Electricity supply reliability budgets 2017

ActewAGL maintains a high standard of reliability in its electricity network. This information sets out the supply reliability budgets for the coming year.

These budgets are averages across all customers, and they give an indication of the likely number of interruptions to supply that an average customer might experience, together with the average duration of interruptions to supply.

Measures

Throughout the world the electricity distribution industry uses three commonly accepted measures for network reliability. These are:

  • CAIDI — customer average interruption duration index
    This is the average duration (in minutes) that a customer is without power when affected by an interruption to supply
  • SAIFI — system average interruption frequency index
    This represents the average number of interruptions that a customer experiences each year
  • SAIDI — system average interruption duration index
    This is the average duration (in minutes) that customers are without power each year

Budgets

For 2017, ActewAGL aims to deliver to its customers a service that is at least as good as shown by the following reliability figures:

Measure

Budget (limits)

Units

Outage time (CAIDI)

74.6

Minutes

Outage frequency (SAIFI)

1.2

Number

Outage duration (SAIDI)

91.0

Minutes

In accordance with the Electricity Distribution (Supply Standards) Code, these budgets exclude interruptions of less than one minute and extended interruptions due to storms. Storms are those interruptions where 10% or more of customers in an area are affected.