2023 ISQ Program Report.pdf

I 11
RECEIVED
Avista Corp. Tuesday, April 30, 2024 3:47PM
1411 East Mission Ave.,P.O. Box 3727 IDAHO PUBLIC
Spokane,WA 99220-0500 UTILITIES COMMISSION
Telephone: [phone]
Toll Free: 800-227-9187
April 30, 2024
Commission Secretary
Idaho Public Utilities Commission
11331 W. Chinden Blvd. Bldg. 8, Ste. 201-A
Boise, Idaho 83714
RE: Avista Utilities 2023 Idaho Service Quality(ISQ) Program Report
Dear Commission Secretary:
Attached for electronic filing is the 2023 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,
/4/,w. w Agrzw
Jaime Majure
Regulatory Affairs Manager
Avista Utilities

v
1
•� -, ,
Ilk
�• V4.
' 1
- , o
\ 4;w
v r.4 At c. r
i
Adbr
r
■
•
►V� 1t)
tt .
- r
ev
ev • • • I • •

Table of Contents
I. Introduction................................................................................................................... 2
II. Executive Summary...................................................................................................... 3
Customer Service Measures - Results for 2023.................................................................. 3
Electric System Reliability - Results for 2023.................................................................... 4
Customer Service Guarantees—Results for 2023............................................................... 6
III. Customer Service Measures.......................................................................................... 7
Measure 1: Customer Satisfaction with the Telephone Service provided by
Avista's CSRs............................................................................................................ 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..................................................................................... 18
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 ........................ 23
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-2023 Idaho Service Quality Program Report 1

I. Introduction
On December 28, 2017, the
Commission issued Order No. 33953
in Avista's general rate case,t
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. One such condition was a provision to
work with interested parties to
develop a service quality program
similar to that offered in Avista's Washington service territory — inclusive of Company
performance standards, a set of customer guarantees, and a reporting mechanism.
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 2023 annual
results of its ISQ Program, followed by a more in-depth explanation of the measures
themselves and associated annual outcomes.
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-2023 Idaho Service Quality Program Report 2

II. Executive Summary
In compliance with Order No. 34181 in Case Nos. AVU-E-18-10 and AVU-G-18-06,
Avista's 2023 ISQ Program Report (Report) provides the annual performance results for
the Company's ISQ Program for 2023. This is the Company's sixth year reporting
information regarding Customer Service Measures and Electric System Reliability for its
Idaho service territory, and its fifth 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 2023 Program year,
Avista is pleased to report the Company has again exceeded all five of its Customer Service
Measures. For the fourth year in a row, the Company also celebrates a 100% success rate
in restoring service within 24 hours of notification from customers after they have reported
an electric outage, totaling 9,395 customers in 2023. Finally, Avista successfully met
99.93% of its applicable Customer Service Guarantees in 2023, providing customers a
Guarantee credit in just 25 out of 36,503 cases.The overall success rate of these Guarantees
shows Avista's continued commitment to serving our customers.
Customer Service Measures - Results for 2023
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 2023.Avista achieved all of its customer service benchmarks for the year.
Table No. I —2023 Results for Avista's Customer Service Measures
Customer Service Measures Benchmark 2023 Achievje
Performance
Percent of customers satisfied with our Contact At least 90% 97%
Center services,based on survey results
Percent of customers satisfied with field At least 90% 97% ✓
services,based on survey results
Percent of calls answered live within 60 At least 80% 83% ✓
seconds by our Contact Center
Average time from customer call to arrival of No more than
field technicians in response to electric system 65 minutes 47 minutes ✓
emergencies,per year
Average time from customer call to arrival of No more than
field technicians in response to natural gas 55 minutes 46 minutes ✓
system emergencies,per year
Avista Utilities-2023 Idaho Service Quality Program Report 3

