DETROIT — MISO’s generator interconnection queue has fallen to 215 GW as developers cut back on projects in response to the federal phaseout of renewable energy tax incentives, RTO leadership said Sept. 16 during Board Week.

The queue currently contains 1,127 projects at 215 GW. That’s down from more than 300 GW earlier in 2025.

“We’re starting to see significant withdrawals,” MISO Vice President of System Planning Aubrey Johnson told the System Planning Committee of the Board of Directors.

Johnson said projects that entered the queue in 2023 would be hard-pressed to be online in time to meet a 2028 phaseout of federal tax incentives. He said developers are making decisions to trim projects based on the changing economics.

MISO’s tariff expects that generation projects can scale the regular interconnection queue within 373 days; however, the actual average timeline is 1,511 days. The RTO is working to get to a 365-day completion rate with the help of automated studies from tech startup company Pearl Street Technologies. (See MISO: New Software Effective, Faster than Previous Queue Study Process.)

Johnson said resource changes are showing up in the next set of members’ integrated resource plans. Currently, MISO’s 2023 cycle is down to 102 GW from the 123 GW of projects that entered.

“We expect to see significantly more withdrawals in the 2023 cycle,” Johnson said.

Meanwhile, 75 GW are all that remains of MISO’s jumbo, 171-GW 2022 cycle, and 38 GW still are standing from MISO’s 77-GW 2021 cycle.

MISO said it processed 100 generator interconnection agreements totaling 17 GW from November 2024 to August 2025. Historically, only about 20% of generation proposals ever make it to interconnection agreements. The RTO expects to add 10.9 GW in nameplate capacity (6.2 GW on an accredited basis) over the rest of 2025.

Johnson said the clampdown on MISO’s penalty-free withdrawals for projects in the queue also could play a supporting role in the project drop-offs.

Executive Director of Transmission Planning Laura Rauch said that although MISO members are tweaking the near-term resource plans they previously communicated, their emissions targets and renewable energy goals remain unchanged in the long term. She said there’s an “acceptance that it will take longer to get to the endpoint, but no changes in those endpoints as of yet.”

Finally, Johnson said the first 10 generation projects MISO selected for its first interconnection queue fast lane all seem viable, and MISO would begin official studies within days. Half of the first class admitted into MISO’s interconnection queue fast lane are natural gas units and account for 4.3 of the 5.3-GW lot. (See MISO Selects 10 Gen Proposals at 5.3 GW in 1st Expedited Queue Class.)

“We showed only one constraint, and the network upgrades look like they’re going to be in the couple hundred-thousand-dollar range,” Johnson said of transmission needed to accommodate the new generation. He credited MISO’s previous long-range transmission planning for making expedited generator interconnections possible.