NV Energy’s decision to join CAISO’s Extended Day-Ahead Market (EDAM) rather than SPP’s Markets+ was based partly on concerns that participation in the latter would “lead to substantial expenditures with limited results,” a representative of the Nevada utility said.

In contrast, NV Energy has “high confidence” that EDAM’s first-movers will stand up the market and it will have the connectivity to produce customer benefits, according to David Rubin, the utility’s federal energy policy director.

Rubin was speaking Oct. 28 at a meeting of Nevada’s Regional Transmission Coordination Task Force to give an update on the utility’s day-ahead market activities.

The RTCTF was created by 2021’s Senate Bill 448, which also requires transmission providers in the state to join an RTO by Jan. 1, 2030.

In May, NV Energy confirmed in public statements and regulatory filings that it intends to ask the Public Utilities Commission of Nevada (PUCN) for authorization to join EDAM. (See NV Energy Confirms Intent to Join CAISO’s EDAM.)

The decision is viewed as an important victory for EDAM because of NV Energy’s central location in CAISO’s Western Energy Imbalance Market (WEIM).

Rubin showed a diagram with dark blue circles depicting balancing areas expected to participate in EDAM, including PacifiCorp, Portland General Electric, the Los Angeles Department of Water and Power, Idaho Power and the Balancing Authority of Northern California.

Expanding that footprint to include other WEIM entities would provide even greater benefits to participants, Rubin said. But even if the footprint doesn’t widen from what’s now expected, “the dark blue footprint with its connectivity should produce extensive benefits,” he said.

A Brattle Group study for NV Energy showed that footprint contains 46% of WECC’s load, 80% of the solar generation, 70% of the storage capacity and much of the wind power, Rubin said.

It projected that the utility’s annual benefits with EDAM would range from $62 million to $149 million, depending on the market footprint. In contrast, results from Markets+ participation would range from a $17 million annual loss to a $16 million gain. (See NV Energy to Reap More from EDAM than Markets+, Report Shows.)

Stakeholder Role

Another factor NV Energy weighed in its day-ahead market decision was the role of stakeholder participation.

In EDAM, CAISO staff work to balance positions expressed by stakeholders, Rubin said, while Markets+ employs a stakeholder-led process in which staff are more passive.

Rubin said that when NV Energy participated in the SPP process, Northwest entities tended to vote as a block while Southwest entities often varied in their opinions. As a result, NV Energy was frequently outvoted, he said.

In CAISO’s process for EDAM, “staff involvement helps protect minority interests that can get overruled by SPP’s deterministic voting structure,” Rubin said.

CAISO’s process also makes greater use of written comments, he said, which allow stakeholders to more fully explain their positions. And the written comments can be reviewed by those who weren’t able to attend a meeting.

Building on WEIM Benefits

By joining EDAM, NV Energy can build on the substantial benefits it has earned through participating in WEIM since December 2015.

CAISO announced Oct. 28 that overall WEIM benefits have grown to $6.25 billion; NV Energy has seen cumulative benefits of $589 million through the third quarter of 2024.

Rubin said NV Energy’s WEIM benefits have grown appreciably as the company has gained experience in the market and its footprint has expanded. Those benefits have helped bolster NV Energy’s confidence in EDAM.

In contrast, “we have less confidence in Markets+, even if entities spend the $150 million necessary to build out the SPP design,” he said.

NV Energy expects to file a request for authorization to join EDAM with the PUCN in the second quarter of 2025. That timing will give the company time to complete its integrated resource plan filed with the commission and see how the footprints evolve for the two competing day-ahead markets.

There also may be reactions by then to PacifiCorp’s open access transmission tariff for its participation in EDAM, expected to be filed with FERC in November, as well as a potential PGE filing in January.