20230425Annual ISQ Program Report.pdf

Avista Corp. 1411 East Mission Ave., P.O. Box 3727 Spokane, WA 99220-0500
Telephone: [phone] Toll Free: 800-227-9187 April 25, 2023
Jan Noriyuki, Secretary Idaho Public Utilities Commission 11331 W. Chinden Blvd. Bldg. 8, Ste. 201-A
Boise, Idaho 83714 RE: Avista Utilities 2022 Idaho Service Quality (ISQ) Program Report Dear Ms. Noriyuki:
Attached for electronic filing is the 2022 Idaho Service Quality (ISQ) Program Report of
Avista Corporation, dba Avista Utilities (Avista or “the Company”), pursuant to the Company’s
electric tariff Schedule 85 and natural gas Schedule 185.
If you have any questions regarding this filing, please contact me at [phone] or
[e-mail].
Sincerely,
/s/ Jaime Majure
Jaime Majure Regulatory Policy Analyst Avista Utilities

Enclosure
RECEIVED
Tuesday, April 25, 2023 2:05:35 PM
IDAHO PUBLIC
UTILITIES COMMISSION

Avista Utilities
2022
Idaho Service Quality Program Report

Avista Utilities - 2022 Idaho Service Quality Program Report 1
Table of Contents
I. Introduction ................................................................................................................... 2 II. Executive Summary ...................................................................................................... 3
Customer Service Measures - Results for 2022 .................................................................. 3
Electric System Reliability - Results for 2022 .................................................................... 4 Customer Service Guarantees – Results for 2022............................................................... 6 III. Customer Service Measures .......................................................................................... 7 Measure 1: Customer Satisfaction with the Telephone Service provided by Avista’s Customer Service Representatives .............................................................. 8
Measure 2: Customer Satisfaction with Avista’s Field Service Representatives ...... 10
Measure 3: Answering Our Customers’ Calls Promptly ........................................... 11
Measure 4: Avista’s Response Time for Electric Emergencies ................................ 13
Measure 5: Avista’s Response Time for Natural Gas Emergencies ......................... 14
IV. Electric System Reliability ......................................................................................... 15
Measure 1: Number of Electric System Outages ...................................................... 17
Measure 2: Average Duration of Electric System Outages ....................................... 18
V. Customer Service Guarantees ..................................................................................... 19 Guarantee 1: Keeping Electric and Natural Gas Service Appointments ................... 19
Guarantee 2: Prompt Restoration of Electric System Outage ................................... 20
Guarantee 3: Promptly Turning on Electric or Natural Gas Service Upon Request.................................................................................................................................. 21
Guarantee 4: Promptly Providing Cost Estimates to Customers for New Service ... 22
Guarantee 5: Promptly Responding to Customers’ Bill Inquiries ............................. 22
Guarantee 6: Promptly Responding to Customers’ Meter Problems ........................ 24
Guarantee 7: Providing Customers Advance Notice of Scheduled Electric
Interruptions ............................................................................................................. 24
Appendix A – Service Quality Program Report Card ............................................... 26
Appendix B - Definitions and Index Calculations .................................................... 27

Avista Utilities - 2022 Idaho Service Quality Program Report 2
I. Introduction
On December 28, 2017, the Commission issued Order No. 33953 in the Company’s general rate case,1 approving the Settlement Stipulation filed by the Parties2 and
requiring the Company to make additional
compliance filings to meet the terms and conditions of the Settlement. With respect to Service Quality/Performance Measures, the Parties agreed that:

Avista has established Service Quality Performance, Customer Guarantees and a
Service Quality Measure Report Card for its customers in Washington. The Company and interested parties will work to develop similar performance standards, customer guarantees and a reporting mechanism for its Idaho
customers. Following those discussions, the Company will file its proposal with
the Commission requesting implementation on or before July 1, 2018. (Stipulation
and Settlement Para. 21) An initial draft of the proposed Idaho Service Quality (ISQ) Program (ISQ Program or
Program) was provided to Commission Staff (Staff) on February 15, 2018. Through the
course of subsequent discussions and collaborative efforts, Avista and Staff agreed on a set of service measures and accompanying benchmarks and reporting requirements that, taken together, provide an overall assessment of the quality of the Company’s service to its Idaho customers. Referred to collectively as Avista’s ISQ Program, and approved by the
Commission on November 1, 2018 with associated tariff Schedule 85 for electric service
and Schedule 185 for natural gas service, these measures include:
 Five (5) individual measures of the level of customer service and satisfaction that the Company must achieve each year;3
 Reporting on two (2) measures of electric system reliability;

 Seven (7) individual service standards through which Avista provides customers a payment or bill credit in the event the Company does not deliver the required
service level (Customer Service Guarantees). Under this agreement, the Company also reports to its customers and the Commission annually on its prior-year performance in meeting these customer service quality and reporting requirements. The following report includes a summary of the 2022 annual

1 Case Nos. AVU-E-17-01 and AVU-G-17-02 2 Stipulation “Parties” include Avista, IPUC Commission Staff, Clearwater Paper Corporation, Idaho Forest
Group, LLC, and the Community Action Partnership Association of Idaho (CAPAI). 3 Four individual Customer Service Measures exist within each of Avista’s approved tariff schedules; the fourth benchmark differs in its requirements between electric and natural gas service, resulting in five separate measures altogether.

Avista Utilities - 2022 Idaho Service Quality Program Report 3
results of its ISQ Program, followed by a more in-depth explanation of the measures themselves and associated annual outcomes.
II. Executive Summary
In compliance with Order No. 34181 in Case Nos. AVU-E-18-10 and AVU-G-18-06,
Avista’s 2022 ISQ Program Report (Report) provides the annual performance results for
the Company’s ISQ Program for 2022. This is the Company’s fifth year reporting information regarding Customer Service Measures and Electric System Reliability for its Idaho service territory, and its fourth year reporting on Customer Service Guarantees (Guarantees). Tracking of the Company’s performance on these Guarantees, including the
application of customer credits, began on January 1, 2019. During its 2022 Program year,
Avista is pleased to report that the Company has once again exceeded all five of its Customer Service Measures. The Company also celebrates a 100% success rate for a third year in row in restoring service within 24 hours of notification from customers after they have reported an electric outage, totaling 11,062 customers in 2022. Finally, Avista
successfully met 99.58% of its applicable Customer Service Guarantees in 2022, providing
customers a guarantee credit in 154 out of 36,534 cases. The overall success rate of these Guarantees shows Avista’s continued commitment to serving our customers.
Customer Service Measures - Results for 2022
Listed in Table No. 1 below are the five Customer Service Measures, including their respective service requirements (benchmarks), and the Company’s performance results in
meeting them for 2022. Avista achieved all of its customer service benchmarks for the year.
Table No. 1 – 2022 Results for Avista’s Customer Service Measures
Customer Service Measures Benchmark 2022 Performance Achieved
Percent of customers satisfied with our Contact
Center services, based on survey results At least 90% 97%

