Skip to main content

DNOs

Distribution Network Operators (DNOs) operate the UK’s electrical network infrastructure. Their role is to manage the provision of electrical power to all homes, businesses, and other properties within their area of coverage.  

There are multiple DNOs in the UK, each managing a clearly defined geographic area. Responsibility for Scotland’s electricity network is divided between Scottish Power Energy Networks (SPEN) and Scottish and Southern Electricity Networks (SSEN).  

The costs associated with DNO network connections are a critical consideration in the development of charging infrastructure. This is the case whether you’re installing at a depot for servicing fleet vehicles or at locations supporting the expansion of the public charging network.  

You will have to engage with the DNO when arranging new connections or changes to an existing connection to support the installation of charge points. It is essential to engage with the DNO as early as possible in the planning phase, as their involvement will influence the timescales, logistics, and cost of the project. Long DNO lead times are frequently cited as a cause of delays to charging infrastructure projects. 

Capacity charges

Standardised ‘capacity charges’ are applied for connections above a certain size. These cover the cost of ensuring power corresponding to the connection size is constantly available to the site. These charges apply irrespective of how much energy is used.  

The topics outlined in this toolkit can all help minimise the size of any new connection you will need at a site, therefore reducing the size of capacity charges, you will incur.  

Capacity charges are often included within Distribution Use of System Charges (DUoS), with the charge applied depending on the time of usage and the voltage level of the connection.  

In April 2023, Ofgem’s Access and Forward-Looking Charges Significant Code Review (or ‘Access SCR’) came into effect. Access SCR changed the payment for grid upgrades, meaning you will no longer pay for network reinforcement costs upstream of your connection unless your connection triggers a High-Cost Project Threshold. You will now only pay for downstream upgrades or sole extension assets to your site.  

Case Study: Project PACE

Scottish Power Energy Networks, in partnership with Transport Scotland, Scottish Government, North Lanarkshire Council and South Lanarkshire Council, investigated a model for DNO-led charging infrastructure planning from 2019 to April 2021. 

Traditionally, local authorities lead the process of identifying charging infrastructure sites by prioritising locations they anticipate will best serve members of the local population. However, as this is done without close sight of the electrical network, the chosen locations may be challenging (and expensive) for the DNO to accommodate. 

Project PACE identified 44 sites within North and South Lanarkshire best suited for charge points and installed 167 charge points. They optimised site identification by taking into account electrical network considerations during the location selection process. This streamlined the connection process, saving money while still ensuring the chosen locations aligned with local charging needs.  

Project PACE delivered savings of £1.3 to £2.6 million in expected connection costs across its 44 sites.