Key Performance Metrics
Service Reliability
The North American Electric Reliability Council's definition of reliability encompasses two concepts: adequacy and operating reliability. Adequacy is defined as "the ability of the system to supply the aggregate electric power and energy requirements to the consumers at all times." Operating reliability is defined as "the ability of the system to withstand sudden disturbances such as electrical short circuits." The level of reliability is typically measured by the frequency, duration, and magnitude of the loss of service to total customers.
For Hawaiian Electric, the most recent top causes of outages are the following:
- "Vegetation," which includes downed trees, tree branches in power lines, and overgrown vegetation, some of which falls outside of the Company's scope of clearance
- "Equipment Deterioration," which is mainly attributed to breakdown from natural causes
- "Cable Faults," which are due to underground cable system failures
- “Automatic Underfrequency Load Shed,” which is controlled automatic load shedding to recover from underfrequency conditions
The following service reliability indices are commonly used in the electric power utility industry as a method of measuring system reliability performance. For the period prior to and including March 31, 2021, reliability indices were calculated using the Institute of Electrical and Electronics Engineers (IEEE) Standard 1366TM-2012 methodology.1 For the period April 1, 2021 and forward, reliability indices are calculated using an adjusted IEEE 1366 methodology.2 Consistent with utility practice across the country, reliability metrics shown below for SAIDI, SAIFI, CAIDI, and MAIFI are reported on a normalized basis and exclude Major Event Days (MEDs), those days in which the daily system SAIDI exceeds the MED threshold value (TMED). Statistically, days having a daily system SAIDI greater than TMED indicate days on which the energy delivery system experienced stresses beyond that normally expected (such as during severe weather). While it is important to measure reliability for all events, normalized data is more reflective of day-to-day reliability and generally provides a better indication of reliability and reliability trends.
For service reliability indices, current outage event data is used to calculate the indices. Outage event data for previously reported periods may change as new information becomes available.
1 In 2016, Hawaiian Electric adopted procedures established by IEEE Standard 1366‐2012. IEEE Standard 1366, “IEEE Guide for Electric Power Distribution Reliability Indices,” was developed to foster uniformity in the development of distribution service reliability indices and to provide tools for internal and external comparisons. In addition to providing definitions for key reliability indices, IEEE 1366 provides a consistent and objective method for identifying and removing MEDs for the purpose of studying reliability under normal daily operation.
2 Docket No. 2019-0110, Decision and Order No. 37600, issued on February 2, 2021. https://dms.puc.hawaii.gov/dms/DocumentViewer?pid=A1001001A21B02B15413D00151
System Average Interruption Duration Index
System Average Interruption Duration Index (SAIDI) measures the average length of time customers are without power during a predefined period of time. It is commonly measured in minutes or hours of interruption. SAIDI is one indication of overall system reliability because it incorporates the impact of frequency and duration of outages on the total customer base. View the calculation formula for SAIDI.
Hawaiian Electric
Oahu
Maui County
Hawaii Island
Please click the button below for historical normalized and non-normalized data (in Excel format).
System Average Interruption Frequency Index
System Average Interruption Frequency Index (SAIFI) measures the average frequency or number of times customers experience a sustained interruption of service during a predefined period of time. View the calculation formula for SAIFI.
Hawaiian Electric
Oahu
Maui County
Hawaii Island
Please click the button below for historical normalized and non-normalized data (in Excel format).
Customer Average Interruption Duration Index
Customer Average Interruption Duration Index (CAIDI) measures the average length of time an interrupted customer is without power during a predefined period of time. View the calculation formula for CAIDI.
Hawaiian Electric
Oahu
Maui County
Hawaii Island
Please click the button below for historical normalized and non-normalized data (in Excel format).
Momentary Average Interruption Frequency Index
Momentary Average Interruption Frequency Index (MAIFI) measures the average frequency or number of times customers experience a momentary interruption of service during a predefined period of time. Momentary interruptions have a duration of five minutes or less. View the calculation formula for MAIFI.
Hawaiian Electric
Oahu
Maui County
Hawaii Island
Please click the button below for historical normalized and non-normalized data (in Excel format).
Emergency Response Time
The emergency response time metric measures the average time it takes Hawaiian Electric to respond to an emergency event. Hawaiian Electric defines "emergency event" as an event involving the electric utility equipment that may pose an immediate threat to public safety or welfare. These events may include, but are not limited to: fire calls, dislodged manhole covers, energized lines down (sparking lines), downed poles, motor vehicle accidents involving utility equipment that result in lane closures or possible contact with energized utility lines.
This metric tracks (1) the start time when the utility has adequate and accurate information concerning the emergency event, (2) the average time it takes for the utility personnel to arrive onsite, and (3) the average time to safely and adequately secure the scene from any identified electrical hazard to the public, and to report back to Hawaiian Electric's operations centers after the scene has been secured. This metric will be tracked in minutes.
Hawaiian Electric did not previously track the minute intervals for the measures listed above. The Company began reporting this metric starting in the first quarter of 2015.
Hawaiian Electric
Oahu
Maui County
Hawaii Island
Please click the button below for historical normalized and non-normalized data (in Excel format).