Percent of customers satisfied with field services, based on survey results At least 90% 97%

Percent of calls answered live within 60 seconds by our Contact Center At least 80% 81%

Average time from customer call to arrival of field technicians in response to electric system emergencies, per year
No more than
65 minutes 60 minutes

Average time from customer call to arrival of
field technicians in response to natural gas system emergencies, per year
No more than 55 minutes 40 minutes

Avista Utilities - 2022 Idaho Service Quality Program Report 4
Electric System Reliability - Results for 2022
Table Nos. 2 and 3 below list the two measures of electric system reliability to be reported by
Avista each year as part of its ISQ Program. Because the annual electric reliability results often vary substantially year-to-year (the case for any electric
utility’s system), it is difficult to derive a meaningful assessment of the Company’s system reliability from any single-year’s result. Consequently, in addition
to reporting the current-year result for each measure, Avista also reports the average value of each measure for the previous five year period, the average for the current five-year period (which includes the results for the current year - 2022), and the historic “five-year rolling average” from 2008 – 2022. This data provides some context for better interpreting each year’s reliability
results.
Table No. 2 – 2022 Results for Number of Outages on Avista’s System (SAIFI)
Number of Outages 2022 System Results
Current 5-Year Average (2018-2022)
Previous 5-Year Average (2017-2021)
Average number of sustained outages (interruptions) per customer for the year
(SAIFI)4
0.92 Per Customer 0.96 Per Customer 1.02 Per Customer
Table No. 3 – Results for Duration of Outages on Avista’s System in 2022 (SAIDI)
Outage Duration 2022 System Results
Current 5-Year Average (2018-2022)
Previous 5-Year Average (2017-2021)
Average duration of sustained outages (interruptions) per customer for the year. (SAIDI)5 146 Minutes 141 Minutes 148 Minutes

4 See Appendix B for a more detailed definition of these reliability measures and calculation of indices. 5 See Appendix B.

Avista Utilities - 2022 Idaho Service Quality Program Report 5
Figure Nos. 1 and 2 below show the “five-year rolling average”
for each reliability measure
from 2008 through 2022. As shown in the figures, the long-term trend for each reliability measure is fairly stable during
this period. The trend in number
of outages is slightly declining, while that for outage duration is variable but steady, showing an overall trend toward improved
system reliability. Though the
Company formally reports its reliability results for its entire electric system in its Washington Electric Service Reliability Report, provided annually to Idaho as a courtesy, Avista also agreed to track and report its Idaho-specific annual results as part of the ISQ Program. The Idaho-only number of
average electric system outages per customer in 2022 was 1.06, and the average total outage
duration per customer was 163.95 minutes; both figures constitute a decrease from the 1.51 outages per customer and 221.73 duration reported for 2021.
Figure No. 1 – Historic Five-Year Rolling Average for Number of Electric Outages on Avista’s Electric System (SAIFI)

1.27 1.20 1.12 1.09 1.04 1.05 1.01 0.97 0.94 1.02 0.96
0
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0.8
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1.2
1.4
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Historic Five-Year Averages of the Annual Number of
Outages
(SAIFI)

Avista Utilities - 2022 Idaho Service Quality Program Report 6
Figure No. 2 – Historic Five-Year Rolling Average for Duration of Outages on Avista’s Electric System (SAIDI)

Customer Service Guarantees – Results for 2022
Our ISQ Program includes seven types of service for which we provide Customer Service Guarantees. In the event that the
Company fails to meet a Customer Service
Guarantee, Avista provides the customer or applicant a bill credit or payment in the amount of $50 in recognition of the inconvenience. All costs associated with the
payment of Customer Service Guarantees are
paid by the Company’s shareholders and are not paid by our customers in their rates for service or otherwise. Table No. 4 below provides a list of the services covered in the
ISQ Program Guarantees, as well as the
Company’s performance results in meeting these Guarantees in 2022.
151 147
136 139 142
151 149 151
142 148 141
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20
40
60
80
100
120
140
160
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Historic Five-Year Averages of Annual Outage Duration
(SAIDI)

Avista Utilities - 2022 Idaho Service Quality Program Report 7
Table No. 4 – 2022 Results for Avista’s Customer Service Guarantees
Customer Service Guarantee Successful Missed $ Paid
Keeping Our Electric and Natural Gas Service
Appointments scheduled with our customers 1,510 7 $350
11,062 0 $0
Turn on power the same day the request is received 3,427 1 $50
Provide a cost estimate for new electric or natural gas service within 10 business days of receiving the request 1,333 0 $0
Investigate and respond to a billing inquiry within 10 business days if unable to answer a question on first contact 498 0 $0
Investigate a reported meter problem or conduct a meter test and report the results within 20 business days 255 1 $50
Notify customers at least 24 hours in advance of a planned power outage lasting longer than 5 minutes 18,295 145 $7,250
Totals 36,380 154 $7,700

III. Customer Service Measures
There are many points of service customers may have with Avista, and each contributes to the overall impression of the Company and the level of satisfaction associated with our
services. While Avista has tracked its customers’ satisfaction with primary services such
as customer contact center and field services for many years, the Company has also been interested in knowing whether its performance is meeting customers’ broader service expectations. To accommodate this interest, Avista’s Voice of the Customer (VOC) survey asks customers to rate their level of satisfaction with the overall service they receive from
the Company. This overall measure is believed to be an important barometer of our
customers’ satisfaction with the entirety of the integrated services and value they receive from Avista. As show in Figure No. 3 below, the overall satisfaction of Avista’s customers (either satisfied or very satisfied) has ranged between 93% and 97% over the past ten years.

Avista Utilities - 2022 Idaho Service Quality Program Report 8
Figure No. 3 – Percent of Customers Satisfied or Very Satisfied with Avista’s Overall Service Level 2012-2022

These results are similar to our customers’ satisfaction with our contact center and field services, as reported for the ISQ Program for this same time period. Accordingly, we believe the results of the five Customer Service Measures described in the following sections, taken together, provide a reasonable assessment of our customers’ overall
satisfaction with the quality and value of our service.

