How to clear a distribution interconnection queue backlog without adding headcount

Across the US, more homeowners, businesses, and developers want to connect rooftop solar, community solar, batteries, small generators, and electric vehicle chargers to the local power grid. Before they can switch on, utility engineers must confirm that they can connect the equipment without overloading the nearby circuit. Utilities call that approval process interconnection.

For most of the last century, utility planners designed local networks to carry electricity in one direction, from a substation to homes and businesses. Now homeowners can send spare solar power back through the same wires. Battery operators can charge from the grid at one hour and discharge to it at another. Engineers must understand how each applicant will affect voltage, equipment loading, and protection systems before they approve a connection.

Utilities group these smaller, local technologies under the term distributed energy resources, or DERs. As more customers adopt them, specialized planning teams must process thousands of applications, from familiar rooftop systems to multi-megawatt projects with complex protection requirements. When those teams fall behind, developers wait to finance and build projects, customers receive little certainty, and states lose time against clean-energy and electrification targets.

Journalists often use "the interconnection queue" for large power projects waiting to join the high-voltage transmission system, which the Federal Energy Regulatory Commission oversees through regional grid operators. Distribution utilities manage local DER queues under state public utilities commission rules and standards such as IEEE 1547. The US Department of Energy supports them through its Interconnection Innovation e-Xchange, known as i2X.

By 2030, the Department of Energy wants utilities to complete more than 99% of applications under 50 kW and reach a median interconnection time below one day. For projects from 50 kW to 5 MW, it wants utilities to complete more than 90% and bring the median below 75 days. Utilities will struggle to recruit because experienced distribution-planning engineers are scarce and utilities take years to develop their expertise.

Utilities can clear the backlog by helping each engineer finish more studies. In many teams, engineers spend more time finding, checking, and rebuilding the inputs than running the analysis itself. The utility must take routine applications off their desks, give them a trusted circuit picture for difficult cases, and stop asking them to repeat completed work.

A process built for far fewer applications

A planner could once handle each interconnection request individually. The engineer collected the application, found the circuit records, checked the equipment, ran the analysis, and sent the result to the developer. Planners could work this way while developers submitted relatively few projects.

Today, staff chase missing fields in one application, copy figures from a PDF in another, and ask an engineer to confirm a standard requirement in a third. As developers submit applications faster, the planning team repeats the same preparation when the next developer proposes to connect a few poles away.

Engineers do more work when developers propose complex projects. Utilities first screen whether an applicant can connect a small, certified system safely. When staff reject an application under those checks, they may conduct a supplemental review before engineers run feasibility and system-impact studies. Engineers then use a facilities study to define required network upgrades. Utilities need to keep routine projects away from the upper rungs of this study ladder because engineers spend more time at each stage.

Screening out the routine projects

A homeowner may apply to connect a certified rooftop solar system on a circuit with ample capacity. Utility engineers have already agreed on the pass-or-fail checks for this familiar connection. Staff should be able to run those approved rules against complete application and circuit data without asking an engineer to reconstruct the case.

States use IEEE 1547 as the national technical foundation for DER interconnection and interoperability. Under rules such as California's Rule 21, utilities review applications through initial and supplemental screens. A utility can encode those fixed rules, record the evidence behind every result, and send only failed or unusual cases to an engineer.

Planners can approve a certified project after staff confirm compliance with the criteria, while protection engineers still judge unusual equipment, weak circuits, and whether the utility can maintain safety and reliability. Developers receive faster decisions on routine projects, and engineers spend their time on cases where they must use professional judgment.

One trusted picture of the circuit

Staff only save time with automated screens when they can trust the information behind them. An engineer may start one study by pulling conductor and equipment records from the geographic information system, feeder loading from advanced metering infrastructure, and protection settings from an engineering model. Staff may then find different units, conflicting equipment records, and updates from different dates.

The engineer must reconcile those differences before running a check. Engineers can spend more time reconstructing inputs than performing the analysis that staff need to move a project forward. Staff can spend 20 to 30 minutes producing one pole model after field capture and office processing. Across thousands of applications, utilities lose substantial engineering capacity in those preparation tasks.

