UnitedKingdom Annexe 3 - Note 3

The supply of drinking water or electricity to networks which provide a service to the public by a procuring entity other than a contracting authority shall not be considered as an activity within the meaning of paragraphs (a) or (b) of this Annex where:

a the production of drinking water or electricity by the entity concerned takes place because its consumption is necessary for carrying out an activity other than that referred to in paragraphs (a) to (f) of this Annex; and

b supply to the public network depends only on the entity's own consumption and has not exceeded 30 per cent of the entity's total production of drinking water or energy, having regard to the average for the preceding three years, including the current year.