Measure 1: Customer Satisfaction with the Telephone Service provided by Avista’s Customer Service Representatives
As part of Avista’s Idaho Service Quality program, the level of our customers’ satisfaction with the telephone service provided by the
Company’s contact center will meet or exceed a benchmark of 90%.6

6 The level of Customer satisfaction with telephone service, as provided by the Company’s Contact Center, will be at least 90 percent, where: a. The measure of Customer satisfaction is based on Customers who respond to Avista’s quarterly survey of Customer satisfaction, known as the “Voice of the Customer”, as conducted by its independent survey contractor;
93
95 95 96
94 95 97
94
96 96 97
70
80
90
100
2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022
Percent of Customers Satisfied or Very Satisfied
with Avista's Overall Service 2012-2022

Avista Utilities - 2022 Idaho Service Quality Program Report 9
Several factors influence our customers’ satisfaction with the quality of telephone service provided by our Customer Service Representatives (CSRs) and contact center. We measure
the importance of these factors to customers as well as their satisfaction with them each
year. These factors, including our customers’ satisfaction (either satisfied or very satisfied) for each factor in 2022 are listed below.
 The CSR handling the customer’s call in a friendly, caring manner. (98%)
 The CSR being informed and knowledgeable. (97%)
 The CSR meeting the customer’s needs promptly. (96%)
 The CSR giving the customer all the information they need in one call. (95%)
 Being connected to a CSR in a reasonable amount of time. (95%)
2022 Results – The annual survey results for this measure of customer satisfaction show
that, overall, 97% percent of Avista’s customers were satisfied with the quality of the telephone service they received from our Customer Service Representatives.
Table No. 5 – Customer Satisfaction with Avista’s Contact Center Representatives in 2022
Customer Satisfaction with Avista’s Contact Center Representatives Service Quality 2022 Performance Achieved
Percent of customers either satisfied or very satisfied with the Quality of Avista’s
Customer Contact Center Representatives
90% or Greater
Satisfied
97%

For the purposes of reporting our annual service quality performance under this Program, the Company will continue to use its system-wide results. Avista will also separately track and report the results for this measure for our Idaho customers only, though it is not a
requirement of the ISQ Program. For 2022, the percent of Idaho customers satisfied or
very satisfied with the Company’s CSRs and contact center was 97%, with 90% of our customers noting they were “very satisfied” and 7% noting they were “satisfied”. 7 While only a slight increase from the overall 95% satisfaction rate reported in 2021, there was a marked increase in the percentage of customers noting “very satisfied”, from 84% to 90%
(thereby resulting in a decrease for “satisfied”, from 11% to 7%).

b. The measure of satisfaction is based on Customers participating in the survey who report the level of their satisfaction as either “satisfied” or “very satisfied”; and c. The measure of satisfaction is based on the statistically-significant survey results for both electric and natural gas service for Avista’s entire service territory (Idaho, Oregon, and Washington) for the calendar year. 7 The Customer Satisfaction Results have been rounded.
a. Total percent of customers either satisfied or very satisfied with the Quality of Avista’s Customer Contact Center Representatives is actually 97%. b. Percent of customers very satisfied with the Quality of Avista’s Customer Contact Center Representatives is actually 90%. c. Percent of customers satisfied with the Quality of Avista’s Customer Contact Center Representatives is actually 7%.

Avista Utilities - 2022 Idaho Service Quality Program Report 10

Measure 2: Customer Satisfaction with Avista’s Field Service Representatives
As part of Avista’s Service Quality Measures program, the level of our
customers’ satisfaction with the Company’s field services will meet or
exceed a benchmark of 90%.8
The quality of our field services and the satisfaction of our customers is influenced by several factors. Each year we measure the importance of these factors to our customers and their satisfaction with each aspect of our service. These factors, including our customers’
level of satisfaction (either satisfied or very satisfied) with each factor in 2021, are listed
below.
 The service representative keeping you informed of the status of your job. (94%)
 The service representative or service crew being courteous and respectful.
(99%)
 The service representative or service crew being informed and knowledgeable. (99%)
 The service representative or service crew leaving your property in the condition they found it. (98%)
 The service work being completed according to the customer’s
expectations. (98%)
 The overall quality of the work performed by Avista Utilities. (98%)
2022 Results – The annual survey results for this measure, as reported in Table No. 6 below, show that 97% percent of our customers were satisfied with the service provided
by Avista’s field service representatives.

8 The level of Customer satisfaction with the Company’s field services will be at least 90 percent, where:
d. The measure of Customer satisfaction is based on Customers who respond to Avista’s quarterly survey of Customer satisfaction, known as the ”Voice of the Customer”, as conducted by its independent survey contractor; e. The measure of satisfaction is based on Customers participating in the survey who report the level of their satisfaction as either “satisfied” or “very satisfied”; and f. The measure of satisfaction is based on the statistically-significant survey results for both electric and natural gas service for Avista’s entire service territory (Idaho, Oregon, and Washington) for the calendar year.

Avista Utilities - 2022 Idaho Service Quality Program Report 11
Table No. 6 – Customer Satisfaction with Avista’s Field Services Representatives in 2022
Customer Satisfaction with Avista’s Field Services Representatives Service Quality 2022 Performance Achieved
Percent of customers either satisfied or very
satisfied with the Quality of Avista’s Field Service Representatives
90% or
Greater Satisfied 97%

As with its contact center customer satisfaction, Avista will continue to use its system-wide results for the purposes of reporting our annual service quality performance under this program. The Company will also separately track and report the results for this measure for our Idaho customers only, although it is not a requirement of the ISQ Program.
For 2022, the percent of Idaho customers satisfied or very satisfied with the Company’s field service representatives was slightly higher than the system-wide results at 98%, with 92% of customers “very satisfied” and 6% “satisfied” with the quality of our field services. As with its contact center customer satisfaction results, the percentage of customers noting “very satisfied” increased notably, to 92% from 2021’s 88% (with “satisfied” then
decreasing from 10% to 6%).

Measure 3: Answering Our Customers’ Calls Promptly
As part of Avista’s Service Quality Measures program, the percentage of customer calls answered live by a customer service representative within
60 seconds will average 80% or greater.9
This particular customer service measure is one of the subsets of service attributes that contribute to the customer’s overall satisfaction with our CSRs and contact center. Often referred to as the “Grade of Service” or “GOS”, this measure is the average percentage of customer calls to our contact center that are answered live by a CSR within 60 seconds for
those customers who wish to speak with a Customer Service Representative. When a customer calls Avista’s contact center, their call is initially received by our automated

9 The percentage of Customer calls answered by a live representative within 60 seconds will average at least 80 percent for the calendar year, where: a. The measure of response time is based on results from the Company’s Contact Center, and is initiated when the Customer requests to speak to a Customer service representative; and b. Response time is based on the combined results for both electric and natural gas Customers for Avista’s entire service territory (Idaho, Oregon, and Washington).

