Illinois is weighing whether energy-only interconnection rules still fit the state’s reliability and cost needs as of November 5, 2026. The central policy question is not whether faster interconnection is desirable; it is whether the state can improve project entry without shifting poorly defined upgrade costs to customers or weakening resource adequacy in zones facing retirements and load growth.
The issue sits between two measurable pressures. First, interconnection queues include far more proposed capacity than has historically reached commercial operation, which makes queue size a weak proxy for dependable supply. Second, reliability data show that Illinois, especially the ComEd service area, has achieved notable distribution reliability gains, but distribution outage performance is not the same as having enough deliverable generation during peak system stress.
Why energy-only interconnection Is Under Review
energy-only interconnection And Queue Attrition
An energy-only interconnection framework generally allows a generator to connect without receiving firm deliverability rights for capacity purposes. That can lower initial barriers for some projects, especially renewable and storage resources that may not need capacity accreditation at the outset. The policy trade-off is that an easier entry path can leave system planners with a long list of speculative or only partly developed projects.
Illinois queue data in the research record indicate substantial scale, with hundreds of active requests and many gigawatts of proposed generation and storage capacity awaiting action through MISO and PJM transmission providers. The same record also indicates high withdrawal rates for historical requests. Those two facts should be read together: a large queue may show developer interest, but it does not establish that resources will be built, financed, tested, and available when system operators need them.
This distinction matters for policy design. If reforms focus only on speed, they may reduce administrative delay while leaving intact the risk that projects enter the queue before land, financing, equipment, or network impacts are well understood. If reforms focus only on stricter entry standards, they may screen out weaker projects but raise early costs for projects that could otherwise help replace retiring resources. A balanced approach needs evidence on both project readiness and system impact.
What Reliability Data Can And Cannot Show
ComEd’s 2023 reliability report states that its overall SAIDI for 2023 was 85 minutes, a 71% improvement compared with its 2007-2011 average, while SAIFI was 0.53, a 61% improvement over the same baseline ComEd reliability report. Those figures support a cautious finding: distribution reliability in the ComEd area improved substantially over that baseline period.
They do not, by themselves, prove that the generation mix will remain adequate under all retirement and demand scenarios. SAIDI and SAIFI measure customer interruption duration and frequency, often influenced by storms, equipment condition, vegetation management, and distribution automation. Resource adequacy instead asks whether enough supply is available and deliverable during high-risk hours. Reform should not treat strong distribution metrics as a substitute for capacity and deliverability analysis.
Cost Allocation And Reform Options
First-Ready Queue Rules
Federal policy has already moved toward queue discipline. FERC Order No. 2023, effective November 6, 2023, required transmission providers to shift from serial first-come processing toward first-ready cluster study procedures, with requirements such as financial readiness, site control, withdrawal penalties, and cost allocation based on proportional impacts, as described in Lawrence Berkeley National Laboratory’s review of generator interconnection policy LBNL interconnection review.
For Illinois, that federal shift is relevant but not sufficient. Transmission interconnection reforms can improve study timing, but state policy still affects distribution-level rules, cost assignment, transparency, and the treatment of projects that do not seek full deliverability. An effective state response would align readiness screens with Illinois-specific reliability needs rather than simply adding another layer of paperwork.
Cost Signals For Developers And Customers
Cost allocation is the hardest part of energy-only interconnection reform because both undercharging and overcharging have consequences. If interconnection customers do not face the upgrade costs caused by their projects, those costs can migrate to other customers. If projects face uncertain or late-stage upgrade bills, viable projects can withdraw after years of study, leaving planners with fewer replacement resources than expected.
Illinois rules already place many interconnection facility and distribution system upgrade costs on interconnection customers when those costs are caused by the project. The practical challenge is predictability. Developers need earlier cost ranges, clearer study assumptions, and a fair process for shared upgrades. Customers need assurance that network costs are not socialized without a demonstrated system benefit.
Related industrial and infrastructure coverage from Mengo Industries often points to a similar planning lesson: cost responsibility needs to be defined before large capital commitments are made. In the power sector, that principle is especially relevant because transmission upgrades may serve both an individual project and broader grid needs.
- Readiness screens: site control, deposits, commercial milestones, and withdrawal rules can reduce speculative queue volume.
- Transparent cost ranges: earlier upgrade estimates can reduce late withdrawals, though estimates should be updated as studies mature.
- Shared upgrade rules: proportional allocation can be more defensible when several projects drive the same constraint.
- Reliability checks: reforms should distinguish energy injection from dependable contribution during constrained hours.
Reliability Evidence For Illinois Decisions
Resource Adequacy Is A Different Test
The 2025 Resource Adequacy Study referenced in the research record found that the ComEd zone and MISO LRZ4 could lack sufficient in-state or planned resources to meet 2030 requirements under several retirement and demand scenarios. It also identified higher loss-of-load probability and expected unserved energy risks if retiring dispatchable plants are not replaced. Those findings do not establish that outages are inevitable. They do indicate that queue reform should be tested against stressed but plausible resource scenarios.
The distinction is policy-relevant. A project with energy-only rights may supply zero-carbon energy across many hours without being fully deliverable at the system peak. That can still reduce emissions and wholesale energy needs. It may not fully replace a retiring dispatchable plant for planning reserve purposes. Reform should therefore separate two questions: how to interconnect useful resources faster, and how to ensure enough accredited, deliverable capacity remains available.
Market Design And Planning Linkages
Illinois cannot evaluate interconnection rules in isolation from market design. Capacity prices, retirement schedules, load growth, and transmission constraints interact. A related discussion of Illinois market design challenges raises the same planning concern: a policy that lowers one type of cost can raise another if it weakens the signal for dependable capacity or delays necessary network investment.
That does not mean Illinois should require every project to secure full deliverability before connection. Such a rule could slow low-cost energy additions and storage experimentation. It does mean that policymakers should avoid counting non-deliverable resources as if they provide the same reliability value as deliverable capacity. The more retirements concentrate in constrained zones, the more that distinction matters.
energy-only interconnection Policy Reform In Illinois
A measured reform path would keep energy-only interconnection available, but attach clearer readiness, cost, and reliability safeguards. The evidence supports reform of queue process and cost transparency more strongly than it supports abolishing the category. The goal should be to reduce speculative requests, identify network upgrade responsibility earlier, and prevent planning models from overstating the reliability contribution of resources that can inject energy but lack firm deliverability.
For Illinois, the practical test is whether reforms improve buildable project throughput without masking resource adequacy risk. That requires data published on study timelines, withdrawals, upgrade costs, affected constraints, and the operating status of completed projects. It also requires coordination between state interconnection work, MISO and PJM procedures, and Illinois resource planning. The policy case is strongest where reform is treated as an evidence-based adjustment to queue discipline and cost assignment, not as a broad claim that faster interconnection alone will solve reliability concerns.