The Electricity Authority has a System Operator Rolling Outage Plan. This requires participants to prepare Participant Rolling Outage Plans. The purpose of such plans is to specify the actions that would be undertaken to reduce the consumption of electricity when a supply shortage is declared by the System Operator.

Events that could lead the Electricity Authority to declare a supply shortage can be generally categorised as immediate events that occur with little or no warning, or developing events that evolve over time.

Wellington Electricity's Participant Rolling Outage Plan details the planned actions for both categories of events.

Reducing consumption by disconnecting consumers would be the last resort, after all other forms of reduction had been employed. While this is Wellington Electricity’s planned response, a change in circumstances or network conditions may require the plan to be adjusted to suit operating conditions at the time.