PJM Just Got 220 GW of Applications. The Real Story Isn’t the Number

 

PJM announced that 811 generation projects representing 220,222 MW had landed in Cycle 1 of its reformed interconnection process. The application window closed April 27. The validation phase has begun. Here is the controversial opinion,

The number is going to dominate every grid headline this week. It deserves to. To put 220 GW in perspective, that’s roughly 1.6× the entire installed generation capacity of the United Kingdom, queued up in a single intake window, in a single regional market.

But if you’ve been doing this work for a while, the headline number isn’t the interesting part. The interesting part is what’s inside the number and what PJM’s “first-ready, first-served” framework is now going to do to the projects that thought they were ready.

What’s actually in the queue

The fuel mix tells you almost everything you need to know about where the U.S. grid is right now:

• Natural Gas: 105,797 MW across 157 units. Nearly half of all megawatts queued. Most of it large (think 600+ MW combined-cycle blocks), much of it explicitly siting near load growth corridors.
• Storage: 67,465 MW across 349 units. The largest unit count of any category by far. Storage is no longer an afterthought to renewables; it’s the second-largest fuel category on its own merit.
• Nuclear: 17,906 MW across 27 units. This is the line that should be making people sit up. Nuclear, both large reactors and what is almost certainly a meaningful SMR component, is back in a North American interconnection queue at scale for the first time in a generation.
• Solar: 14,781 MW (142 units) and solar+storage hybrid – 8,890 MW (45 units).
• Wind: 4,726 MW (65 units).
• Hydro: 151 MW.Eleven projects. Not a typo, very interesting.
• Other (biomass, coal, methane, fusion): 506 MW. Fusion in a real queue. Make of that what you will.

Three things jump out.

First, gas won. Whatever the next decade’s policy mix looks like, the developers who applied last week, the ones putting up site control, posting deposits, and committing to a clock, voted with their applications. They expect dispatchable thermal capacity to clear permitting, financing, and turbine supply faster than the alternatives over the planning horizon they care about. That’s not a political statement; it’s a capital allocation statement.

Second, storage is doing something different than it did three years ago. A 67 GW storage queue with 349 distinct units means the average project is around 193 MW. That’s no longer a fleet of 20 MW frequency response batteries bolted onto substations of convenience. That’s grid-scale, multi-hour, deliverability driven storage, and a meaningful share of it is being designed to chase capacity accreditation under PJM’s reformed capacity rules, not energy arbitrage.

Third, the renewables share is smaller than most people will expect. Solar plus solar storage hybrid plus wind comes to roughly 28 GW out of 220 GW. That’s about 13%. For a market that has been talking about a renewables-led queue for the better part of a decade, that’s a structural shift, and it deserves more attention than it’s going to get.

Why “first ready, first served” is an engineering problem, not a paperwork problem

PJM’s queue used to be a waiting room. You filed, you waited your turn, you found out years later whether your project survived the cluster. The reformed process replaces that with something stricter: prove you’re ready before you get studied.

“Ready” sounds like a legal and financial test. Site control documents. Deposits. Milestones. Most of the trade-press coverage of the reform has framed it that way, as a filter against speculative applications.

It isn’t. Or at least, it isn’t only that.

The harder version of “ready” is the engineering version, and it’s the one that decides whether your project clears the validation phase, survives the System Impact Study without a network upgrade cost shock, and lands a Generation Interconnection Agreement on a timeline your financing model can absorb.

We’ve been running interconnection studies inside the PJM footprint for more than 20 years; across the AA-series cycles, the AB cycles, through the transition reforms, and now Cycle 1. A few patterns repeat:

Point of Interconnection screening done after the application is filed. Developers who pick a POI based on land availability and grid map proximity without running power-flow screening, short-circuit headroom checks, voltage stability scans, and a contingency-ranked thermal sensitivity are the ones who get a $300 million network upgrade allocation in the System Impact Study and either eat the cost, withdraw, or appeal. The cluster doesn’t wait for you to figure out that the next 765/500 kV substation over had ten times the headroom.

Plant models that don’t validate. A PSSE or PSCAD model that performs beautifully in factory acceptance testing and then doesn’t replicate field behavior is a familiar story. PJM’s process and the FERC Order 901 environment more broadly is not forgiving on this. EMT model adequacy, benchmarking against PSSE, and validation against actual commissioning test data are now table stakes, not deliverables you negotiate after the fact.