Avista Utilities - 2022 Idaho Service Quality Program Report 12
(voice activated) phone system. The customer is presented the option of using the phone system for self-service (e.g. to check their account balance or pay their bill, etc.) or to speak
with a CSR live to meet their service need. Avista’s response time in answering the
customer’s call is the time that elapses between the customer’s request to speak to a representative and when their call is answered live by a representative.
For many years Avista has maintained a service benchmark of 80% or greater, even though some utilities and businesses have established a higher GOS (e.g. 90% or a goal of
answering calls within 30 seconds). Because it requires an increased level of staffing and
cost to customers to achieve a higher service level, Avista has focused on lower cost/no cost measures, such as effective employee training and coaching to achieve superior standards for attributes such as courtesy, caring, knowledge, and proficiency, to maintain our very-high level of overall customer satisfaction with our Customer Service
Representatives and contact center.
In addition to responding to customers effectively, Avista has implemented measures to help reduce the overall volume of customer calls, which helps reduce the cost of service paid by our customers. These efforts include providing customers a way to communicate with the Company using their preferred “channel” of communication, such as e-mail,
online chat, customer self-service via website, or the automated phone system. In addition
to providing numerous communication channels, the Company has focused on enhancing customer self-service options as discussed above. These efforts not only help reduce the volume of calls to our contact center and maintain a high level of service at lower cost, but also improve customer experience and satisfaction.
2022 Results – Avista’s customers made a total of 494,531 qualifying calls to the Company
that were answered live by a Customer Service Representative in 2022. Of these calls, 398,500 were answered live in 60 seconds or less, for a GOS of approximately 81%, as shown in Table No. 7 below.
Table No. 7 – Percent of Avista’s Customer Calls Answered Live within 60 Seconds in 2022
Percent of Avista’s Customer Calls Answered Live Within 60 Seconds Service Quality 2022 Performance Achieved
Percent of Avista’s customer calls answered live by a Customer Service Representative within 60 seconds
80% or Greater 81%

Avista Utilities - 2022 Idaho Service Quality Program Report 13

Measure 4: Avista’s Response Time for Electric Emergencies
As part of Avista’s Service Quality Measures program, the average
response time to an electric system emergency will not exceed 65 minutes
for the year.10 When customers call Avista to report an electric emergency, the Company works with the customer to quickly ascertain the particular circumstances being reported and instructs the
customer on how best to ensure the safety of themselves and that of others until help
arrives. We immediately begin the dispatch of service personnel best situated to respond in the shortest time possible. Once at the scene, Avista’s first priority is to make the situation safe for our customers, citizens, other emergency responders, and our employees. Restoration of the problem can begin once the safety of the site is secured and needed
resources arrive at the scene. The Company’s ability to respond quickly to an electrical
emergency is influenced by many factors, some of which include the urban or rural locale, the location of the nearest available respondent (especially in rural areas), the time of day, season of the year, weather conditions, traffic, and the presence of other simultaneous emergency events across the system. For this measure, the response time to an electric
emergency is the elapsed time between the confirmation of the emergency with the
customer (when the dispatch field order is given) and when the Avista service person arrives at the scene.
2022 Results – The average response time for the year is calculated by dividing the sum of all applicable electric emergency response times by the total number of qualifying
electric emergency incidents. Avista received 245 qualifying electric emergency reports in
its Idaho service area in 2022, which had a cumulative response time of approximately 14,785 minutes. The resulting average for 2022 was 60 minutes, as noted in Table No. 8 below.
10 The Company’s average response time to an electric system emergency in Idaho will not exceed 65 minutes for the calendar year, where: a. Response time is measured from the time of the Customer call to the arrival of a field service technician;
b. Response times are excluded from the calculation for those periods of time when the Company is experiencing an outage that qualifies as a Major Event Day (MED) in Idaho, as defined by the Institute of Electrical and Electronics Engineers, Inc. (IEEE) Guide for Electric Power Distribution Reliability Indices, Standard 1366. This includes the 24 hour period following a Major Event Day. c. An “electric system emergency” is defined as an event involving police/fire departments, arcing/flashing wires down, or a feeder lockout.

Avista Utilities - 2022 Idaho Service Quality Program Report 14
Table No. 8 – Avista’s Response Time for Electric Emergencies in 2022
Avista’s Response Time for Electric Emergencies Service Quality 2022 Performance Achieved
Average time from customer call to the arrival of Avista’s field technicians in response to electric system emergencies
65 Minutes or Less 60 Minutes

Measure 5: Avista’s Response Time for Natural Gas Emergencies
As part of Avista’s Service Quality Measures program, the average
response time to a natural gas system emergency will not exceed 55
minutes for the year.11 When customers call Avista to report a natural gas emergency, the Company works with the customer to quickly ascertain whether the presence of natural gas (via odor or some
other characteristic) is likely coming from inside the customer’s home or business or from
facilities located outside. If inside, the customer is instructed to immediately evacuate the building to a safe distance and await the arrival of emergency responders. If the leak is in facilities outside, instructions to the customer are based on the proximity and type of the leak to their (or others’) home or business. Once the nature of the issue has been determined
and the customer has been given precautionary instructions on how best to ensure their
own safety and that of others until help arrives, the Company immediately begins to dispatch the service personnel best situated to respond at the scene in the shortest time possible. At the scene, Avista’s first priority is to make the situation safe for our customers, citizens, other emergency responders, and our employees. Restoration of the problem can
begin once the safety of the site is secured and needed resources arrive at the scene.
The Company’s ability to respond quickly to a natural gas emergency is influenced by many factors, some of which include the urban or rural locale, the location of the nearest available respondent (especially in rural areas), the time of day, season of the year, weather

11 The Company’s average response time to a natural gas system emergency in Idaho will not exceed 55 minutes for the calendar year, where: a. Response time is measured from the time of the customer call to the arrival of a field service technician; and b. A “natural gas system emergency” is defined as an event involving a natural gas explosion or fire, a fire in the vicinity of natural gas facilities, police/fire departments, leaks identified in the field as “Grade 1”, high or low gas pressure problems identified by alarms or customer calls, natural gas system emergency alarms, or calls regarding carbon monoxide, natural gas odor, runaway furnace, or delayed ignition.