Electric System Reliability - Results for 2023
Table Nos. 2 and 3 below list the ServiceWashington and Idaho
two measures of electric system
reliability to be reported by
Avista each year as part of its Distriet0®
Loeur e'Alene—COC
ISQ Program. Because the <---�� " $endpoint cpmale—coc
• • Davenport—DAC
annual electric reliability results Deer Pork—OPC
Hot Graneavilk—GflC
S ok Coeur d'Alene l p Kellogavile—
often vary substantially year-to- eattle p . K Nogg lark l00
even ort •Kellogg. 0, o—OTC
year (the case for any electric Palouse �St Marl Palouse—PAC
° 1en1,,int-1AC
utility's system), it is difficult to h°"°- St Ma-s—SMC
DOanties
WA
derive a meaningful assessment ` ID
of the Company's system •Golden ale Lew' - I rk
e . e
reliability from any single-year's Stevenson La Grande.
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, 2023), and the historic "five-year rolling average" from 2010
— 2023. This data provides some context for better interpreting each year's reliability
results.
Table No. 2—2023 Results for Number of Outages on Avista's System (SAIFI)
q, 2023 Current 5-Year Previous 5-Year
Number10 tAverage
' I ' I I : I
Average number of sustained outages 0.79 0.96 .96
(interruptions)per customer for the year per Customer Per Customer Per Customer
(SAIFI)4
Table No. 3—Results for Duration of Outages on Avista's System in 2023 (SAIDI)
111 IPrevious
Outage1n am System Average Average
' I ' I (2018-2022)
Average duration of sustained outages
(interruptions)per customer for the 113 Minutes 138 Minutes 141 Minutes
year. (SAIDI)s
4 See Appendix B for a more detailed definition of these reliability measures and calculation of indices.
5 See Appendix B.
Avista Utilities-2023 Idaho Service Quality Program Report 4

Figure Nos. 1 and 2 below show
the "five-year rolling average"
F for each reliability measure from
r— -J 2010 through 2023. As shown in
r . A the figures, the long-term trend
r for each reliability measure is
stable during this period. The
Jib) _ trend in number of outages stays
the same while the outage
�N duration is declining, indicating
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, 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 2023 was 0.89, and the average total outage duration per customer was 149.29 minutes;
both figures constitute a decrease from the 1.06 outages per customer and 163.95 duration
reported for 2022.
Figure No. 1 — Historic Five-Year Rolling Average for Number of Electric Outages on
Avista's Electric System (SAIFI)
Historic Five-Year Averages of the Annual Number of
Outages
(SAIFI)
t.1 1.09
(7 1D5
Q
1.02
O
� 1
W 0.96 0.96
m
0.9` Q9l
z
0.9
0.85
ti�1A ti�y� ti�1� ti�1� ti�1� ti�1� x"
1�10 ti�11 ti�1� ti�1� ti�1a ti�1� ti�16 ti��� ti�1� ti�1�
Avista Utilities-2023 Idaho Service Quality Program Report 5

Figure No. 2 —Historic Five-Year Rolling Average for Duration of Outages on Avista's
Electric System (SAIDI)
Historic Five-Year Averages of Annual Outage Duration
(SAIDI)
160 151 149 is1
148
140 136
139 142 142 141 138
z_ 120
p 100
c
80
C7
F 60
O
40
20
0
.ti07� .1,0,ti .LO.y'L 'LOti�' .L07� ti�1� 0,�ti� ti�1� ti�1� ti�1�
Customer Service Guarantees — Results for 2023
Avista's 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 2023.
Avista Utilities-2023 Idaho Service Quality Program Report 6

Table No. 4—2023 Results for Avista's Customer Service Guarantees
Customer Service Guarantee SuccessfuA Missed $Paid
Keeping Our Electric and Natural Gas Service 1,501 1 $50
Appointments scheduled with our customers
Restore service within 24 hours of a customer 99395 0 $0
reporting an outage(excluding major storm events)
Turn on power the same day the request is received 3,507 2 $100
Provide a cost estimate for new electric or natural
gas service within 10 business days of receiving 1,384 0 $0
the request
Investigate and respond to a billing inquiry within
10 business days if unable to answer a question on 448 0 $0
first contact
Investigate a reported meter problem or conduct a
meter test and report the results within 20 business 251 1 $50
days
Notify customers at least 24 hours in advance of a 19,992 21 $1,050
planned power outage lasting longer than 5 minutes
Totals 36,478 25 $1,250
III. Customer Service Measures
There are numerous touchpoints where customers interact with Avista, each playing a
pivotal role in shaping customer perception of the Company and the level of satisfaction
derived from our services. While Avista has tracked its customers' satisfaction with
primary services such as customer contact center and field services for many years,we are
equally invested in understanding whether we are meeting broader service expectations. In
response to this interest, Avista conducts its Voice of the Customer (VOC) survey, which
prompts customers to evaluate their overall satisfaction with our Company's services. This
holistic measure serves as a crucial indicator of how satisfied our customers are with the
entirety of the integrated services and value provided by Avista. As depicted in Figure No.
3 below, Avista's overall customer satisfaction, encompassing both satisfied and very
satisfied responses, has consistently ranged between 94% and 97% over the past decade.
Avista Utilities-2023 Idaho Service Quality Program Report 7

