The most widely used reliability indexes are SAIFI, CAIDI and SAIDI (pronounced SAY-fee, KAY-dee, and SAY-dee)

• SAIFI stands for System Average Interruption Frequency Index, indicating the average number of outages for the system over a specified time period.

• CAIDI stands for Customer Average Interruption Duration Index, indicating the average duration of a single outage.

• SAIDI stands for the System Average Interruption Duration Index, indicating the average outage duration for the system over a specified time period.

The indexes are mathematically related as follows: SAIDI = (SAIFI) x (CAIDI)

CenterPoint Energy reports reliability index results to the Texas Public Utility Commission (PUCT).

Here are some brief indications of Average Reliability and Power Quality.