Decision on Insulation and Interruption Gas Exceptional Event Claim for Scottish and Southern Electricity Networks (SSEN) at Blackhillock
Summary
Ofgem decision on SSEN's Insulation and Interruption Gas Exceptional Event Claim. Sister to the May 2025 SSEN claim publication.
Why it matters
Project-specific exceptional event cost recovery. Routine within the RIIO-2 exceptional-event mechanism.
Areas affected
Memo
Decision on Insulation and Interruption Gas Exceptional Event Claim for Scottish and Southern Electricity Networks (SSEN) at Blackhillock | Ofgem Please enable JavaScript in your web browser to get the best experience. BETA This site is currently in BETA. Help us improve by giving us your feedback . Close alert: Decision on Insulation and Interruption Gas Exceptional Event Claim for Scottish and Southern Electricity Networks (SSEN) at Blackhillock Publication type: Decision Publication date: 18 July 2025 Topic: Energy network price controls Decision for: Insulation and Interruption Gas Exceptional Event Claim for Scottish and Southern Electricity Networks (SSEN) at Blackhillock Print this page Share the page Share on Facebook Share on Twitter Share on LinkedIn Ofgem received a notification from SSEN Transmission on 1 November 2024 regarding a leakage event of 6.115kg of Sulphur Hexafluoride gas (SF6) at its Blackhillock substation, which occurred on 19 October 2024. Companies are financially incentivised to reduce the leakage of Insulation and Interruption Gases (IIG), such as SF6, which are used in some transmission equipment. If an IIG leak occurs on a company's network due to an event that it believes was beyond its reasonable control then the company may make a case to the Authority to designate it an Exceptional Event for all or some of the quantity of IIG leaked during the event; and for it to be excluded from the calculation of the company's revenue reward or penalty. This letter sets out the Authority’s decision to reject SSEN Transmission’s claim for an IIG Exceptional Event that occurred on its network on 19 October 2024. Main document Decision on Insulation and Interruption Gas Exceptional Event Claim for Scottish and Southern Electricity Networks (SSEN) at Blackhillock [PDF, 96.26KB] Print this page Share the page Share on Facebook Share on Twitter Share on LinkedIn Close