Reactive power and ride-through assumptions copied from a vendor datasheet. Inverter-based resources, especially in dense IBR neighborhoods, behave differently in clusters than they do as standalone units. Reactive capability at the POI under realistic system strength conditions is not the same as the curve in the equipment brochure. We’ve seen good projects get hit with stability findings that were entirely a function of how the model was tuned, not how the plant would actually perform.

Underestimating what a cluster restudy does to your schedule. Withdrawals trigger restudies. Restudies trigger reallocations. A neighboring project pulling out of the queue can turn your $40M upgrade obligation into a $180M one overnight. Defensive engineering, running your own sensitivities on the cluster, not just the base case is what keeps that from being a surprise.

None of this is new. What’s new is that the reformed Cycle 1 process compresses the consequences. Under the old queue, you could discover most of these issues over five to seven years and still have time to react. Under Cycle 1, the study window is one to two years. There is much less room to be wrong.

The hyperscaler factor

We can’t write about this Cycle 1 intake without naming the demand side. PJM expects load to grow by more than 30 GW between 2024 and 2030, mostly from data centers and other large industrial customers. That number is already being revised upward in conversations we’re having.

The data center buildout has changed how generation projects are being underwritten on the supply side. Several of the gas projects in this queue are not merchant in the traditional sense they’re being developed against load. Some of the storage projects are being structured to sit behind the same meter as a hyperscale campus. The line between “generation interconnection” and “large load interconnection” is blurring in PJM in ways that are going to force planning, queue, and tariff policy to keep evolving.

For developers and EPCs, that means the engineering work doesn’t stop at the POI. It now reaches into:

• Coordinated load and generation studies in the same corridor.
• Substation and switchyard configurations that anticipate co-located load.
• Reliability and protection schemes that account for behind-the-meter dynamics.
• Power quality envelopes, harmonics, flicker, transient overvoltage, that match what data center customers will actually accept on their bus.

For hyperscalers and large industrial off-takers, it means the same: an interconnection study is no longer a third-party deliverable they receive at the end of a developer’s process. The technical assumptions baked into that study determine whether the campus can be energized on time, at the capacity contracted, with the reliability the SLA demands.

What we’re watching in the validation phase

PJM has now begun confirming which of the 811 projects submitted what they needed to submit. Some won’t make it through validation. Of the ones that do, the System Impact Studies will start surfacing the projects whose POI selection, models, or readiness evidence was thinner than the application made it look.

A few honest predictions, based on prior cycles and the reform’s design:

1. Withdrawal rates will be lower than the legacy queue’s 74%, but not dramatically lower. The financial commitments raise the bar at entry. They don’t fix bad engineering.
2. Network upgrade cost allocations will be more concentrated. Fewer projects studied, more upgrade weight per project that survives. This is going to surprise developers who didn’t pre-screen.
3. Storage will see the most internal reshuffling. Per-unit MW is still small enough that cluster dynamics will reassign cost responsibility heavily as projects drop.
4. The nuclear submissions are going to demand a different kind of study posture. SMRs in particular don’t behave like the synchronous machines PJM’s models were built around, and the EMT and dynamic studies are going to need careful handling.

The reform is done. The hard part starts now.

The headline number, 220,222 MW, measures ambition. The validation phase, the System Impact Studies, the model benchmarking, the EMT adequacy reviews, the reactive support sizing, the harmonic and transient overvoltage envelopes, the protection coordination, the cluster sensitivities, that’s where the actual capacity gets connected.

We’ve been doing generation interconnection work inside the PJM footprint for more than 20 years; since 2006, when our team ran PJM’s CETL load deliverability test analysis using MUST and PSS/E, several hundred studies. Around 130 GW worth of generation. Wind, solar, gas, storage, hybrid, hydro, and now an increasing share of work supporting hyperscale-driven generation packages and BESS portfolios.

The pattern across thirty years of this work is the same. The projects that get built are the ones whose engineering matched their ambition before the application was filed, not after.

If you’re inside Cycle 1 and reading this, the validation result will tell you one thing about your project. The System Impact Study will tell you the rest. The good news is there’s still time to make sure those two answers agree.

Written from the PowerTek bench. We support generation developers, EPCs, Hyperscalers, BESS Portfolio Owners, and Renewables Sponsors with the engineering studies and grid modeling that decide whether a project clears interconnection on schedule. If your project is in Cycle 1, or you’re already mapping Cycle 2, we’d be glad to talk.