For many EV charging projects, utility coordination is the longest and least predictable step in the entire timeline. Installing chargers is straightforward once the utility has approved the new service and any required infrastructure upgrades are in place. Getting to that approval, however, can take months. Our EV charging engineering team manages utility coordination submittals for clients in all 50 states and understands how to navigate the process efficiently.
Why Utility Coordination Is Required
Electric utilities manage their distribution grid to maintain safe, reliable power delivery to all customers within their service territory. When a new customer load of significant size connects to the grid, the utility must verify that the local distribution system can handle the additional demand. EV charging loads, particularly for fleet sites, commercial charging stations, and multifamily projects, can be large enough to affect transformer loading, feeder capacity, and power quality on the distribution circuit serving the site.
The utility coordinates the interconnection of new large loads to protect both the requesting customer and all other customers on the shared distribution circuit. Without this review, a new large load could overload the local transformer, cause voltage problems for neighboring customers, or create reliability issues in the local distribution network.
Even projects that do not trigger an apparent transformer constraint must go through the utility process because the utility must verify conditions, update their system records, and issue any required service agreements. Most utilities have developed dedicated EV charging programs to streamline this process for smaller installations, but large commercial and fleet projects typically go through the full interconnection application process.
What the Utility Needs From the Engineer
The utility’s interconnection application typically requires documentation prepared by a licensed engineer. Standard requirements include a load study showing the proposed connected load, a single-line diagram showing the proposed service and distribution equipment, the point of connection to the utility system, and the proposed metering arrangement. Some utilities require fault current calculations at the point of connection to verify that the proposed protective devices have adequate interrupting capacity.
Utilities increasingly request the engineer’s load study to show not just the connected load but also the expected demand profile over time, particularly for fleet sites. A demand profile showing the charging pattern by hour of day allows the utility to assess the impact on local peak demand and to evaluate whether time-of-use rates might mitigate the grid impact.
The Interconnection Application Process
Pre-Application Meeting
Many utilities offer or require pre-application meetings for large new loads. This is an opportunity to discuss the project scope, identify the utility’s requirements, and understand the timeline before submitting a formal application. Pre-application meetings can save significant time by clarifying requirements up front, preventing multiple rounds of incomplete applications.
Application Submission
The formal application package includes all the engineering documents described above plus the utility’s application form, applicable fees, and any supporting project documentation. We prepare complete application packages for our clients’ EV charging projects so that submissions are accepted on the first attempt and the review clock starts without delay.
Utility Review Phases
Utilities review large load applications in phases. A feasibility study determines whether the proposed load can technically be served from the existing infrastructure. If the feasibility study identifies constraints, a system impact study evaluates in more detail what upgrades are required. A facilities study then scopes the specific construction work the utility must perform and estimates the cost. The customer then decides whether to proceed with the project and typically pays for all or part of the required utility infrastructure upgrades.
Transformer Sizing and the Upgrade Process
When the utility’s review determines that the existing transformer cannot serve the new load, a transformer upgrade is required. The utility selects the replacement transformer size based on the total load served from that transformer including all existing customers plus the new EV load. The customer requesting the new load typically pays for the upgrade or a share of it depending on the utility’s tariff structure.
Transformer procurement and installation timelines are the primary source of multi-month delays on EV charging projects. Standard distribution transformers typically have lead times of six to eighteen months when supply is constrained. The utility’s installation schedule depends on crew availability. Projects that start utility coordination early, even before site design is fully complete, are best positioned to manage this timeline.
How to Reduce Delays
The most effective way to reduce utility coordination delays is to submit a complete, accurate application at the earliest possible point in the project. Incomplete applications are returned for resubmission, which resets the review clock. Applications that significantly understate the load may need to be revised when the actual design is complete, which can restart portions of the review process. Our engineering team prepares utility coordination packages that anticipate the utility’s requirements and provide all necessary documentation upfront.
Frequently Asked Questions
Can we install chargers before utility coordination is complete?
Chargers can be installed on the customer side of the meter before utility coordination is complete, but they cannot be energized and operated. Installing chargers during the utility coordination period can save construction schedule time if the project timeline is tight, but the capital is committed before the utility’s review is finished. We advise clients to understand this risk before proceeding with early installation.
Does every EV charging project require utility coordination?
Small additions of Level 2 chargers served from an existing panel with available capacity may not require utility coordination. Any project that increases the service demand significantly, requires a new service entrance, or requires a new utility connection point will require coordination. The utility’s threshold for requiring review varies, but the conservative approach is to contact the utility whenever adding substantial EV charging load.
How do utilities handle EV charging rates?
Many utilities have developed special rate structures for EV charging, including time-of-use rates that incentivize charging during off-peak hours. These rates can significantly reduce the operating cost of EV charging for fleet operators and commercial site owners. Some utilities offer demand charge waivers or rebates for EV infrastructure that meet program criteria. We can advise on which utility programs may apply to a specific project.
Get Your EV Utility Coordination Started
We prepare complete utility coordination packages for EV charging projects in all 50 states. Submit your project at rightangleeng.com/get-started to get the process moving.
References
Electric Power Research Institute. (2023). Utility EV Infrastructure Integration Guide. EPRI, Palo Alto, CA.
Rocky Mountain Institute. (2022). Charging Up Communities: Managing Grid Impacts of EV Deployment. RMI.
National Fire Protection Association. (2023). NFPA 70: Article 230: Services. Quincy, MA.