After nine years, MISO will close out its multiphase market platform replacement project, leaving a bulk of unfinished work on its real-time market.

MISO said it’s “adjusting the remaining scope to conclude the program in 2026,” and will cut its work to build a new unit dispatch system from the multiyear effort. That undertaking will become a standalone project.

MISO’s unit dispatch system balances generation and load in five-minute intervals to clear the real-time market, selecting generators’ offered megawatts and prices while managing transmission congestion and meeting reserve requirements. The system sends five-minute dispatch and price signals to generators based on bids and system need.

MISO’s removal of a new unit dispatch system from the market platform project means that the RTO will spend an estimated $154 million on the market platform swap-out, not including the unit dispatch system. MISO began the platform project with a $130 million budget plus a 25% contingency, bringing the total spending limit to $162.5 million.

MISO said even though it’s cutting out the capstone task of the platform replacement project, the work thus far on the project would deliver about $425 million in benefits.

“Obviously, we’ve spent more than we anticipated,” MISO’s Scott Daugherty said during a Jan. 15 meeting of the Market Subcommittee. Daugherty added the expense is part of MISO being on the “cutting edge” of incorporating the newest technologies.

The RTO said it was experiencing difficulties completing work on the real-time market clearing engine in late 2025. At the time, it predicted that building a new unit dispatch system would cost about $20 million and take until 2028. (See MISO: Market Platform Replacement will be Overbudget, Stretch into 2028.)

MISO planned to build the unit dispatch system over 2026, test and deliver it sometime in 2027 and formally launch it in 2028. It’s unclear what a new budget and timeline might be. In the meantime, MISO will make do with its existing system.

MISO principal adviser Kevin Larson said re-platforming MISO’s market has been a complex endeavor.

“We originally hoped to be done with this in the late 2024/2025 timeline,” Larson said. (See MISO Sets Sights on 2025 Completion for New Market Platform.)

Daugherty said isolating the unit dispatch system overhaul as its own project will allow MISO to work more automation into the finished product.

“Eventually we’ll get the UDS to the current re-platformed engines,” he said.

“The core objective we were going after is performance and security,” Larson added.

In response to stakeholders’ questions, Larson said the new market platform won’t be embedded with AI-based technology. Larson said AI would show up in the market’s “secondary capabilities,” like MISO’s uncertainty management tool, which helps guide dispatch.

Some stakeholders said they were disappointed with MISO’s decision to strike the dispatch system rebuild.

“I’m trying to be calm; I am frustrated with this, but I understand this is difficult to do,” Fresh Energy’s Mike Schowalter said.

Schowalter said MISO has told stakeholders repeatedly the market platform replacement would allow MISO to make more complex market changes. He asked to what extent “carving out” the unit dispatch system would impede what’s possible.

Schowalter said the new market platform always has seemed like “black box that’s going to do all these magic things” that stakeholders might not understand. He asked for a more detailed explanation of what new capabilities the market platform would enable.

“What are those things that are going to have to wait another two years?” Schowalter asked. He added there’s “a lack of understanding on what’s waiting for what.”

Daugherty said the purpose of the market platform replacement is to “not do much that’s new but re-platform the existing capabilities” and position the markets to be more adaptable to new technologies and increasingly complex market products.

“We’ve had this big chunk of market enhancements we haven’t been able to go after,” Daugherty said.

Clean Grid Alliance’s David Sapper asked where MISO’s work to bring aggregated distributed energy resources into the market under FERC Order 2222 stood.

MISO staff took down the question to address later.

Michigan Public Power Agency’s Tom Weeks said the market platform replacement was sold by MISO as: “OK, all the things we can’t do in terms of improving the markets, we can do” once the new platform is in place. Weeks made the comment while asking MISO to create a commitment process especially for jointly owned generation resources.

MISO said the remaining sections of in-progress market platform work are positioned to be completed at the end of 2026. That includes the launch of its reliability assessment and commitment market tool, its look-ahead commitment tool and its one-stop repository for planning and operations data to create its models.

MISO unveiled its new day-ahead market clearing engine as part of the project in 2024.

Larson said MISO began the platform project in 2017 when it began having “on and off problems” with its day-ahead market clearing engine. At that time, it had a wish list of improvements the aging market platform wouldn’t be able to handle.

MISO needs pieces of the market platform replacement, specifically the new look-ahead commitment tool, to be able to comply with FERC’s Order 881, which requires real-time ambient-adjusted line ratings.

The look-ahead commitment tool works with the unit dispatch system to arrange near-term generator commitments.

Order 881 by 2028

MISO said it doesn’t expect full compliance with Order 881 until the end of 2028, due in part to the delay of the new look-ahead commitment clearing engine. (See MISO to Seek 3-Year Order 881 Delay for Vendor Holdups.)

At a Jan. 13 Reliability Subcommittee meeting, MISO also said its vendor might not be able to deliver the necessary software as scheduled in the second half of 2026 to ready its real-time system to incorporate the varied ratings. MISO added that its transmission owners are expected to prepare for the new rule into 2027.

“MISO’s systems being ready doesn’t mean that TO systems are ready,” MISO’s Paul Kasper said. He reminded stakeholders that TOs must conduct their own system testing and integration campaigns.

Kasper said MISO is taking “exceptional” steps to maintain its timeline on the project. “There’s only so much we can control with the vendor.”