Application Guidance for the Third Cap and Floor Window for Electricity Interconnectors


Publication date

Industry sector

Transmission Network

This document sets out the cap and floor regime application process for the upcoming third application window for new regulated interconnectors, following our Interconnector Policy Review decision from December 2021. We have included guidance for potential applicants on eligibility and submission criteria for the Initial Project Assessment stage.

We also propose a new timelines and incentives framework for the third application window to improve our treatment of project delays. Our preliminary positions are outlined in this document, which will be subject to further consultation.

The third window will be open from 1 September 2022 to 10 January 2023. On 14 October 2022 Ofgem revised the “Application Guidance for the Third Window” to align with the updated window dates for the third window. Please note that we are accepting applications for the third window and the Multiple Purpose Interconnector (MPI) pilot regulatory framework in tandem, more detail on the MPI pilot can be found in a separate guidance document.

Further details on our needs case assessment framework for the Initial Project Assessment stage, and how we plan to target the third window was published in summer 2022.

Subsidiary guidance dated 14 October 2022 titled “Supplementary application submission guidance for Third Window and the MPI Pilot” offers clarification on the submission of documents.

Please send any feedback, questions, or completed applications to .

On 31 August 2022 Ofgem contacted stakeholders to inform them of our decision to provide one new high level cost assessment template for all applicants of the third investment round for interconnectors, including the MPI Pilot. As a result of the consolidation of the MPI Pilot and Third Window templates, there were some inconsistencies, which required correction. These have been documented in the supplementary application submission guidance and a revised version of the cost assessment template has been provided on 14 October 2022.