This guide is designed to help your business successfully navigate the process of engaging with your Distribution Network Operator (DNO). By following this advice you can ensure your electric vehicle (EV) fleet transition is efficient, cost-effective, and avoids costly delays.
Transitioning to an electric vehicle (EV) fleet is a major step toward reducing emissions and future-proofing your business. But it’ll also have a big impact on your electricity demands.
Industry forecasts suggest that by 2030, electric vehicles could increase U.S. electricity demand by as much as 185 terawatt-hours—roughly 2.5% to 4.5% of the nation’s total usage.
So, to accommodate this demand and reliably power your charging infrastructure, you’ll need to engage with a key player: your local Distribution Network Operator (DNO).
DNOs are responsible for delivering electricity from the national grid to homes and businesses. If your depot or site needs additional capacity to support EV charging, the DNO is who makes that happen.
Engaging early with your DNO helps avoid delays, ensures accurate planning, and gives your company project the best chance of success.
Understanding the role of DNOs
DNOs operate and maintain the electricity distribution infrastructure in specific regions.
They don’t generate electricity or supply it commercially, but own the cables, substations, and equipment that power your buildings.
When you install EV charging stations, especially multiple units for a fleet, you’re increasing the load on the network.
If the site’s existing capacity isn’t enough, you’ll need approval, infrastructure upgrades, or new connections from the DNO.
There are six (seven if you count NI Electricity for UK) principal DNOs in the U.K. and an increasing number of licensed independent DNOs (iDNO) and similar utilities in the U.S. Each one governs how businesses can install EV chargers at scale while protecting grid integrity.
For any commercial EV charging setup, working with your DNO is not optional, it’s essential.
Who is my DNO?
In the United Kingdom, the electricity network is divided into regions, each managed by a specific Distribution Network Operator. The six main operators are:
- Electricity North West
- Northern Powergrid
- Scottish & Southern Energy Networks
- UK Power Networks
- SP Energy Networks
- National Grid Electricity Distribution
Fleet operators can quickly identify their local DNO by using the Energy Networks Association’s “Who’s my network operator?” online tool. This step is important, as the right DNO must be contacted before any large-scale EV charger installations or depot upgrades can be approved.
Unlike energy suppliers, DNOs cannot be chosen or switched. They are fixed by geography, and every site must work with the operator responsible for its region.
Planning your EV fleet charging
Before contacting a DNO, it’s crucial to understand what your fleet needs.
Several factors influence the size and type of connection you’ll require:
- Number of vehicles in your fleet today, and how this might change over time
- Types of chargers you plan to install
- Charging schedules (overnight, staggered, or rapid turnover)
- Current site power capacity and availability of existing infrastructure
If your charging needs exceed your site’s current capacity, you’ll require a network upgrade. That’s when DNO power supply discussions begin.
The more accurate your estimates, the easier it is for the DNO to plan and support you. This step also helps avoid unnecessary costs and future limitations.
The DNO engagement process: steps and best practices
Engaging with your DNO follows a clear set of steps. We’d always recommend starting this as early as possible, and ideally during the design and feasibility phase of your EV transition plan.
Step 1: Initial inquiry
Submit a request for information through the DNO’s website or portal. Most now offer pre-application advice sessions, called DNO surgeries. These are usually short sessions that allow you to discuss project feasibility and possibly rough cost estimates. The more information about your scheme you can provide up front, the more useful this session will be.
Step 2: Formal Application
Complete a DNO application form to provide key information, including your business name, site address and site ownership boundary map, , number, makes and models of charge points, electrical schematic drawings for the charge point installations and anticipated timelines. The applications will also be slightly different depending on whether you are asking for an increase in load for an existing connection or for a brand-new connection in a new location.
Step 3: Receive a quotation
The DNO will assess your site, determine available capacity, and issue a quote if upgrades or a new connection are needed, or a zero quote if no works are needed. Either of these will form a connection agreement which must be signed before connection of the equipment can take place. This may take around 6-8 weeks, and sometimes around 8-12 weeks for more complex applications.
Step 4: Accept and schedule works
A quote involving works will be split into Contestable and non-Contestable works. Contestable works are those you can carry out yourself using a qualified third party, while non-contestable are works that must be carried out by the DNO. Once you agree the arrangement and accept the quote, the DNO will arrange for works to begin. Lead times can vary based on network constraints, complexity and availability of equipment.