Figure No. 3 — Percent of Customers Satisfied or Very Satisfied with Avista's Overall
Service Level 2014-2023
Percent of Customers Satisfied or Very Satisfied with
Avista's Overall Service 2014-2023
100 -
0 96 97 96 96 97 97
95 95
LL 94 94
W 90
Cr
0
W
V)
N
Q v) 80
z
z
U
W
d
70
2014 2015 2016 2017 2018 2019 2020 2021 2022 2023
These results align closely with the satisfaction levels reported for our contact center and
field services, as reported for the ISQ Program during this same time period. Accordingly,
we are confident that the outcomes of the five Customer Service Measures outlined in the
subsequent sections collectively offer a reasonable evaluation of our customers' overall
satisfaction with the quality and value of our services.
Measure 1: Customer Satisfaction with the Telephone Service provided by Avista's
Customer Service Representatives (CSRs)
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;
Avista Utilities-2023 Idaho Service Quality Program Report 8

Several factors play a significant role in influencing our customers' satisfaction with the
quality of telephone service delivered by our Customer Service Representatives (CSRs)
and contact center. We annually assess the importance of these factors to our customers,
along with their satisfaction levels. The factors,along with our customers'satisfaction rates
(either satisfied or very satisfied) for each factor in 2023, are outlined below.
✓ The CSR handling the customer's call in a friendly, caring manner. (99%)
✓ The CSR being informed and knowledgeable. (97%)
✓ The CSR meeting the customer's needs promptly. (98%)
✓ The CSR giving the customer all the information they need in one call. (96%)
✓ Being connected to a CSR in a reasonable amount of time. (96%)
2023 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 CSRs.
Table No. S—Customer Satisfaction with Avista's Contact Center Representatives in 2023
CustomerI
Contacti
Percent of customers either satisfied or very 90%or
satisfied with the Quality of Avista's Greater 97%
Customer Contact Center Representatives Satisfied
For the purposes of reporting our annual service quality performance under this Program,
the Company will continue utilizing its system-wide results, but 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 2023,the percent of Idaho customers satisfied or very
satisfied with the Company's CSRs and contact center was 97%, with 91% of our
customers noting they were "very satisfied" and 6% noting they were "satisfied". While
only a slight increase from the overall 96% satisfaction rate reported in 2022, there was a
marked increase in the percentage of customers noting "very satisfied", from 88%to 91%
(thereby resulting in a decrease for"satisfied", from 9%to 6%).
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.
Avista Utilities-2023 Idaho Service Quality Program Report 9

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%.1
The quality of our field services and the satisfaction of our customers are influenced by
several key factors. Annually, we gauge the significance of these factors to our customers
and assess their satisfaction with each aspect of our service. Below are these factors, along
with our customers' satisfaction levels (either satisfied or very satisfied) with each factor
in 2023.
✓ The service representative keeping you informed of the status of your job. (95%)
✓ The service representative or service crew being courteous and respectful. (99%)
✓ The service representative or service crew being informed and knowledgeable.
(98%)
✓ The service representative or service crew leaving your property in the condition
they found it. (97%)
✓ The service work being completed according to the customer's expectations.(97%)
✓ The overall quality of the work performed by Avista Utilities. (98%)
2023 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 in 2023.
7 The level of Customer satisfaction with the Company's field services 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;
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.
Avista Utilities-2023 Idaho Service Quality Program Report 10

