Bonneville Reopens Its Markets+ Decision and Weighs CAISO’s EDAM, Which Runs 39 GW Against 19 GW
- Capacity & Wholesale Markets Policy & Markets Regulatory
Marin Holt
- 0
- 9 minutes read
- Kavulla letter date: September 3, 2026
- EDAM average net generation: 39 GW
- Markets+ average net generation: 19 GW
- Balancing authority interfaces: 18
- PacifiCorp EDAM gross benefits: $5.42 million
Bonneville Power Administration is reopening its decision to join Southwest Power Pool’s Markets+. Administrator Travis Kavulla said so in a September 3, 2026 letter to the Regional Organization for Western Energy. The federal agency is weighing a pivot to the Extended Day-Ahead Market, which the California Independent System Operator runs. A new decision is due before the end of 2026.
Kavulla leaned on federal energy data to make the size argument. EDAM averages 39 GW of net generation and 48 GW of demand. Markets+ averages 19 GW of each. Bonneville’s transmission system serves more than 400 customers and touches 18 other balancing authorities, so the seams between two Western markets land on Bonneville first.
The letter sets out three tests. The first is whether the market’s rules will hold over time. The second is how deep and liquid the market is. The third is how seams between adjoining markets affect reliability and cost. Kavulla also set five governance conditions for the Regional Organization for Western Energy. They are independent board leadership, workforce and location, stakeholder-driven governance, protection against unilateral state action, and a platform for reliable investment. Utility Dive reported that the organization should pass a stakeholder governance framework resolution by November 30, 2026.
How Bonneville Got Here
Bonneville did not arrive at Markets+ quickly. The agency issued a draft policy naming Markets+ in March 2025 and confirmed that direction in May 2025, after a years-long review. Markets+ was built partly around Northwest public power priorities. Bonneville cited governance and the value of the federal hydropower system when it chose. Kavulla, who took the job this year, is reviewing that record rather than defending it.
Northwest Public Power Pushes Back
The Public Power Council published a study and a news release urging Bonneville to hold its course. Its members buy roughly 90 percent of Bonneville’s generation under long-term contracts, so they carry the cost of whichever market wins. Council CEO Scott Simms framed the risk as a closing window. “The status quo isn’t going to sit still while BPA continues evaluating its options,” Simms said. He argued the region should be careful about trading low Northwest power costs for a larger market.
PacifiCorp, which joined EDAM this year, reports gains. Spokesperson Omar Granados said EDAM “has already delivered $5.42 million in gross benefits to PacifiCorp and its customers since its launch.” That figure covers one utility over a few months, and it is gross rather than net. It is a data point, not a settled case.
One thing did change under Bonneville’s feet. California amended its law to allow an independent regional organization to govern EDAM. Governance was Bonneville’s stated reason for picking Markets+ in the first place. If that gap closes, the original decision rests more heavily on market size, and on size EDAM leads.
Why It Matters
Bonneville’s transmission reaches more than 400 customers and 18 neighboring balancing authorities. Whichever day-ahead market it joins becomes that market’s anchor in the Northwest and leaves the other thinner. Utilities and large loads should treat the year-end decision as a fork in their own planning. The market Bonneville picks sets the price signal their long-term contracts settle against. Watch the Regional Organization for Western Energy’s governance resolution this fall. If it lands with real independence, the governance case for Markets+ narrows sharply.
Critical Perspective
The size comparison does less work than it appears to. EDAM is running today with PacifiCorp and others inside it. Markets+ has not reached that stage. Measuring 39 GW against 19 GW sets a market in operation beside one still filling up, and Kavulla conceded that size alone does not guarantee efficiency. The number that decides the question is committed capacity at go-live, and nobody has published that.
The five governance conditions are softer than a checklist looks. Independent board leadership, workforce and location, stakeholder-driven governance, protection against unilateral state action, and a platform for reliable investment are all qualitative. None carries a measurable threshold. The same official who wrote them will judge whether the Regional Organization for Western Energy met them.
Then there is the durability problem, which is Kavulla’s own first test turned back on Bonneville. The agency named Markets+ in a March 2025 draft policy and confirmed it that May. Reopening the question about a year later tells every counterparty that a Bonneville market commitment lasts as long as the administrator who signed it. That is a governance signal, and it favors neither market.
The Public Power Council holds the leverage that matters here. Its members buy roughly 90 percent of Bonneville’s generation under long-term contracts. A pivot to EDAM over their objection buys a rate fight that outlasts the market decision itself. Against that, the $5.42 million PacifiCorp cites is gross, covers months rather than a year, and describes one utility. Nobody should annualize it into a case for Bonneville.
Sources
- Utility Dive: Bonneville eyes switch to CAISO’s EDAM from Southwest Power Pool’s Markets+ (September 8, 2026)
- American Public Power Association: BPA Administrator and CEO Addresses SPP’s Markets+, CAISO’s Extended Day-Ahead Market in Letter (September 8, 2026)
- The Bulletin: BPA to reconsider which electricity market to join (September 4, 2026)
- The Daily Chronicle: Northwest public utilities urge BPA to stay the course on day-ahead market choice
