Interconnection Queues
| Technology type | Renewable energy generation |
|---|---|
| Project name | Varies by specific application |
| Original use | Integrating new power generation into the electrical grid |
| First created | Late 20th century |
| Typical capacity | Varies by project |
| Primary function | Manage grid connection requests |
| Process outcome | Interconnection agreement or study |
Origin and history
The formalized process known as an interconnection queue originated in the United States in the late 1990s and early 2000s alongside the restructuring of electricity markets. Its development was driven by the need to manage a growing number of requests from independent power producers seeking to connect new generation facilities to the high-voltage transmission grid. Prior to this period, utility-led, integrated planning dominated, and there was less need for a standardized, open-access application process. The establishment of Regional Transmission Organizations (RTOs) and Independent System Operators (ISOs) created the administrative framework necessary to implement these queues. The queue process became a critical component of open-access transmission tariffs mandated by the Federal Energy Regulatory Commission. Its structure has evolved over decades to address increasing complexity, though the core function of managing connection requests remains.
What it is for
An interconnection queue is an administrative process managed by a transmission system operator to evaluate and process requests to connect new electrical generation or storage projects to the grid. Its primary purpose is to ensure system reliability by studying the potential impacts of each new project on the existing transmission network. The process determines the technical requirements and necessary grid upgrades, known as network upgrades, to safely accommodate the proposed new power source. It also establishes a fair, sequential order for processing these requests, as projects are typically studied in the order they are submitted. Furthermore, the queue allocates the financial responsibility for those required network upgrades among the various interconnection customers. Ultimately, it serves as the formal gateway for any new generator or storage asset to reach commercial operation and deliver electricity to the wholesale market.
Overview
An interconnection queue functions as a managed list, often years long, of proposed generation and storage projects awaiting technical and economic assessment. A project developer submits an application with detailed specifications, paying a fee to enter the queue at a specific point of interconnection on the transmission system. The system operator then conducts a series of progressively detailed studies, starting with a feasibility study and moving to a system impact study and finally a facilities study. These studies identify potential issues like thermal overloads, voltage violations, or stability concerns that the new project might cause. The output is an interconnection agreement that stipulates the specific upgrades needed, their cost, and the schedule for completion. The entire process, from application to commercial operation, routinely takes multiple years due to the volume of projects and complexity of studies.
What to know
Queue positions are valuable but not guarantees of project completion, as many projects withdraw due to economic, siting, or permitting challenges. The studies often reveal that substantial and expensive network upgrades are required, the cost of which is typically borne by the interconnection customer, fundamentally impacting project economics. Delays are endemic to the process, caused by study backlogs, supply chain constraints for upgrade components, and the need to study clusters of projects together. The queue process is separate from securing a power purchase agreement or market participation rights, which are commercial necessities that often depend on successful interconnection. Different regional transmission organizations have distinct queue procedures, study timelines, and cost-allocation methodologies, requiring localized expertise. Understanding the queue dynamics, including upgrade cost caps and milestone deadlines, is essential for developers to manage financial risk and project timelines effectively.
Common questions
What determines a project's place in the queue? A project's place is generally determined by the date its complete application and deposit are received, though some regions have moved to cluster studies that group projects from similar application windows. How long does the entire interconnection process take? The timeline varies by region but typically spans from three to over five years from application to commercial operation, not including prior development work. Who pays for the required grid upgrades? The interconnection customer is typically responsible for funding the network upgrades identified in the studies, though costs may be shared under certain conditions if later projects benefit. Can a project lose its queue position? Yes, projects can be terminated from the queue for failing to meet specific financial or technical milestones outlined in the interconnection procedures. What is the difference between the interconnection queue and a capacity market? The queue is a technical process for grid connection, while a capacity market is a financial mechanism to procure future system reliability; a project must typically complete the queue to participate in a capacity market. Why are so many projects in queues never built? Many projects fail due to the high cost of network upgrades, inability to secure financing or a power purchase agreement, or losing economic competitiveness during the lengthy study period.
Pros and cons
A primary advantage of the queue system is that it provides a structured, transparent, and non-discriminatory process for grid access, replacing ad-hoc utility negotiations. It systematically identifies technical constraints and necessary infrastructure investments, which is crucial for maintaining grid reliability as the generation mix changes. However, a significant drawback is that it has become a major bottleneck for deploying new energy resources, with timelines that are often incompatible with policy goals or market signals. The process can be prohibitively expensive for developers, who face uncertain and sometimes catastrophic network upgrade costs only revealed deep into the study process. A common mistake is for developers to enter the queue prematurely without sufficient site control or preliminary engineering, leading to costly delays or withdrawal. Many regulators and system operators regret that the existing process is sequential and slow, failing to efficiently integrate the volume of projects needed for energy transitions, prompting ongoing reforms.
Who it suits
The interconnection queue process primarily suits large-scale generation and storage project developers with substantial financial resources and technical expertise to navigate its complexity and cost risks. It is a necessary path for utility-owned projects, as well as independent power producers aiming to sell electricity into wholesale markets or to corporate buyers via power purchase agreements. The process is particularly critical for renewable energy developers, such as those building wind and solar farms, whose viable locations are often in areas with constrained transmission infrastructure. It also suits merchant generation developers who rely on market prices, as queue completion is a prerequisite for market participation. The structure does not suit small-scale or distributed generation projects, which typically follow a simplified, faster process for connecting to the distribution grid. Ultimately, it suits entities with the patience and capital to endure a multi-year, financially uncertain administrative and engineering undertaking.