What Is a Grid Interconnection Queue?

The bottleneck that is delaying billions of dollars in data center and renewable energy projects — and what it means for power demand.

If you want to build a data center that draws more than about 10–20 MW, you cannot simply connect it to the nearest power line. You must go through the grid interconnection queue — a process run by regional transmission organizations (RTOs) and independent system operators (ISOs) that determines whether, when, and at what cost your project can connect to the transmission grid.

Today, this process is severely broken. As of mid-2026, interconnection queues across the United States contain over 2,000 GW of pending generation and load capacity — more than double the total generating capacity of the entire US electric grid. The median timeline from queue entry to commercial operation is now 3–7 years, and some projects wait a decade or more.

How Interconnection Works

The interconnection process, while complex, follows a general sequence across most RTOs and ISOs:

1. Feasibility Study: The system operator performs a high-level assessment of whether the proposed interconnection can be accommodated without major grid upgrades. This typically takes 60–120 days.
2. System Impact Study: A detailed engineering analysis evaluates the specific grid upgrades required — new transmission lines, substation expansions, transformer additions, and protection systems. This phase can take 6–12 months.
3. Facilities Study: The final engineering phase produces detailed cost estimates and construction timelines for required upgrades. Duration varies from 6–18 months.
4. Interconnection Agreement: The project owner signs a legally binding agreement with the utility/RTO specifying cost allocation, construction responsibilities, and milestone dates.
5. Construction and Energization: Upgrades are built and the interconnection is energized. Large transmission upgrades can take 3–5+ years to construct.

The total timeline from initial application to energization now averages 5–7 years for projects requiring significant transmission upgrades. For 500 MW+ data center campuses, it can stretch to 10 years or more.

Why the Queue Is Backlogged

The interconnection queue backlog has multiple causes, all of which compound one another:

1. Surge in Renewable Energy Projects

The Inflation Reduction Act and state renewable portfolio standards triggered an avalanche of wind, solar, and battery storage interconnection requests. In 2025 alone, US RTOs received over 1,000 new interconnection requests totaling more than 500 GW. This volume overwhelms the system operators' study capacity.

2. Data Center Load Growth

Data center load requests — which barely registered in queues five years ago — now represent a significant and growing share. Unlike generation projects, load interconnections require the utility to identify and fund upstream grid reinforcements. A single 500 MW data center can trigger $50–200 million in transmission upgrades.

3. Serial Queue Processing

Most RTOs process interconnection requests on a first-come, first-served basis. Projects that enter the queue later must wait for earlier projects to complete their studies (or withdraw) before their own studies can begin. This serial processing model creates a bottleneck that grows worse as the volume of requests increases.

4. Resource Constraints

RTOs, ISOs, and transmission-owning utilities face severe engineering and project management staffing shortages. There simply are not enough qualified power systems engineers to study 2,000 GW of interconnection requests.

The FERC Reforms

Recognizing the crisis, the Federal Energy Regulatory Commission (FERC) has taken several major actions to reform interconnection:

Order No. 2023 (2023–2024)

FERC's landmark interconnection reform order requires RTOs and ISOs to transition from serial to cluster-based processing. Instead of studying projects one by one, clusters of projects in the same region are studied together, allowing for more efficient identification of shared grid upgrades. Order 2023 also imposes stricter financial deposits and milestone deadlines to weed out speculative projects that never get built.

Order No. 2023-A (2025)

FERC's follow-up order addressed implementation challenges and clarified the transition timeline. It also required RTOs to adopt "first-ready, first-served" principles — projects that are more advanced in their development should be prioritized over those that simply entered the queue earlier.

Load Interconnection Reform (Pending, 2026)

FERC has opened a proceeding to specifically address the growing challenge of data center and industrial load interconnections. The commission is considering whether load interconnections should follow a different process than generation interconnections, given their distinct characteristics and impact on transmission planning.

What This Means for Data Center Projects

Every project we track on DataPowerDemand is affected by interconnection timelines:

• Project Titan (1,200 MW, Virginia): Filed its PJM interconnection request in Q2 2026. With PJM's current queue, initial studies may take 12–18 months, with construction of required transmission upgrades potentially extending to 2028 or beyond.
• Texas AI Corridor (800 MW, Texas): Filed with ERCOT in Q1 2026. ERCOT's faster (but less thorough) interconnection process offers some relief, but the scale of upgrades required — including a new 345 kV substation — still implies a 3–5 year timeline.
• Ohio River Energy Park (500 MW, Ohio): Entered PJM's pre-filing stage in May 2026. The project's proposed behind-the-meter gas generation strategy is designed specifically to bypass queue constraints by self-supplying power.

The "Behind-the-Meter" Alternative

Increasingly, data center developers are exploring behind-the-meter generation — building on-site power plants that do not require full interconnection study under RTO rules. The Ohio River Energy Park's natural gas co-location is one example. Others include nuclear-powered data centers (with small modular reactors) and grid-defection strategies using dedicated renewable generation plus battery storage.

While these approaches can bypass the queue, they introduce their own complexities — fuel supply, emissions permitting, gas pipeline interconnection — and may create stranded assets if grid interconnection is eventually needed.

Key Takeaways

• Interconnection queues contain over 2,000 GW of pending capacity — more than the entire US grid
• Median timeline from queue entry to energization: 3–7 years
• Data center load requests are a growing share of queue volume
• FERC Order 2023 transitions RTOs to cluster-based processing
• Behind-the-meter generation is emerging as a queue-bypass strategy
• Transformer shortages compound interconnection delays (read why)