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Energy — renewables & grid
Energy — renewables & gridRenewables & grid

Bramford to Twinstead 400kV Reinforcement

Bramford, Suffolk to Twinstead, Essex, England · 2025–2029 (Planning consent granted Sep 2024, main construction expected to start 2025, operational by 2029) [1] [2] · Estimated £700 million (overall project); £363 million (Balfour Beatty contract) [3] [4]

The judgement call

Account-gated at launch

The project received Development Consent Order (DCO) approval. Extensive public consultation was undertaken regarding the route and visual impact, leading to a combination of overhead lines and underground cabling. [2] [5]

Key engineering challenges

Construction of new 400kV overhead lines and underground cabling across diverse terrain. [5] - Managing environmental and visual impact, particularly with the introduction of new pylons and undergrounding sections. [5] - Integrating new high-capacity transmission infrastructure into the existing electricity network. [1]

Project facts

Client / owner
National Grid
Lead contractor
Balfour Beatty (for overhead lines and underground cable) [4]
Lead designers
Project type
new build / upgrade
Scale
Approximately 29 km in length (18 km new 400kV overhead lines, 11 km underground cable); 400 kV [1] [5]
Disciplines
electrical; civil; structural; environmental; project management
Standards & frameworks
Development Consent Order (DCO), Planning Act 2008.

Sources: National Grid: Bramford to Twinstead (https://www.nationalgrid.com/the-great-grid-upgrade/bramford-to-twinstead) [1] - Ofgem: Bramford to Twinstead: Project Assessment (https://www.ofgem.gov.uk/consultation/bramford-twinstead-project-assessment) [2] - LinkedIn: Green light for plans to reinforce electricity transmission network (https://www.linkedin.com/pulse/green-light-plans-reinforce-electricity-transmission-network-dtckc) [3] - Balfour Beatty: Balfour Beatty awarded £363 million Bramford to Twinstead electricity network reinforcement scheme (https://www.balfourbeatty.com/media-centre/latest/balfour-beatty-awarded-363-million-bramford-to-twinstead-electricity-network-reinforcement-scheme/) [4] - Suffolk County Council: Bramford to Twinstead (https://www.suffolk.gov.uk/planning-waste-and-environment/major-infrastructure-projects-including-nsips/nsips-in-suffolk/bramford-to-twinstead) [5]