Avista Utilities - 2022 Idaho Service Quality Program Report 15
conditions, traffic, and the presence of other simultaneous emergency events across the system. Natural gas emergencies differ from electric emergencies, however, in that the risk
of a potential consequence to a natural gas leak can increase with the passage of time as
leaking natural gas may accumulate at the site. For this reason, Avista’s work practices and staffing levels aim to provide an average response time of 55 minutes or less. For this measure, the response time to a natural gas emergency is the elapsed time between the confirmation of the emergency with the customer (when the dispatch field order is given)
and when the Avista service person arrives at the scene.
2022 Results – The average response time for the year is calculated by dividing the sum of all applicable natural gas emergency response times by the total number of qualifying emergency incidents. Avista received 2,171 qualifying natural gas emergency reports in its Idaho service area in 2022, which had a cumulative response time of 85,889 minutes. The
resulting average for 2022 was 40 minutes as noted in Table No. 9 below.

Table No. 9 – Avista’s Response Time for Natural Gas Emergencies in 2022
Avista’s Response Time for Natural Gas Emergencies Service Quality 2022 Performance Achieved
Average time from customer call to the arrival of Avista’s field technicians in response to natural gas system emergencies
55 Minutes or Less 40 Minutes

IV. Electric System Reliability
Providing safe and highly-reliable electric service for our customers at a reasonable cost is fundamental to our business. We believe our current level of reliability is reasonable,
acceptable and cost effective for our customers, and our long-term objective is to generally
uphold our current levels of electric system reliability. Achieving this requires an ongoing effort to balance the many investments and other priority needs across our system for today and with implications that project far into the future. As already explained, we monitor and track various aspects of the reliability performance of our system each year, relying on
industry-standard measures (or indices). Two of the most-commonly reported measures are
very-briefly described below, and are discussed in greater detail in Appendix B. For its Idaho Service Quality Program, Avista reports its annual reliability results in the context of its historic five-year rolling average for these two measures:
 Number of Outages – known technically as the System Average Interruption
Frequency Index or “SAIFI,” is the average number of sustained interruptions
(outages) per customer for the year.
 Outage Duration – known technically as the System Average Interruption Duration Index or “SAIDI,” is the average duration of sustained interruptions (outages) per customer for the year.
Many factors influence the number and duration of outages on any electric system. Some
of these include the average age of the system, its engineering design, construction

Avista Utilities - 2022 Idaho Service Quality Program Report 16
standards, general condition, the extent of the system that is rural, terrain, utility equipment and staffing levels, and its day-to-day operation. The type and proximity of surrounding
vegetation and local and regional weather patterns, including variability in weather, can
have a pronounced impact on system reliability. Because the frequency and duration of the electric system outages that result from these factors can vary substantially from year to year, there is, naturally, a lot of variability in the annual measures of system reliability over time.
For Avista, weather-related outages tend to have a predominant impact on the reliability of
our system. This is because individual weather events often impact large portions of our system and can result in damage to many types of facilities. Weather caused outages, particularly from high winds, ice, and snow can also require substantial effort and time to restore. These storm events can result in many customers without service for an extended
period of time. Because the impact of weather events on system reliability is common to
all electric systems, the industry has adopted standardized adjustments that remove outages related to weather events of a certain magnitude from the calculation of results for outage frequency and duration. This threshold level of severity is referred to as a Major Event Day or (“MED”). The outages caused by any storm event that qualifies as a MED are removed
from the data used to calculate the utility’s annual reliability results. For Avista, the impact
of these major storm events is clearly evident in the substantial system outages caused by windstorms in the late summer of 2014, and the very significant windstorm event of November 2015. By contrast, in 2016, the Company did not experience any storm events that constituted major event days, and since that time have experienced a fairly-limited
number of major events each year, including 2022. Although the year-to-year variability
in outage duration is substantially reduced by the adjustment for major events, there can still be a substantial weather impact on the reliability results we report each year. This is the result of storms that, while not qualifying as major events, still result in substantial system outages.
The important point of this discussion is that the reliability results for any single year,
considered in isolation, do not provide a meaningful measure of the overall reliability of the utility’s system, or an assessment of whether the performance that year was “acceptable” or “unacceptable”. The reliability performance of our system (or any utility system) should be evaluated over the long term as the basis for evaluating whether our
reliability is trending stably, improving, or degrading.12 Avista has agreed to report its
annual reliability results to its customers in the context of its historic five-year rolling average. This approach helps our customers better understand how each year’s reliability results fit into our long-term trend in overall system reliability.

12 This is similar to the approach now used by the California Public Utilities Commission to evaluate electric utilities’ system reliability. In: Approaches to Setting Electric Distribution Reliability Standards and Outcomes, pages 130 - 136. The Brattle Group, Ltd. 2012.

Avista Utilities - 2022 Idaho Service Quality Program Report 17

Measure 1: Number of Electric System Outages
As part of Avista’s Service Quality Measures program, the Company will report
its annual electric system reliability measure for the number of non-major storm
power outages experienced per customer for the year (SAIFI).13 2022 Results – This measure, as noted earlier, represents how often on average an Avista electric customer experienced a sustained14 service outage during the year. This measure
is calculated by summing the total number of customer outages recorded for the year,
divided by the total number of customers served by the Company in that year. The 2022 result of 0.92 outages per customer is below the average value for the previous five-year period (2017-2021) of 1.02, as well as for the current five-year period (2018-2022) of 0.96. For 2022, our Idaho-only result was 1.06 outages per customer.

Table No. 10 – Number of Electric System Outages for the Average Avista Customer in
2022
Number of Electric System Outages for the Average Avista System 5 Year Average 5 Year
Number of sustained interruptions in electric service for the average Avista
customer for the year (SAIFI)
0.92 Per Customer 0.96 Per Customer -0.06 Per Customer

13 The Company will report the frequency of electric system interruptions per Customer for the calendar year, where: a. The interruptions are measured as the System Average Interruption Frequency Index (“SAIFI”), as calculated by IEEE Std. 1366; b. The calculation of SAIFI excludes interruptions associated with any MED in Idaho; c. The report will provide a brief description of the predominant factors influencing the current-year results, the previous year’s system results, and the Company’s historic five-year rolling average of SAIFI; and d. The results will be reported on a system basis for Washington and Idaho as well as for Idaho only. 14 Any service interruption that is greater than five minutes in duration.

