FERC’s June 9, 2026 order accepting PJM Interconnection’s proposed expedited interconnection process, filed under Docket ER26-1563 in the spring, is the second grid-side filter that any bucket-two solar or wind project in the PJM footprint now has to price against. The first filter is the reformed Order 2023 cluster study, which PJM has been running since its transition cluster cleared through Q1 2026 and which controls the interconnection agreement pipeline for standalone solar, wind, storage, and hybrid projects. The second filter is the new expedited window, which is capped at ten interconnection requests per calendar year, is limited to large new or uprated capacity resources, and sunsets on December 31, 2027. The two processes do not compete for the same applicant pool. They compete for the same network capacity, and the sequencing puts the expedited window first.
The expedited window is not a solar and wind pathway. The eligibility criteria in the accepted tariff filing restrict the process to interconnection requests for new or uprated capacity resources that meet PJM’s capacity performance definitions and that clear a size threshold at the large capacity level. In practice the eligible pool is natural gas combined-cycle, natural gas combustion turbine, coal life extension via nameplate uprate, and nuclear uprate. The 2028 to 2029 base residual auction pricing environment, with the price collar that PJM filed in February 2026 and FERC accepted on consumer cost grounds, and the run of the reference combined-cycle cost of new entry toward the pre-collar cap, is what put dispatchable capacity at the front of the queue.
What the expedited process actually approves
The tariff mechanism approved in June has three moving parts.
First, an application window that runs continuously rather than aligning with the cluster study cycle. Interconnection customers file at any time, PJM conducts a preliminary system review on an accelerated timeline, and the request is either advanced to the expedited study or declined on eligibility or system impact grounds. The published timeline in the tariff is a preliminary review within roughly 60 days of application acceptance and a full expedited system impact study within roughly six months of that review, against the twelve to eighteen month cadence of the standard cluster study cycle.
Second, a cap of ten interconnection requests approved through the expedited window in any single calendar year. The cap is a hard number on approvals, not on applications. PJM can accept more than ten applications and can advance more than ten through preliminary review. What the cap constrains is the number of expedited interconnection agreements that PJM can execute in a calendar year. The queue-management effect of the cap is that applicants have an incentive to file early in the calendar year rather than late, and applicants that miss a given year’s cap sit in the queue for the following year rather than being pushed back to the standard cluster cycle.
Third, a sunset date of December 31, 2027. The expedited process is authorized as a bridge measure through the 2027 to 2029 reliability window that the four-lever capacity stack is being built to address. After the sunset, all new capacity resource interconnection requests return to the standard cluster study cycle. FERC’s acceptance letter framed the sunset as a condition of approval, not as an aspiration.
The three parts together define the tariff-authorized ceiling. Twenty expedited approvals through the sunset, spread across the 2026 and 2027 calendar years, is the outside case. The realistic case is fewer than twenty, because the preliminary review is expected to decline some applications on system impact grounds and because the year-two application volume depends on whether the year-one clearing rate suggests the process will actually deliver a capacity resource by 2028 or 2029.
The relevance to bucket-two solar and wind
The OBBBA bucket-two pipeline, the projects that began construction between January 1, 2026 and July 4, 2026 and have a placed-in-service deadline of December 31, 2030 under the four-year continuity safe harbor, is running on the standard cluster study cycle. It is not eligible for the expedited window. The relevance of the expedited window to bucket-two solar and wind is not that it accelerates the same projects. The relevance is second-order, on two channels.
The first channel is network upgrade cost allocation. The expedited process is authorized to trigger network upgrades on the same interconnection cost allocation methodology that the standard cluster study uses. When an expedited request approves a new gas combined-cycle at a substation that also serves as an injection point for queued solar and wind projects in the same cluster, the network upgrade cost that the expedited project triggers may lower the marginal upgrade cost that the cluster projects would otherwise face, or may raise it, depending on the specific power flow contribution and the allocation formula. The direction of the effect is location-specific and cluster-specific, and it is not predictable in the aggregate. What is predictable is that bucket-two cluster projects will see a network upgrade cost line item at the interconnection agreement stage that has been recalculated to reflect the expedited approvals ahead of them, and that recalculation will not always be in the cluster’s favor.
The second channel is study queue capacity. PJM’s transmission planning group runs both the cluster study cycle and the expedited studies. The expedited system impact studies are added on top of the standard cluster workload, and the tariff commits PJM to the expedited timelines as a matter of study-team resource allocation. The realistic effect on the cluster cycle timeline is that the second post-transition cluster, which is scheduled to close its application window in late 2026 and to post study results across 2027 and early 2028, may see marginal slippage on the study completion milestones. Any slippage tightens the bucket-two placed-in-service window at the back end, because a project cannot execute an interconnection agreement, sign an EPC contract, and complete construction inside the four-year continuity safe harbor if the interconnection agreement itself slips into 2028 or later.
Neither channel is a first-order impairment of the bucket-two pipeline. Both channels reprice the bucket-two projects at the margin, and the direction is generally toward higher network upgrade cost and later interconnection agreement dates rather than lower and earlier.
What the expedited approvals will actually look like
The near-term expected use of the expedited window is a narrow set of gas combined-cycle projects that were already in the standard PJM cluster and that had a credible path to a 2028 to 2029 commercial operation date, plus a smaller set of coal life extension nameplate uprates that fall inside the four-lever framing for the 2027 to 2029 reliability window. The expedited window pulls those projects out of the standard cluster and into the fast lane, which frees a small amount of study queue capacity for the remaining cluster members but which also frees the pulled projects from the cluster’s cost allocation formula and reassigns them to a project-specific network upgrade cost.
A single new nuclear uprate application through the expedited window, if PJM’s transmission group can complete the system impact study inside the tariff timeline and if the applicant can complete the physical uprate work by the sunset, is worth several hundred megawatts of firm capacity. That is the most valuable single expedited approval PJM could deliver in the two-year window, and it is not a certainty.
The realistic expected count of expedited approvals through the sunset is a single-digit number in each of 2026 and 2027, delivering a two-year aggregate of expedited capacity in the low single-digit gigawatts. The 2028 to 2029 base residual auction is the auction where the effect on cleared capacity will be visible. The 2029 to 2030 auction is where the effect on clearing prices will be visible, on the assumption that the price collar remains in place through that auction cycle.
The read for bucket-two developers
The action item for bucket-two solar and wind developers in the PJM footprint is to model the interconnection agreement date as a distribution rather than a point estimate, with the mean shifted later by roughly one to two study milestones relative to the pre-expedited-process case, and with the network upgrade cost line item modeled as a range rather than a fixed number. The four-year continuity safe harbor gives bucket-two projects until December 31, 2030 to reach placed-in-service. A project whose interconnection agreement slips from Q3 2027 to Q2 2028 inside the range still clears the placed-in-service deadline. A project whose interconnection agreement slips into 2029 is at the edge of the buildable window and needs to be rerun on the tax-equity and offtake terms that assume a compressed construction schedule.
The expedited window is a small process in absolute terms. Its effect on the bucket-two pipeline is proportional to its size, which is to say small on average and concentrated at specific substations where dispatchable and clean capacity interconnection requests overlap. Bucket-two developers should read the expedited approvals as they post, note the substations involved, and reprice the affected cluster positions accordingly.