Distribution Network Operator (DNO)
A Distribution Network Operator (DNO) is the company that owns and manages the local electricity distribution network in a specific UK region, delivering power from the national grid to homes and businesses via cables, substations, and related infrastructure.
A Distribution Network Operator - or DNO - is the company responsible for owning and operating the local electricity distribution network in a specific geographic area. The DNO manages the physical assets that deliver power from the national transmission grid to homes, businesses, and commercial premises: cables, substations, transformers, service heads, and the street-level infrastructure that connects individual properties to the wider grid. In the UK, there are six regional DNOs covering England, Scotland, and Wales: Electricity North West, Northern Powergrid, Scottish & Southern Energy Networks, UK Power Networks, SP Energy Networks, and National Grid Electricity Distribution.
The DNO is not your electricity supplier. Your supplier sells you energy under a commercial contract and manages your billing. The DNO is the company that owns and maintains the physical infrastructure through which that energy travels.
Why the DNO Matters for Renewables and Electrical Installers
For businesses installing solar PV, battery storage systems, heat pumps, or EV charging points, the DNO is a key stakeholder. Any system that exports electricity to the grid, or that places significant new demand on it, requires the DNO to be notified or formally approve the connection. This is governed by engineering recommendations G98 and G99. G98 applies to smaller generation and storage systems - typically below 16 amperes per phase - and requires notification only. G99 applies to larger systems and requires a formal application and written approval before the system can be commissioned.
The process has a direct impact on project timelines. G99 applications can take four to eight weeks to process, and if the DNO identifies that local network capacity needs reinforcing, connection costs and lead times can increase substantially. Experienced installers factor DNO engagement into their project programme from the pre-survey stage, not as an afterthought after the quote is accepted.
DNO vs energy supplier - know the difference
Installers and customers sometimes confuse these two. The DNO controls what power is available at a site and under what conditions; the energy supplier manages the billing contract. When installing renewables or EV charging infrastructure, it is the DNO - not the energy supplier - that needs to approve or record the new connection.
DNO Notifications and Applications in Practice
For most residential and small commercial solar or EV charging installations, the process is relatively straightforward. The installer submits the appropriate G98 or G99 notification on behalf of the customer, typically through the DNO's online portal. The Energy Networks Association (ENA) reported in 2026 that 95% of EV charger G98 notifications are approved within five working days.
Larger commercial projects - including battery energy storage systems, fast EV charging hubs, or solar arrays above 50 kWp - may require a more detailed G99 application. This can involve technical drawings, protection relay settings, earthing arrangements, and metering specifications. In these cases, early engagement with the DNO during the design stage avoids costly redesign after equipment has been ordered or, worse, after installation has begun.
Common in
Frequently asked questions
Ready to put this into
practice?
Book a free demo and see how Zigaflow fits your team.