Avista Utilities - 2022 Idaho Service Quality Program Report 18

Measure 2: Average Duration of Electric System Outages
As part of Avista’s Service Quality Measures program, the Company will
report its annual electric system reliability measure for the total duration
of non-major storm power outages experienced per customer for the year (SAIDI).15 2022 Results – This measure, as noted earlier, represents the average duration or length of
outages for the year. Outage duration (SAIDI) is calculated by summing all of the customer
outage time occurring in the year, divided by the total number of customers served by the utility in that year. On a system-wide basis, the 2022 outage duration decreased to 146 minutes, 18 minutes lower than the 164-minute duration reported for 2021. As shown in Table No. 12 below, the current five-year average resulted in a 7-minute decrease to the
average for the current five-year period (2018-2022). The Idaho-only outage duration was
163.95 minutes for 2022, a decrease from 221.73 minutes for 2021; while higher than the system average, Avista continues to focus on improving infrastructure to increase the reliability of electric service, in addition to responding to unplanned outages as quickly and safely as possible.
Table No. 11 – Outage Duration for the Average Avista Customer in 2022
Total Outage Duration for the Average Avista Customer System 5 Year Average 5 Year
Total duration of all electric service outages for the average Avista customer for the year (SAIDI)
146 Minutes 141 Minutes -7 Minutes

15 The Company will report the duration of electric system interruptions per Customer for the calendar year, where:
a. The interruption duration is measured as the System Average Interruption Duration Index (“SAIDI”), as defined by the IEEE Std. 1366; b. The calculation of SAIDI excludes interruptions associated with any MED in Idaho; c. The report will provide a brief description of the predominant factors influencing the current-year system results, the previous year’s system results, and the Company’s historic five-year rolling average of SAIDI; d. The results will be reported on a system basis for Washington and Idaho as well as for Idaho only.

Avista Utilities - 2022 Idaho Service Quality Program Report 19

V. Customer Service Guarantees
Avista’s Idaho Service Quality Program includes seven types of service for which Avista provides “Customer Service Guarantees”. Our service commitments under these Guarantees recognize the customer inconvenience that may result when our delivered
service does not meet our stated goal. In such cases, we will provide our customers a bill
credit or payment in the amount of $50 in recognition of that inconvenience. All costs associated with the payment of these Guarantees are paid by the Avista’s shareholders, and are not paid by our customers, or included in the rates they pay for service. This 2022 Idaho Service Quality Report is the second Report to contain the results of Avista’s Guarantees.

Guarantee 1: Keeping Electric and Natural Gas Service Appointments
The Company will keep mutually agreed upon appointments for electric
or natural gas service, scheduled in the time windows of either 8:00 a.m.
– 12:00 p.m. or 12:00 p.m. – 5:00 p.m.16
Avista provides its customers with appointments for certain types of electric and natural gas service requests. For electric service, the Company will schedule appointments for service drops or disconnects. For all other electric service work, the customer does not
need to be present for the Company to perform the required work (i.e., check meter, meter test, voltage check, etc.). For natural gas service, the Company provides appointments for dealer-requested service, meter exchange and tests, meter unlock, no-heat inspections, reconnects, relighting of Avista repairs, and repeated pilot light outages on natural gas appliances. Avista offers more types of natural gas service appointments (than electric
service) because the customer must be present for our employees to complete the work as

16 Except in the following instances: a. When the Customer or Applicant cancels the appointment;
b. The Customer or Applicant fails to keep the appointment; or c. The Company reschedules the appointment with at least 24 hours’ notice; or d. The Company is experiencing an MED in Idaho. In such cases, the Company will notify the customer and reschedule the appointment. (electric service only)
of this program, providing our customers a guarantee credit in just 154 out of 36,534 cases.

Avista Utilities - 2022 Idaho Service Quality Program Report 20
they must enter the customer’s home. If the requested date and/or time of the service request is unavailable, the Company will still do its best to accommodate the customer’s
request, but will not commit to a specific time that an employee will arrive to work on the
service request. Often times this practice results in better customer satisfaction as the Company makes every effort to accommodate a customer’s request on that day, rather than schedule the work on a future date. Finally, new service connections and credit reconnects are not available for appointments, as the work orders are completed the same day of the
request.
2022 Results – In 2022, the Company successfully kept 99.54% of its 1,517 scheduled customer appointments for applicable electric and natural gas service in Idaho, and paid a guarantee credit in only seven instances for the year. The primary reason for missed appointments is emergency work orders that arise during the day, which prevent the
Company from meeting its scheduled appointment time. Due to the risks and danger of
electric and natural gas emergencies, the Company prioritizes emergency orders over all service work. The result of this necessary prioritization is that the Company will occasionally miss a few appointments.
Table No. 12 – Avista Service Appointment Results for 2022
Customer Service Guarantee Successful Missed $ Paid
Keeping Our Electric and Natural Gas Service Appointments scheduled with our
customers
1,510 7 $350
Guarantee 2: Prompt Restoration of Electric System Outage
When our Customers experience an electric interruption, the Company will restore the service within 24 hours of notification from the Customer.17
The Company strives to restore power to its customers as quickly as possible, while
maintaining the safety of our employees, customers, and the public as our top priority. Electric system outages can be complex and occur all hours of the day and night, and all days of the year. In many years, even in cases where Avista does not experience any storms that qualify as major events, it may still be impossible for us to restore service to all of our
customers within 24 hours. In other years, by contrast, the Company is able to successfully
restore service to all of our customers who experience an outage within this benchmark of 24 hours. For the 2022 Program year, Avista did not provide any guarantee credits to

17 Except for the following instances: a. During periods of time when the outage is associated with an MED in Idaho;
b. An action or event that is outside the control of the Company prevented the Company from restoring supply or accessing the Company’s equipment to restore supply; c. The premise is vacant, disconnected or not receiving service immediately preceding the outage; or d. The customer notifies the Company that service restoration does not require immediate attention.

Avista Utilities - 2022 Idaho Service Quality Program Report 21
customers, as we successfully restored service to all impacted customers within the benchmark timeframe.
2022 Results – In 2022, the Company’s Idaho customers experienced 11,062 outage events
in total, all of which had power restored within 24 hours, resulting in a success rate of 100%. The success rate for 2022 mirrors the success rate for 2020 and 2021 where Avista accomplished restoring service to all impacted customers within the 24-hour timeframe. In comparison to 2019’s 99.99% success rate, resulting from 1 of 18,774 outage events
missing the 24 hour benchmark, Avista is proud to see that the Company was able to
maintain its success rate from 2020-2022 in restoring power to its customers within 24 hours. Table No. 13 – Avista’s Outage Restoration Results for 2022
Customer Service Guarantee Successful Missed $ Paid
Restore service within 24 hours of a customer reporting an outage (excluding
major storm events)
11,062 0 $0
Guarantee 3: Promptly Turning on Electric or Natural Gas Service Upon Request
The Company will turn on power or connect natural gas service the same day the Customer or Applicant’s requests service.18
When customers request electric or natural gas service from Avista, they have a reasonable
expectation their service will be turned on as quickly as possible, or promptly on a future
date they request. The Company strives to meet these customer expectations by all reasonable means. Typically, the electric or natural gas meter is not shut off between customers, so when a customer moves to a new location the service is already on when they open an account for service at the new address. In situations where the service is not
already on at a customer location, the Company must send an employee to reconnect the
meter.

