HomeMy WebLinkAboutF-3. 2013 Electric Reliablility Index Report Information Item F-3
Presented `1 If2 ( 14-
441-1k5. ;
INFORMATION ITEM
TO: HONORABLE CHAIRPERSON AND MEMBERS OF THE AZUSA UTILITY
BOARD
FROM: GEORGE F. MORROW, DIRECTOR OF UTILITIES
DATE: SEPTEMBER 22,2014
SUBJECT: 2013 ELECTRIC RELIABILITY INDEX REPORT
BACKGROUND
Azusa Light & Water — Electric Division collects information about electric system service
interruptions or power outages within its service area. The information is analyzed,tabulated and
summarized into reliability indices to illustrate the performance of a utility electric system during
the period indicated. The reliability index is also used by the Electric Division to plan for and
make improvements to the electric system as needed.
Azusa Light & Water— Electric Division is designated as Reliable Public Power Provider(RP3)
under the American Public Power Association - RP3 Program. As part of its commitment to this
RP3 designation, the Electric Division completed its 2013 Annual Reliability Report and the
results were certified by an outside firm retained by Azusa Light & Water. The 2013 Reliability
Indices for Azusa Light&Water together with industry comparisons are summarized in the table
shown below. The definitions and formula for calculating each index are referenced in a separate
document attached to this report.
2013 Reliability Indices &Average Comparison
(Excluding Major Events)
Index AZUSA Investor Owned Public Power All Industry
SAIDI 18.85 minutes 124.6 124.78 124.66
SAIFI 0.11 1.10 1.15 1.12
CAIDI 169.87 minutes 111.64 110.65 111.31
Azusa Light & Water's 2013 reliability index are within normal & favorable range when
compared with other utilities in the electric industry. The lower SAIDI is indicative of the
Electric Division's pro-active maintenance of facilities to mitigate occurrences of outages and
immediate responses to make repairs and restore power when outages do occur.
Prepared by: Dan Kjar—Electric Distribution Supervisor
F. Langit Jr.—Assistant Director of Electric Operations
Attachment: Definitions and Formulas UB-158
Definitions & Formula for Calculating Reliability Index:
APPA-American Public Power Association
IEEE— Institute of Electrical & Electronic Engineers
SAIDI—System Average Interruption Duration Index
SAIFI—System Average Interruption Frequency Index
CAIDI—Customer Average Interruption Duration Index
1) Azusa defines SAIDI as the sum of the customer interruptions, divided by the total number of
customers served. This is consistent with the IEEE definition.
SAIDI = Sum of Customer Interruption Durations per reporting period
The total Number of Customers Served per reporting period
2)Azusa defines SAIFI as the average number of times that a customer is interrupted during the
year. This is consistent with the IEEE definition.
SAIFI = Total Number of Customer Interruptions per reporting period
Total Number of Customers Served per reporting period
This index is also calculated by the ratio of SAIDI to CAIDI.
3) Azusa defines CAIDI as the average interruption duration time for those customers that
experience an interruption during the year. This is consistent with the IEEE definition.
CAIDI = Sum of customer interruption durations per reporting period
Total number of customers interrupted per reporting period
UB-159