How to Read a PJM Facilities Study Report

Most developers first encounter a Facilities Study Report the moment they receive one: a PDF that runs anywhere from 40 to 200 pages, filled with tables of transmission facilities, cost columns labeled in ways that are not immediately obvious, and a milestone schedule that looks conditional on everything. This article walks through each major section using project AF1-119 as a concrete example, so you know what you are reading and what to do with the numbers.

What a Facilities Study Is

A Facilities Study is the third and final formal study in PJM's interconnection process. It follows the Feasibility Study and the System Impact Study (SIS). While the SIS tells you whether your project can connect and roughly what upgrades will be needed, the Facilities Study tells you exactly what will be built, who builds it, what it costs, and when it has to be done.

PJM issues a Facilities Study Report after the Transmission Owner (TO) has engineered the specific facilities required to interconnect a project. The report must be accepted and signed before a Generator Interconnection Agreement (GIA) can be executed, which is why it sits at the critical path of any project's development timeline.

PJM posts Facilities Study reports publicly in the Queue Scope section of its website, organized by queue number. You do not need a CEII clearance to access them for most projects, though some network-sensitive detail may be redacted.

Section 1: Project Overview and Cover Terms

The first section of a Facilities Study Report reads like a summary term sheet. For AF1-119, a 200 MW AC solar project interconnecting to the Allegheny substation in western Pennsylvania, this section contains:

• Queue number and project name. AF1-119 is a cluster study designation under the FERC Order 2023 framework, where "AF1" refers to the first Allegheny Power cluster cycle.
• Point of Interconnection (POI). The specific substation bus or transmission line segment where the project taps into the PJM network. Changing this after the Facilities Study requires a material modification request and likely restarts the study clock.
• Requested service type. Whether the project is seeking ERIS (Energy Resource Interconnection Service) or NRIS (Network Resource Interconnection Service). AF1-119 requested NRIS, which means it wants full capacity recognition and must pay for the additional network upgrades that firm deliverability requires.
• Maximum Facility Output (MFO). The nameplate AC output that PJM has studied and will allow the project to inject. For AF1-119 this is 200 MW AC. Any output above the studied MFO is curtailed by the inverter setpoint or a SCADA limit. MFO is often confused with DC nameplate: the Facilities Study is always about the AC interconnection limit.
• Interim Interconnection Service Agreement (IISA). If the project wants to begin generating power before all network upgrades are complete, it may request limited operation under an IISA. The Facilities Study will note whether an IISA is available, at what output level, and which upgrades must still be completed before full-output operation is permitted.

Read this section carefully before anything else. The MFO and service type lock in the commercial scope of the project. If either one differs from what you modeled in your pro forma, you need to understand why before you proceed.

Section 2: Network Upgrade Cost Summary

This is the section most developers turn to first, and it is also the most frequently misread. The cost summary table presents all required transmission upgrades in two columns: Transmission Owner Build cost and Developer Build cost.

The Transmission Owner Build column is what PJM and the TO estimate it will cost for the TO to engineer, procure, and construct each upgrade using its standard contractor relationships and project management overhead. This is almost always higher than the Developer Build column.

The Developer Build column reflects what PJM estimates the developer could negotiate if it were to contract directly with equipment suppliers and construction firms, bypassing the TO's procurement process. Not every facility is eligible for Developer Build; some are restricted to TO Build by FERC or PJM tariff provisions, particularly substation work inside the TO's existing fence.

For AF1-119, the cost summary table looked roughly like this (illustrative values):

The "Developer Facility" row covers work on the developer's side of the point of change of ownership: gen-tie line, collector substation, revenue meter, and SCADA integration. This cost is always the developer's responsibility regardless of build method.

Two things to check in this section that developers often overlook:

• Contingent facilities. Some upgrades are listed as contingent, meaning PJM only requires them if a neighboring project in the same cluster also proceeds. If that neighbor withdraws, the contingent upgrade drops from your cost obligation. These should be modeled as a probability-weighted range in your financial model, not as a fixed cost.
• Allowance for Funds Used During Construction (AFUDC). Long-lead equipment like large power transformers can sit in a queue for 18 to 36 months before delivery. The Facilities Study cost table does not always include AFUDC or carrying cost. Ask your TO contact explicitly whether the numbers are as-engineered costs or include financing overhead.

Section 3: Facility-by-Facility Engineering Detail

After the summary table, the report breaks each facility into its own subsection with a one-line engineering description, the affected voltage level, the Transmission Owner responsible for building or owning it, and (for network upgrades) a cost allocation percentage showing what fraction of the cost is driven by AF1-119 versus other projects in the cluster.