Utility planners should maintain one current circuit picture with feeder loading, conductor details, equipment ratings, and every proposed connection already in the queue. They can reuse the same verified inputs for initial screens and detailed studies and avoid rebuilding a feeder for each application.

Planners also use these inputs to estimate how much new generation or demand engineers can add at a location before the utility needs an upgrade or a closer review. Utilities call that estimate hosting capacity. Developers can consult a current hosting-capacity view before choosing a site, while engineers can use the same information when they assess an application. Utilities must keep the models current because developers may commit capital based on the result and operators must protect the circuit.

Standardizing the data engineers reuse

Staff will undermine the shared circuit picture if they feed it inconsistent information. The utility must define how applicants and internal teams record the connection point, equipment rating, conductor span, attachment height, and expected loading. Staff should check required fields, locations, units, and equipment identifiers as soon as an applicant submits a project.

Staff who validate an application early keep engineers from finding a missing inverter certificate halfway through a study or discovering that two teams recorded the same transformer differently. They also send fewer repeated requests to developers. Once staff approve an input, planners should be able to reuse it in the hosting-capacity view, technical screens, and detailed analysis.

Utilities can then automate with a clear limit. They can apply agreed rules automatically to verified data and preserve how staff reached the result. They should send protection questions and unusual circuit conditions to the engineers who can judge them. Utilities raise throughput this way while remaining accountable for every connection decision.

When a project ahead in the queue withdraws

Engineers may need to repeat an accurate study when a developer ahead in the queue withdraws a project. In a serial queue, planners assess each project on the assumption that earlier applicants will connect. If one developer leaves after receiving a high network-upgrade estimate, engineers may need to recalculate the capacity and cost assumptions for every later project on that circuit.

Utilities can reduce these cascades when staff keep the queue current as developers advance, change, or withdraw projects. Where public utilities commissions allow it, planners can study related projects as a group and assess their combined effect on the circuit. Commissions can also require applicants to show site control or make a financial commitment before they occupy scarce study capacity.

Regulators and utilities must set those readiness requirements carefully. If regulators ask for too little, engineers study speculative projects that developers may never build. If regulators ask for too much, they can exclude credible community-scale developers. Staff need enough evidence that an application is real, while regulators need consistent treatment for comparable applicants.

Fixing intake before the study starts

Applicants create delays before anyone studies the circuit when they submit incomplete forms, email revised attachments, or enter the same project differently across several documents. Engineers then become highly paid administrators because the utility has no reliable way to tell whether a case is ready for review.

Utilities should use a digital portal to require structured fields, validate them on submission, and give applicants and staff the same status record. They should also pass the approved data directly into the screening, circuit, and queue systems. If staff still re-enter every field behind the portal, the utility has moved the form online and preserved the manual work.

The Department of Energy is funding distribution utilities to test this joined-up approach through its Interconnection Queue Management Software program. Participating utilities combine generator and electric vehicle applications with geographic and metering data. DOE wants them to reduce some per-request analysis from days to minutes. Utilities should treat that timescale as the program's goal, then measure what their own engineers achieve.

Throughput per engineer

Leaders need to track how many complete, sound studies each engineer finishes and how much expert time engineers spend on each application. They should separate time spent on engineering judgment from time spent finding data, cleaning applications, repeating screens, and revisiting earlier work. Leaders can then see whether they have removed work from the bottleneck or simply installed another system around it.

Staff should follow a simple operating flow. A developer submits a complete application through one portal. Staff validate the fields, apply approved screens to a current circuit model, and move a routine project forward. When engineers need to use professional judgment, they receive the relevant inputs, prior results, and current queue position together.

Utilities still need experienced engineers because they must protect safety and reliability in unusual cases. Those engineers can finish more studies when they stop rebuilding routine cases from scattered records. A utility can clear more applications with its existing planning team when staff keep intake, circuit data, screening results, and queue changes current. Developers then have a credible route onto the distribution grid.