18 Except for the following instances: a. The service request is received by the Company after 7:00pm on weekdays, or on a weekend or holiday;
b. The Customer requests an alternative future date for service connection; c. The Customer or Applicant is not available at the time of connection (natural gas service only)
d. Construction is required before the service can be energized or connected; e. The Customer or Applicant does not provide evidence that all required government inspections have been satisfied; f. Required payments to the Company have not been received;
g. The service was disconnected for nonpayment or theft/diversion of service; h. The service cannot be turned on due to an outage;
i. Electric Service is not connected prior to connecting natural gas service; j. When applicable, water service is not connected prior to connecting natural gas service; or
k. An action or event that is outside the control of the Company prevents the Company from connecting service.

Avista Utilities - 2022 Idaho Service Quality Program Report 22
2022 Results – Avista met its benchmark to turn on our customers’ service the same day
the service was requested in 99.97% of cases, missing only one of the 3,427 requests
received.
Table No. 14 – Avista Turning on Service the Same Day for 2022
Customer Service Guarantee Successful Missed $ Paid
Turn on power within a business day of receiving the request 3,427 1 $50
Guarantee 4: Promptly Providing Cost Estimates to Customers for New Service
The Company will provide a cost estimate to the Customer or Applicant
for new electric or natural gas supply within 10 business days upon receipt
of all the necessary information from the Customer or Applicant.
When constructing a new home the process for providing new electric or natural gas supply can be complex, and may involve a customer, contractor, electrician, or dealer depending on the nature of the new service. A request for new electric or natural gas service is
typically routed through our customer contact center and is assigned to one of our employee Customer Project Coordinators (CPCs) in our natural gas or electric construction areas. Our CPCs are responsible for discussing the request with the customer (Applicant), meeting with the customer at the location, designing the service, and then providing the customer a cost estimate for the required construction. The Company’s goal for completing
the cost estimate, for which it offers a Customer Service Guarantee, is 10 business days.
2022 Results – The Company received 1,333 requests for new electric or natural gas service in 2022 and successfully provided cost estimates for each within 10 business days of the request, for a success rate of 100%. This continues the 100% success rate for a fourth year in a row (since the ISQ Program’s inception in 2019).
Table No. 15 – Avista Providing Customers a Cost Estimate for New Service in 2022
Customer Service Guarantee Successful Missed $ Paid
Provide a cost estimate for new electric or natural gas service within 10 business days of receiving the request 1,333 0 $0
Guarantee 5: Promptly Responding to Customers’ Bill Inquiries
The Company will respond to most billing inquiries at the time of the initial contact, and for those inquires that require further investigation,
the company will investigate and respond to the Customer within 10
business days.

Avista Utilities - 2022 Idaho Service Quality Program Report 23
For a customer, it can be difficult to understand why the amount of their energy bill can vary sometimes substantially from month to month. Some of these factors include
variability in weather, changes in rates, the result of an estimated bill amount in certain
circumstances, and variation in the number of billing days included in the billing period. When customers have questions about their bill, Avista’s CSRs strive to address and resolve all inquiries on the initial customer contact. Some of the tools our employees have to address such bill inquires (which are generally related to circumstances when customers
feel their bill is too high), include:
 Review the meter read and usage history to see if the bill is in line with the prior months or years;
 Review the number of billing days for the bill in question;
 Utilize the Company’s bill analyzer tool, which is also available to customers on
Avista’s website, for a comparison of weather, average usage, and rates;
 Discuss with the customer any life changes, new appliances, or maintenance needs and how those can impact their utility bill;
 Offer tips on ways to save energy;
 Direct the customer to Avista’s website for additional energy savings advice; and,
 Offer to mail Energy Use and Savings Guides or Energy Savings kits.
When the CSR is unable to address the billing inquiry on initial contact or the customer is not satisfied with the information provided on their inquiry, the Company will then open a case to further investigate the customer’s inquiry. After a case has been created Avista will verify the meter read or obtain a new meter read to double-check the accuracy of the
metered use. If there was a billing error the CSR will initiate sending a corrected bill. After
determining the accuracy of the bill, the Customer Service Representative will then discuss the inquiry again with the customer along with the results of the verification of the meter read or new meter read. Typically, after this process our customer is satisfied with the resolution. In situations where the customer is not satisfied and/or requests a meter test to
ensure their meter is reading accurately, it triggers a separate process, which is covered by
Customer Service Guarantee number six below, “Promptly Responding to Customers’ Meter Problems.”
2022 Results – Of the billing inquires that were not resolved upon the initial customer contact, the Company successfully investigated and responded within 10 business days to
all of the 498 follow-up inquiries received in 2022.

Table No. 16 – Avista Responding to Customer’s Bill Inquiries in 2022
Customer Service Guarantee Successful Missed $ Paid
Investigate and respond to a billing inquiry within 10 business days if unable to answer a question on first contact 498 0 $0

Avista Utilities - 2022 Idaho Service Quality Program Report 24
Guarantee 6: Promptly Responding to Customers’ Meter Problems
The Company will investigate Customer-reported problems with a meter,
or conduct a meter test, and report the results to the Customer within 20
business days.
Commission rules, concurrently with Avista’s tariff Schedule 170 for natural gas service, govern the utility’s requirement for meter testing. Avista has naturally complied with these requirements prior to the implementation of its Customer Service Guarantees program.
Under the Guarantees now in place, however, the Company will now provide a $50 credit
if it fails to meet this requirement.
2022 Results – In 2022, 256 of our Idaho customers reported a meter problem or requested the Company conduct a meter test. Avista successfully tested and reported the results to all but one of these customers within 20 business days, for a success rate of 99.61%.
Table No. 17 – Avista Resolving Meter Problems in 2022
Customer Service Guarantee Successful Missed $ Paid
Investigate a reported meter problem or conduct a meter test and report the results within 20 business days 255 1 $50

Guarantee 7: Providing Customers Advance Notice of Scheduled Electric Interruptions
The Company will provide notification to the Customer, through means
normally used by the Company, at least 24 hours in advance of disconnecting service for scheduled interruptions.19
Under Avista’s Customer Service Guarantees program, the Company will provide a $50 credit for each customer impacted if the Company fails to provide notice of a scheduled
interruption at least 24 hours in advance. Complying with this notification requirement has
always been a complex process because there are so many areas within the Company involved in the effort. Some of these include natural gas construction, electric operations, customer project coordinators, asset maintenance program managers, distribution dispatch, service dispatch, and the customer contact center. This complexity requires the Company
to maintain multiple checkpoints in our business processes to ensure all customers affected
by a scheduled interruption are notified in advance.
2022 Results – A total of 18,440 Idaho customers were affected by scheduled service interruptions in 2022. Of that total, Avista successfully notified 18,295 customers for a success rate of 99.21%. For the 145 customers that did not appropriately receive our

19 Except for the following instances:
a. The interruption is a momentary interruption of less than five minutes in duration; b. The safety of the public or Company personnel or the imminent failure of Company equipment is a factor leading to the interruption; or c. The interruption was due to work on the Customer’s meter.

