IN Brief:
- National Grid has started a £2.5m electricity network reinforcement in Barnstaple, North Devon.
- Two kilometres of underground cable will connect Barnstaple Quay and Rock Park substations, with directional drilling through Rock Park.
- The scheme includes substation upgrades and ducts for future work, with completion scheduled by April 2027.
National Grid Electricity Distribution has begun a £2.5m reinforcement of the electricity network in Barnstaple, North Devon, including two kilometres of new underground cable between substations at Barnstaple Quay and Rock Park. The scheme is intended to maintain dependable supplies for existing customers while providing capacity for additional connections and rising electricity use. It also involves work at the Rock Park substation and the installation of spare ducts for future reinforcement.
The work follows a route beside the River Taw through The Strand, The Square, Commercial Road and Taw Vale, connecting the Barnstaple Quay and Rock Park substations. Contractors are carrying out civil and electrical activity across a busy part of the town, where access to businesses, pedestrians and road users must be maintained. National Grid says it has worked with the local authority on the programme to manage noise and disruption while the new underground link is installed.
A cable reinforcement has to be designed as part of the network that will receive it. The new conductors, insulation and terminations must be compatible with the switching and protection arrangements at the two substations, while their carrying capacity will depend on the system design and operating conditions. Rock Park substation equipment is being upgraded alongside the cable installation, allowing the two parts of the scheme to be commissioned as an integrated connection between existing distribution sites.
The route includes Rock Park, where contractors are using directional drilling to install cable infrastructure beneath the ground without excavating a continuous open trench. In a park, that technique can preserve more of the surface, paths and landscaping than conventional trenching along the whole route. Drilling still requires access and working areas for the equipment and the cable installation process, but it changes the distribution of excavation and can help reduce disruption to users of the green space.
At Rock Park substation, the new cable will connect to upgraded electrical equipment. Before energisation, the operator will need to coordinate circuit identification, switching, protection and the electrical tests appropriate to the installed equipment. Any connection to an existing network also requires safe isolation and restoration procedures to protect workers and maintain supplies during planned works. The Rock Park substation modifications therefore form an essential electrical interface between the new underground route and the existing network.
National Grid is installing additional cable ducts alongside the current works. Empty ducts provide a prepared underground pathway for future circuit installations, subject to the eventual network design and available space. Including them in the present excavation programme can avoid reopening parts of the same route when later reinforcement is needed. Their installation is a civil-engineering provision, while any future electrical circuit would require its own cable installation, termination and commissioning programme.
The network investment will also help provide capacity for the 345-home Mariners Haven development in Ilfracombe. Although the cable work is concentrated in central Barnstaple, the upgraded distribution infrastructure supports connections and demand across the surrounding North Devon network. New housing adds electricity requirements for lighting, appliances and other services, with low-carbon heating and electric vehicle charging also affecting how those loads develop. National Grid expects the reinforcement to help serve existing customers as well as the planned additional connections.
The network must be able to serve changing demand without exceeding the safe operating limits of cables and electrical plant. Current flows produce heat in conductors, while switches, joints and transformers have ratings that govern the loads they can carry. Reinforcement can redistribute load or increase the available transfer capability between network points, depending on the configuration. The presence of a new cable alone does not establish the final capacity benefit; the connected substations and their operating arrangements must also be considered.
Work in streets and public spaces requires different installation methods along the route. Directional drilling reduces the extent of open excavation through Rock Park, while town-centre sections involve coordinated access, noise management and safety controls. National Grid has described close working with the local authority and measures to maintain business access during construction. The programme will combine cable installation with electrical changes at Rock Park substation before the upgraded connection can be returned to normal network service.
The delivery programme runs through installation, substation modifications and appropriate testing ahead of completion by April 2027. Cable pulling and termination will have to follow the civil works, and the existing network will need controlled switching during the commissioning process. Additional ducts are being installed as part of the same works so that later reinforcement can use the prepared routes where suitable. The current project will therefore deliver the cable reinforcement and prepared routes as distinct elements of the same construction programme.
The £2.5m project is intended to strengthen power supplies in Barnstaple while accommodating development elsewhere in North Devon. Underground cable between the two named substations, associated Rock Park equipment and spare ducting form the confirmed scope. Completion is scheduled for April 2027, after the remaining cable installation and substation work.