To streamline the process:
- Use a trusted installer familiar with DNO notification rules and DNO authorisation requirements
- Align planning applications with your DNO timeline
- Be proactive in following up and providing technical details
In addition, you can work with partners like Hitachi ZeroCarbon to support your DNO engagements, ensure it aligns with your EV fleet transition plan, and ensure new connections or capacity upgrades are what’s best for your business.
Overcoming grid and capacity challenges
Not all sites have enough spare capacity for large-scale EV charging installations.
Common issues include:
- Network constraints in densely populated or industrial areas
- Reinforcement needs, such as new substations or cabling
- Long lead times for delivery of physical infrastructure
A looped supply shares a single cable with a neighbouring property. This common setup often lacks the capacity for EV charging and will likely require an upgrade.
To solve these, your DNO may propose:
- Smart charging solutions to stagger energy demand
- Load management systems to avoid exceeding limits
- Alternative connection points, such as linking to a nearby substation
Working closely with your DNO ensures you’re aware of potential constraints and gives you time to adapt your project accordingly.
The value of data and digital tools
Many DNOs now offer interactive digital maps that show available capacity in specific areas. These tools help businesses plan locations, scope infrastructure, and avoid grid bottlenecks.
For example, UK Power Networks offers a heat map for EV charging capacity. In the U.S., utilities like PG&E and Con Edison provide similar network planning resources.
These tools can guide decisions about:
- Where to locate depots or charging hubs
- Whether to apply for full upgrades or use managed load strategies
- How to future-proof installations based on network growth plans
Cost considerations for fleet operators
Engaging with a Distribution Network Operator can also involve direct costs. For fleets, the most common charges include upgrades to main fuses, new substations, or reinforcement works on the electricity network.
If your depot relies on a looped supply, the DNO may need to unloop the cable before approving EV charger installations. This process can be time-consuming and expensive.
Costs vary by DNO and by project scale. For example, National Grid Electricity Distribution may apply different charges compared with UK Power Networks, depending on regional capacity and the scale of infrastructure changes required.
Budgeting for these costs early avoids unexpected financial strain and ensures fleet transition planning remains on track.
Building a collaborative relationship
Engaging with your DNO early in the EV transition journey saves time, reduces costs, and keeps your project on track. A collaborative, transparent relationship with your DNO ensures your infrastructure is safe, compliant, and scalable.
As EV fleets grow, so does the need for proactive planning. To support this journey, Hitachi ZeroCarbon offers EV fleet management solutions designed to align charging infrastructure with operational goals.
For businesses starting small or scaling fast, we offer EV fleet charging solutions to help you plan, install, and manage infrastructure with long-term efficiency in mind.
Frequently Asked Questions
Why do I need to engage with my Distribution Network Operator?
It’s compulsory. Your DNO owns and operates the local electricity network. Any significant increase in power demand, like a fleet of electric vehicles, requires their approval and often a physical upgrade to the network connection to ensure safety, reliability and compliance. Not engaging with them can result in forced disconnection, fines and an unsafe installation.
What’s the biggest mistake businesses make in this process?
Starting too late. Engaging your DNO late is the most common cause of major project delays and unexpected costs.
The DNO’s planning and construction phases can take many months and engaging late can push your entire EV fleet rollout back by a year or more, disrupting your operational and sustainability goals.
What’s a “looped supply”?
A looped supply is a network configuration where two properties share a single service cable from the local substation. While cost-effective for standard connections, it can’t cope with high-demand applications like EV charging.
Upgrading a looped supply is a common requirement for fleet transitions and can be a long process, so it’s essential to engage with your DNO early.
Glossary
- Distribution Network Operator (DNO): The company licensed to distribute electricity in a specific area. They own, operate and maintain the electricity poles, cables and substations that get power to your business.
- Electricity Supply: The provision of electrical power to a property, managed by an electricity supplier but delivered via the DNO’s physical network.
- Looped Supply: A network arrangement where two or more properties are connected to the main network via a single cable that ‘loops’ from one property to the next. This can limit the available power for each property.
Contestable Works: Elements of a new electricity connection that can be carried out by a DNO-accredited independent contractor, rather than the DNO itself. This can sometimes save costs.