• Solar projects made up the highest percentage of withdrawals, followed by solar + storage, standalone storage, and onshore wind
• High interconnection costs, permitting issues, and loss of ITC tax adders partly to blame for withdrawals; estimated network upgrade costs for DPP 2022 Phase 1 studies in MISO South at over USD 7.2bn

Several MISO developers have spoken with NPM to share their experiences with the MISO queue process that has led to hundreds of application withdrawals in recent months.

As outlined by NPM last week, the MISO DPP 2022 queue cluster alone has seen 63.07 GW of withdrawals across 378 applications. The cluster’s full capacity was 170.8 GW, so the withdrawals account for roughly 32% of the raw capacity, but with just 400 applications remaining in the queue, 49% of total applications have been withdrawn.

According to NPM data, solar makes up the highest percentage of withdrawals with 28.47 GW of capacity followed by solar + storage at 14.54 GW, standalone storage at 11.04 GW, onshore wind at 6.79 GW, hybrid solar + wind + storage at 1 GW and natural gas at 1 GW.

According to developers speaking with NPM, major contributors to the withdrawals include high interconnection costs and permitting issues in addition to some developers losing access to ITC tax adders for energy communities in some areas of MISO due to map changes.

ENGIE’s VP of Business Development Rick Davis called navigating interconnection challenges in MISO “one of the most significant challenges in the development process” and said his firm was “disappointed to withdraw projects from MISO’s grid interconnection process that could otherwise achieve commercial operation within this decade.” NPM data indicates the firm has withdrawn seven projects constituting a complete withdrawal of the projects NPM was tracking from ENGIE in the MISO region.

“On the siting front, we continuously seek locations that balance stakeholder priorities and deliver clean energy to customers facing unprecedented load growth,” Davis said. “However, many of the projects we’ve withdrawn face persistent grid instability along with study-driven upgrade costs and timelines that ultimately make them unviable.”

MISO South constituting Arkansas, Texas, Louisiana and Mississippi appear to be a particularly problematic area in the MISO region with the ISO reporting estimated network upgrade costs for DPP 2022 Phase 1 studies at over USD 7.2bn for MISO South alone. Average upgrade costs in this area reached USD 912,590 in Louisiana, USD 870,891 in Mississippi and USD 761,637 in Texas according to MISO’s July report.

Davis says he would like to see MISO move forward “expeditiously” with its planning for its Long Range Transmission Planning Tranche 3 transmission upgrades for MISO South to help mitigate these concerns. Notably, Tranches 1 and 2 of the LRTP have largely been focused on MISO North, though none of those projects have been completed to date.

The high number of withdrawals from MISO’s 2022 queue cluster is notable as the cluster is the largest in the ISO’s history, marking an exponential increase from previous cycles which saw 52.4 GW in 2020 and 76.8 GW in 2021.

One MISO developer that spoke with NPM anonymously attributed this spike to growing challenges in PJM “creating a lot of pressure on MISO,” even though they say MISO has historically been “considered risky until the end of the interconnection process and required much higher securities that are very difficult to sustain.”

The spike in interconnection requests and withdrawals led MISO to issue policy changes to cut down on the number of projects that could be submitted to future queues, including instituting significantly higher withdrawal penalties for projects as well as higher milestone payments and site requirements. These policies appeared to have some impact on the 2023 cluster which fell from 2022’s 171 GW to 123 GW.

However, MISO was still unsatisfied by the scale and ultimately moved to cancel the 2024 study cluster to give it time to implement a now FERC-approved queue cap for the 2025 cluster.

Study process hurdles

Even with these policy changes, an anonymous developer tells NPM that MISO’s study process remains the core of the issue with “multiple GIAs” issued per project with amendments late in the process leading to “a lot of uncertainty.” While the developer says MISO will typically provide an initial GIA with direct assigned costs, “there’s still a lot of uncertainty on what your network upgrade will be, and it will be amended based on your final.”

“We’re waiting for MISO to give us our final cost and don’t know who’s going to stay based on the latest evaluation and all that, so we have no certainty on that final number,” the developer said.

So far, the 2025 cluster, the first to include a queue cap, has 55 GW submitted under the total 77.82 GW queue cap MISO has instituted. Notably, this cluster has seen a marked increase in gas generation submitted for review. While the 2022 queue was made up of 96% renewables and storage, roughly a third of the 2025 cluster is made up of gas generation. Overall, solar makes up 18.8 GW of the new cluster followed by gas at 17.8 GW, wind at 8.79 GW, storage at 7.23 GW and hybrid renewables and storage at 1.68 GW.

Developers like Arevon have told NPM the new cap is leading to more scrutiny for project siting, potentially cutting down on the number of projects submitted to the queue as MISO intended.

However, EDPR‘s VP of Regulatory and Market Affairs David Mindham told NPM that he expected an increase in the number of projects submitted into the queue in the wake of the queue cap.

“When you make it harder to get through the interconnection process by limiting the number of projects that get through, you’re going to actually expand the number of projects that need to go in in order to get successful projects out,” Mindham said.

An anonymous developer agreed, adding that the cap also sets the stage for larger companies, particularly those investing in gas, to “buy up the whole queue.” Indeed, more than half of the 10.46 GW cap MISO assigned to the East (ITC) region for the 2025 cluster has been filled with gas alone at 5.58 GW.

“We’re trying to be honest and have real projects, but it’s much faster to just show you have the land for gas generation and sweep the whole queue,” the developer said.

Compounding these issues is MISO’s lack of consistency on its study projections. Throughout the summer, the grid operator has delayed study results for multiple cycles, including the 2022 cluster as it seeks to implement new SUGAR automation software that it claims will help speed up the process in the long run.

While no new delays for results for the 2022 cluster were announced in August, just yesterday the ISO announced a fresh set of delays for the 2021 and 2023 cycles ranging from 13 to 49 calendar days depending on the cluster and region, citing issues including delays in stability analysis, cascading delays, short circuits and mitigation refinement delays.

An anonymous developer confirmed to NPM that there is currently “a huge disconnect” between MISO’s communicated study date projections “and reality,” which they say are often 24 to 36 months apart. At times, the developer says these timelines are extended to such a degree that some GIAs submitted to FERC will expire before they can get interconnected.

“Nobody understands why they keep telling you you’re going to get your studies on a certain timeline when they never meet it,” the developer said.