The two key industry measures of network performance are:
- the average number of outages per customer per year (SAIFI: system average interruption frequency index);
- and the average total duration of outages per customer per year (SAIDI: system average interruption duration index).
In the 2015 financial year we met the SAIFI and SAIDI targets set by the Commerce Commission. On average an Orion customer would have had 1.2 network outages for a total of about two hours without power.
Our network reliability is better than average by New Zealand standards but our network outages are higher than the pre-quake levels. We are on track to restore our network performance to pre-quake levels by 2019.
For the 2016 financial year we aim to have less than 1.2 outages per customers, for a total duration of less than 94 minutes.
'Table of rules'
Our 2016 SAIDI and SAIFI targets are included in our Security of Supply standard, the 'table of rules' that describes the service we aim to provide on our network. It defines whether the power will go out if something fails on our network, and the length of time that customers can then expect to be without power.