MISO on Monday assured stakeholders that it has the means to study the 170 GW of new generation requests that were added to its interconnection queue in September.

However, stakeholders seemed unsure whether the grid operator is up to the task, bolstered, perhaps, by Berkeley Lab’s analysis showing it’s more expensive than ever for generation to connect to the footprint’s grid.

MISO said last month it must sort through a record 171 GW of proposed generation projects across 956 interconnect requests for the 2022 cycle. The requests could bring the queue to the brink of 300 GW, triple what was there just two years ago. (See MISO: Record 1,000 Interconnection Requests in 2022.)

Phil Van Schaack, manager of resource utilization, said the 2022 cycle almost doubled the requests received in 2021.

“MISO saw nearly 100% growth year over year,” Schaack said during Mondays’ Interconnection Process Working Group (IPWG) teleconference. He said the megawatt value of this year’s queue entrants is “greater than all the installed capacity in the MISO commercial model.”

Five years ago, the RTO’s planners said processing what was then a 60 GW queue was a tough proposition. (See MISO Works to Address Unprecedented Queue Volume.)

Van Schaack said solar generation is dominating the queue and a record number of requests came from first-time developers in MISO. If all the interconnection requests are realized, the queue would be composed of more than 95% renewable and storage resources.

“Not all of these projects will make it to the end, but still, record setting-numbers,” he said. “We appreciate everyone working with us as we work through these requests.”

Staff is reviewing the projects to validate whether they have secured site control, Van Shaack said.

Invenergy’s Arash Ghodsian asked whether there’s a plan to handle the technical challenges in studying the huge volume of requests. “Will MISO be able to solve the models with the magnitude of generation in the queue?” he asked.

WEC Energy Group’s Chris Plante suggested the RTO might need to change its study strategies, given the generation additions.

Van Shaack said staff is prepared to solve models with the best available information and bring on additional people to help, if necessary.

“We’re going to do our best to meet the timeline,” he said. “The need to scale and augment the internal process is ongoing … We do anticipate being able to handle this.”

NextEra Energy’s Aaron Bloom asked whether MISO plans to revisit its three 20-year futures used for transmission planning in light of the generation plans. Staff responded they will internally discuss refreshing the futures’ assumptions.

Stakeholders also requested MISO lead workshops for updates on the queue.

Stakeholders Ask About Odds of IC Agreements

As MISO normally sees about 80% of interconnection requests withdrawn from the queue, stakeholders asked whether staff expects a similar result with the 2022 round.

“We don’t know what the dropout rate is going to be. Historically, the number has been a 20% success rate. But two big things happened that drove the numbers we saw,” Andy Witmeier, director of resource utilization said, pointing to the Inflation Reduction Act’s renewable energy tax credits and the 18 new 345-kV lines from MISO’s long-range transmission plan (LRTP).

The grid operator’s board of directors approved a $10 billion LRTP portfolio of projects in MISO Midwest this summer, partly to integrate more renewable energy. It also intends to stand up $1 billion in projects on its western seam through its Joint Targeted Interconnection Queue study with SPP.

“Those could affect the dropout … But this is still a historic amount of generation,” Witmeier said. “You could see a lot of upgrades coming out of these. First off, there’s just not enough people to buy this capacity.”

Van Schaack said staff could still find prohibitively expensive network upgrade assignments among the latest generation hopefuls.

“That economic trend has definitely continued into 2022,” he said, referencing projects from earlier queue cycles that were unviable because they were paired with pricey upgrades.

Berkeley Lab Focuses on Snowballing Upgrade Costs

Lawrence Berkeley National Laboratory observed last week that MISO’s interconnection environment has led to “rapidly growing” interconnection costs over the past four years.

The national laboratory said in an Oct. 7 study that RTO’s average network upgrade cost of $102/kW for recently completed projects is nearly double that of historical costs from 2000 through 2018. The lab also said that projects still actively moving through the queue faced estimated interconnection costs that have tripled in just four years to about $156/kW.

The cost analysis was funded in part through the U.S. Department of Energy’s Interconnection Innovation e-Xchange.

“The capacity associated with [new] requests is more than twice as large as MISO’s peak load in recent years — about 120 GW — and, if substantial amounts are built, will likely exert competitive pressure on existing generation,” Berkeley said. “However, most projects have historically withdrawn their applications, often in response to high interconnection costs: only 24% of all projects requesting interconnection between 2000 and 2016 have ultimately achieved commercial operation at the end of 2021.”

The lab said 366 GW of projects have left the queue, while just 62 GW have been interconnected. It said the most recently withdrawn interconnection requests confronted the highest average upgrade costs of about $452/kW.

Berkeley also said that the potential interconnection costs on recent submittals for storage, wind and solar generation are more expensive than for natural gas-fired generation. It found that wind generation has $399/kW in network upgrade costs, storage $248/kW and solar $209/kW; natural gas is expected to pay a more modest $108/kW.

MISO Adamant on Narrower DFAX Cutoff 

MISO still plans to reduce congestion by instituting a lower system-impact threshold on interconnecting generation that will likely prompt more network upgrades.

The RTO’s proposal might dim the prospects for some of the new interconnection requests.

The RTO suggested this summer to halve new generation’s allotted distribution factor (DFAX) impact on transmission from 20% to 10% for its basic and unguaranteed level of interconnection service, called energy resource interconnection service (ERIS). (See MISO Recommends Lower Distribution Factor to Address Congestion.)

At the behest of some MISO South members, the grid operator studied a DFAX limit down to 5% but decided that the threshold would be too drastic. Staff said 10% provides a good balance without being too aggressive.

Generation developers maintain that a tighter DFAX threshold would be punitive and place even more responsibility for system planning on interconnection customers, who are trying to get sorely needed generation on the system.

Sustainable FERC Project’s Lauren Azar said during the IPWG’s Monday meeting that lowering the threshold will “exacerbate and result in more transfer of costs to generators.”

Some stakeholders argued that MISO was conflating transmission reliability with real-time congestion costs.

“Interconnection is about reliability and not addressing congestion. What’s resulting is congestion in real-time, which is an economic issue. ERIS generators are energy-only and should expect to be curtailed,” Clean Grid Alliance’s Natalie McIntire argued.

Staff contended that the binding constraints interconnections cause are a reliability issue. They said potential constraints are currently being ignored in the interconnection process, only to crop up later on the system.

Stakeholders said that it’s premature to lower the DFAX threshold across the board when MISO hasn’t yet put together an LRTP portfolio for its southern region. The current and upcoming LRTP portfolios are marketed as being able to support more generation interconnections on the grid.