Transmission Development Plan for Northern Ireland (TDPNI)
The TDPNI 2025-2034 sets out the planned transmission network reinforcements over 10 years and involves a capital investment of £1.1 billion into our energy system.
TDPNI 2025-2034 overview
The TDPNI outlines essential upgrades to the electricity grid in Northern Ireland. It will improve reliability and strengthen the electricity network.
The plan fully incorporates information from SONI and NIE Networks’ Joint Programme Management Office (JPMO), which considers the deliverability of the whole portfolio of transmission reinforcement projects. Estimated Completion Dates of all projects in the plan have been informed by the JPMO.
TDPNI 2025-2034 documents
We have now published the Transmission Development Plan 2025-2034.
JPMO Quarterly Updates
The Estimated Completion Dates of all projects in the plan were set at the time of the public consultation in October 2025. The JPMO continuously monitors these dates for all included projects and publishes updates on a quarterly basis.
If you have any queries on the JPMO or the Quarterly updates, please contact JPMO@soni.ltd.uk.
Project documents
There are many documents available detailing different elements of the TDPNI. Browse the list to find out more.
Have your say
Engaging with local communities is essential to our work. We always consult with residents, landowners and stakeholders in grid improvement works.
To speak with us about the Transmission Development Plan for Northern Ireland, please contact us by filling in the contact form below.