Bramford to Twinstead: Project Assessment

Details of outcome

We consulted between 30 January 2026 and 2 March 2026 on our minded-to Project Assessment of National Grid Electricity Transmission’s (NGET) BTNO project under the Accelerated Strategic Transmission Investment (ASTI) framework.

We have considered the consultation responses and decided to provide NGET with a total project allowance of £642.1 million in 2024/25 prices for the delivery of the project against a requested allowance of £702.8 million.

The decision explains our assessment of the submitted costs, the consultation responses and the reasons for the final allowances and risk-funding arrangements. A statutory consultation on the proposed licence modifications needed to give effect to this decision will follow.

Read the full outcome

Original consultation

Consultation description

National Grid Electricity Transmission’s Bramford to Twinstead  is a project under the Accelerated Strategic Transmission Investment (ASTI) mechanism in the RIIO-2 Price Control Framework. At the project assessment stage, we review and ultimately set revenue and outputs associated with delivery of an ASTI project.

As part of The Great Grid Upgrade, National Grid is upgrading the electricity transmission network between Bramford substation in Suffolk and Twinstead Tee in Essex through the construction of 18 km new overhead lines and 11km of underground cable.

The existing electricity network in East Anglia needs upgrading in order to transport all the new renewable and low carbon energy we expect to connect to the network in this area by the end of the decade. NGET are reinforcing the network to meet future demand, boost energy security and help the nation become more self-sufficient.

Who should respond

We would like views from people with an interest in the costs of electricity transmission infrastructure and the transmission owners. We particularly welcome responses from stakeholders impacted by the project.