Average Service Availability Index

The Average Service Availability Index (ASAI)[1][2] is a reliability index commonly used by electric power utilities. ASAI is calculated as

${\displaystyle {\mbox{ASAI}}={\frac {\sum {N_{i}}\times 8760-\sum {U_{i}N_{i}}}{\sum {N_{i}}\times 8760}}}$

where ${\displaystyle N_{i}}$ is the number of customers and ${\displaystyle U_{i}}$ is the annual outage time (in hours) for location ${\displaystyle i}$. ASAI can be represented in relation to SAIDI (when the annual SAIDI is given in hours)

${\displaystyle {\mbox{ASAI}}=1-{\frac {\mbox{SAIDI}}{8760}}}$

See also

• ASAI
• ASIDI
• ASIFI
• ASUI
• CAIDI
• CAIFI
• CTAIDI
• MAIFI
• SAIDI
• SAIFI

References

1. Yeddanapudi, Sree. "Distribution System Reliability Evaluation". Iowa State University. Archived from the original on 26 December 2011. Retrieved 18 June 2011.
2. Pham, Hoang (8 April 2003). Handbook of reliability engineering. Birkhäuser. p. 514. ISBN 978-1-85233-453-6. Retrieved 21 July 2011.