The Electricity Supply Emergency Code (ESEC) describes steps which the UK Government could take to deal with a civil or electricity supply emergency, and the actions which companies in the electricity industry should plan to take and which may be required to deal with such emergencies.

In the event of an emergency, ESEC enables an equal distribution of electricity supply to customers as far as reasonably practicable, whilst ensuring that pre-designated Protected Sites maintain supplies for as long as possible.

The rota load scheme provides 18 plans, that set out the level and sequence of load block disconnections and reconnections.