Authority decision on SP Transmission SF6 Exceptional Event claim

Decision

Publication date

Industry sector

Transmission Network

Electricity transmission companies are financially incenticivised to reduce the leakage of sulphur hexafluoride (SF6), a potent greenhouse gas used in some transmission equipment. As some leakage of SF6 will be expected from normal operating assets, a target quantity of SF6 (measured in kg) leaking from all network assets is set for each company (based on its network characteristics). Each company is then rewarded or penalised through a revenue adjustment based on how it performs each year against the target.

If a leak of SF6 occurs on a company's network due to an event that it feels was beyond its reasonable control then the company may make a case to the Authority to designate it an Exceptional Event and for all or some of the quantity of SF6 leaked during the event to be excluded when we calculate the company's revenue reward or penalty.

This letter sets out the Authority's decision in relation to two SF6 Exceptional Event claims received from SP Transmission. The first in relation to SF6 leakage on their network between July 2012 and September 2013; the second in relation to leakage in January 2014.