating. Over time, EDAM will stabilize. But in the near term, success will depend less on how well you implement the market and more on how effectively you can adapt to continuous change. 

You can find out more information by going to the Yes Energy help system (Yes Energy login required). You can also reach out to your dedicated account manager or support@yesenergy.com.

We expect these changes to begin with the market go-live on May 1, 2026.

EDAM is not a one-time implementation, and teams should plan for ongoing change, especially in the early phases. 

While the market will eventually mature, it won't stabilize immediately after go-live. CAISO will continue refining the market through updates, corrections, and enhancements as participants begin operating. Over time, EDAM will stabilize. But in the near term, success will depend less on how well you implement the market and more on how effectively you can adapt to continuous change. 

You can find out more information by going to the Yes Energy help system (Yes Energy login required). You can also reach out to your dedicated account manager or support@yesenergy.com.