Avista Utilities - 2022 Idaho Service Quality Program Report 25
required advance notification, the Company provided a $50 credit, for a total of $7,250. Compared to the 99.68% success rate in 2021, with only 38 customers not properly notified
out of a total of 11,768, 2022’s results for this measure, while a decrease, show a
consistently high (over 99%) success rate for the Company. Avista understands the importance of this benchmark and continues to refine and improve its prior notification processes.
Table No. 128 – Avista’s Customers Notified in Advance of a Service Interruption in 2022
Customer Service Guarantee Successful Missed $ Paid
Notify customers at least 24 hours in advance of a planned power outage lasting longer than 5 minutes 18,295 145 $7,250

Avista Utilities - 2022 Idaho Service Quality Program Report 26
Appendix A – Service Quality Program Report Card

ID 2022 Service Quality Program Results
Customer Service Measures Benchmark 2022 Performance Achieved
Percent of customers satisfied with our Contact Center services,
based on survey results At least 90%97%
Percent of customers satisfied with field services, based on survey
results At least 90%97%
Percent of calls answered live within 60 seconds by our Contact
Center At least 80%81%
Average time from customer call to arrival of field technicians in
response to electric system emergencies, per year
No more than 65
minutes 60
Average time from customer call to arrival of field technicians in
response to natural gas system emergencies, per year
No more than 55
minutes 40
Electric System Reliability
5-Year Average
(2018-2022)2022 Result Change in
5-Year Average
Frequency of non-major-storm power interruptions, per year, per
customer (SAIFI)0.96 0.92 -0.06
Length of power outages per year, per customer (SAIDI)141 146 -7
Customer Service Guarantees Successful Missed $$ Paid
Electric & Natural Gas service appointments 1,510 7 $350
Electric outage restoration within 24 hours of notification from
Customer, excluding major events 11,062 0 $0
Switch on power or connect gas services the same day of request 3,427 1 $50
Provide cost estimate for new electric or natural gas supply within
10 business days 1,333 0 $0
Investigate and respond to billing inquiries with 10 business days 498 0 $0
Investigate customer-reported problems with a meter, or conduct a
meter test, and report results within 20 business days 255 1 $50
Provide notification at least 24 hours in advance of disconnecting
service for scheduled electric interruptions 18,295 145 $7,250
Totals 36,380 154 $7,700
2022 Idaho Performance Highlights
Avista is pleased to report that the Company has once again exceeded all five of its Customer Service Measures. With
regard to customers satisfied with our Contact and Field services based on survey results, Avista achieved a 97%
satisfaction score for both categories. The Company also celebrates a 100% success rate for a third year in row in
restoring service within 24 hours of notification from customers after they have reported an electric outage, totaling
11,062 customers in 2022. Finally, Avista successfully met 99.58% of its applicable Customer Service Guarantees in 2022,
providing customers a guarantee credit in 154 out of 36,534 cases. The overall success rate of these Guarantees shows
Avista’s continued commitment to serving our customers. Avista is committed to pursuing further improvement in each
of these areas as we continue our mission of improving our customers' lives through innovative energy solutions by
providing safe, affordable, and reliable service now and into the future.

Avista Utilities - 2022 Idaho Service Quality Program Report 27
Appendix B - Definitions and Index Calculations
System Average Interruption Frequency Index (SAIFI): The average number of
sustained interruptions per customer, per year

• = The number of customers which had sustained interruptions Total number of customers served
• = ∑iN
TN

System Average Interruption Duration Index (SAIDI): The average sustained outage
time per customer, per year
• = Outage duration multiplied by the customers effected for all sustained interruptions
Total number of customers served
• = ∑iiNr
TN
Quantities: i = An interruption event; ri = Restoration time for each interruption event;
T = Total;
IDE = Number of interrupting device events;
Ni = Number of interrupted customers for each interruption event during the reporting period; NT = Total number of customers served for the area being indexed;
Major Event Day (MED): A day in which the daily system SAIDI exceeds a threshold value, TMED. For the purposes of calculating daily system SAIDI, any interruption that spans multiple calendar days is accrued to the day on which the interruption began. Statistically, days having a daily system SAIDI greater than TMED are days on which the
energy delivery system experienced stresses beyond that normally expected (such as severe weather). Activities that occur on major event days should be separately analyzed and reported. The purpose of MED is to allow major events to be studied separately from daily operation, and in the process, to better reveal trends in daily operation that would be hidden by the large statistical effect of major events.
TMED is calculated (taken from the IEEE 1366-2003 Standard) The major event day identification threshold value, TMED, is calculated at the end of each reporting period (typically one year) for use during the next reporting period as follows: a) Collect values of daily SAIDI for five sequential years ending on the last day of
the last complete reporting period. If fewer than five years of historical data are available, use all available historical data until five years of historical data are available.

Avista Utilities - 2022 Idaho Service Quality Program Report 28
b) Only those days that have a SAIDI/Day value will be used to calculate the TMED (do not include days that did not have any interruptions).
c) Take the natural logarithm (ln) of each daily SAIDI value in the data set.
d) Find a (Alpha), the average of the logarithms (also known as the log-average) of the data set. e) Find b (Beta), the standard deviation of the logarithms (also known as the log-standard deviation) of the data set.
f) Compute the major event day threshold, TMED, using equation (25).

TMED = e〈a+ 2.5 b)
g) Any day with daily SAIDI greater than the threshold value TMED that occurs
during the subsequent reporting period is classified as a major event day. Activities that occur on days classified as major event days should be separately analyzed and reported.
When an event has reached the threshold to constitute a MED described in subpart (f)
above, all outage incidents associated with the MED will be flagged in the Company’s Outage Management Tool. As the Company further assesses damage in the field while making repairs, new subsequent outage incidents that were a result of the MED may be created as more accurate information is made available. The subsequent incidents will be
flagged and included as part of original outage event and MED.