The cost allocation percentage matters because network upgrades shared across multiple cluster members are split proportionally. If AF1-119 is allocated 45 percent of a $6 million substation upgrade, it owes $2.7 million. If the other project that drove the remaining 55 percent withdraws, PJM will run a reallocated cost study. Depending on the timing, this can increase your obligation materially.

This section is also where you will find notes about facility ratings. PJM engineering staff will note the pre- and post-project thermal ratings of affected transmission elements. If a line segment is de-rated after your project interconnects (meaning your power flow causes it to carry less than its current rating under contingency conditions), you may be required to fund a reconductoring project to restore the pre-project rating. These are called "reliability network upgrades" and are non-negotiable; they are assigned regardless of economic benefit to the developer.

Section 4: Milestone Schedule

The milestone schedule is a project timeline expressed as a set of conditions that must be satisfied in sequence before PJM will authorize the next step. It is not a Gantt chart with fixed calendar dates. It is a dependency chain.

For AF1-119, the schedule had the following major milestones (illustrative):

• Execution of the Facilities Study Agreement and payment of the deposit within 30 days of receiving the report.
• Selection of TO Build or Developer Build for each eligible facility within 60 days of GIA execution.
• Procurement of the 138 kV power transformer by the TO, estimated at 22 months from order placement.
• Completion of protection relay upgrades no later than 90 days before energization.
• Developer's collector substation energized and tested prior to interconnection facilities energization.
• Commercial Operation Date (COD) no earlier than the TO's confirmed transformer delivery date plus a 90-day construction window.

The transformer lead time is typically the item that drives the COD. In the current equipment market, 138 kV and 345 kV power transformers are quoting 24 to 36 months from order placement. If the TO has not yet issued a purchase order at the time your Facilities Study Report is delivered, your earliest feasible COD is approximately three years out regardless of how fast you build the solar array.

Ask your TO interconnection coordinator directly: has the transformer been ordered yet? If yes, what is the confirmed delivery date? This single question can save six months of schedule confusion.

Section 5: Dependencies on Other Queue Projects

Every PJM Facilities Study Report for a cluster-studied project includes a section on project dependencies. This is where PJM lists other queue members whose withdrawal or modification would trigger a restudy of your project's network upgrade requirements.

For AF1-119, the dependencies section identified two other projects in the AF1 cluster whose interconnection used the same substation bus. If either of those projects withdrew after GIA execution, PJM reserved the right to re-run the power flow models and issue a revised cost allocation. In practice, restudy events add six to eighteen months to the interconnection timeline and introduce cost uncertainty that can run into the tens of millions of dollars for large projects.

This is the section where the interconnection queue tool becomes directly useful. Before you sign a GIA, you can run a probability-weighted scenario on each dependency project to estimate the likelihood that it proceeds to commercial operation. A project that is deep in the cluster study phase, carries a large MFO, and has been in the queue for more than four years has a materially different withdrawal probability than a project that just entered the queue last cycle.

Where This Fits with Queue Attrition

The Facilities Study sits at the point in the interconnection process where queue attrition data becomes most actionable. Projects that withdraw after the Facilities Study Report is issued but before GIA execution leave behind cost obligations that are reallocated to remaining cluster members. Projects that withdraw after GIA execution trigger restudy events with hard timeline impacts.

Historical PJM attrition data shows that somewhere between 50 and 75 percent of projects that enter the queue never reach commercial operation. But that aggregate figure is not particularly useful when you are trying to model the specific risk from the three other projects sharing your POI. What matters is the individual project-level probability: study phase, technology type, queue age, and whether the developer has posted the deposits and financial security required at each study gate.

The Queue Reality Check tool applies a probability-weighted model to each project at your POI, so you can see not just the raw nameplate MW but the expected MW that will actually interconnect ahead of you. That figure is what drives your curtailment risk, your capacity value, and your revenue under different dispatch scenarios.

Where to Find Facilities Studies

PJM posts Facilities Study reports on its public-facing Queue Scope interface, accessible through pjm.com. Navigate to the Interconnection queue section, search by queue number, and look for the "Facilities Study" document under the project's study history. Most reports are available as PDFs within a few days of issuance.

If you know the queue number of a nearby project that has already received its Facilities Study, reading that report is one of the fastest ways to understand what your own cost exposure might look like at the same substation. The engineering constraints, facility descriptions, and TO Build cost benchmarks for a given substation tend to be similar across projects at the same POI.

For a broader view of which projects at your POI are in or past the Facilities Study phase, use the PJM interconnection queue tool to filter by study phase and see the full competitive picture. The glossary on this site also covers the key terms you will encounter in any Facilities Study report, from cluster study cost allocation to WMPA and surplus interconnection service.