Table No. 6— Customer Satisfaction with Avista's Field Services Representatives in 2023
ustomer Satisfaction with Avista's 6service 2023 Achieved
ervices Representatives 141ruality Performance
Percent of customers either satisfied or very 90%or
satisfied with the Quality of Avista's Field Greater 97% ✓
Service Representatives Satisfied
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,but 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 2023,the percent
of Idaho customers satisfied or very satisfied with the Company's field service
representatives paralleled the system-wide results at 97%, with over 87% of customers
"very satisfied" and nearly 10% "satisfied" with the quality of our field services.8 These
results are a slight improvement over the 2022 satisfaction rate of 96%,with an increase in
customers noting "very satisfied" (from 85% in 2022), and associated decrease in
"satisfied" from last year's 12%.
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 CSR within 60 seconds will average 80%
or greater.9
This particular customer service measure serves as one of the subsets of service attributes
contributing to customers' overall satisfaction with our CSRs and contact center.
Commonly 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 CSR. When a customer calls
'The percentage of Idaho customers"very satisfied"was rounded from approximately 87.5%,and"satisfied"
was rounded from 9.8%.
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-2023 Idaho Service Quality Program Report I I

Avista's contact center, their call is initially received by our automated (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 connecting with a live
CSR to address their service needs. 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). Recognizing that achieving a higher service level
demands increased staffing levels and may entail additional costs to customers, Avista has
prioritized lower-cost or no-cost measures such as effective employee training and
coaching to attain superior standards in attributes like courtesy, empathy, knowledge, and
proficiency, to maintain our exceptionally high level of overall customer satisfaction with
our CSRs and contact center.
In addition to responding to customers effectively, Avista has implemented measures to
help reduce the overall volume of customer calls, which then helps to reduce the service
costs borne 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. This work has helped to not
only reduce the volume of calls to our contact center and maintain a high level of service
at lower cost,but also enhance the overall customer experience and satisfaction.
2023 Results—Avista's customers made a total of 517,649 qualifying calls to the Company
that were answered live by a CSR in 2023. Of these calls, 430,440 were answered live in
60 seconds or less, for a GOS of approximately 83%, as shown in Table No. 7 below.
Table No. 7—Percent of Avista's Customer Calls Answered Live within 60 Seconds in 2023
'k Percent of Avista's Customer Calls Service 2023 Achieved
Answered Live Within 60 Seconds
Percent of Avista's customer calls answered 80% or 83% ✓
live by a CSR within 60 seconds Greater
Avista Utilities-2023 Idaho Service Quality Program Report 12

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.ro
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 efforts commence once the site is safely secured and necessary resources are
present. 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.
2023 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 236 qualifying electric emergency reports in
its Idaho service area in 2023, which had a cumulative response time of 10,968 minutes.
The resulting average for was nearly 47 minutes (rounded up), as noted in Table No. 8
below.
io 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-2023 Idaho Service Quality Program Report 13

Table No. 8—Avista's Response Time for Electric Emergencies in 2023
Response for I
Emergencies Quality Performance
Average time from customer call to the arrival 65 Minutes
of Avista's field technicians in response to or Less 47 Minutes ✓
electric system emergencies
.,
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.]]
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 efforts can
commence once the safety of the site is secured,and necessary 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
conditions, traffic, and the presence of other simultaneous emergency events across the
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-2023 Idaho Service Quality Program Report 14

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.
2023 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 2,387 qualifying natural gas emergency reports in its
Idaho service area in 2023,which had a cumulative response time of 110,816 minutes. The
resulting average for 2023 was approximately 46 minutes, as noted in Table No. 9 below.
Table No. 9—Avista's Response Time for Natural Gas Emergencies in 2023
'Wista's Response i2023 Achiev
Emergencies Quality 01 Performanc4l
Average time from customer call to the arrival 55 Minutes
of Avista's field technicians in response to or Less 46 Minutes ✓
natural gas system emergencies
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,Avista monitors
and tracks various aspects of the reliability performance of our system each year,utilizing
industry-standard measures (or indices) to ensure optimal performance. Two of the most-
commonly reported measures are 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-2023 Idaho Service Quality Program Report 15

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 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 2023. 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-2023 Idaho Service Quality Program Report 16

r 1
r
.I r
Measure 1: Number of Electric System Outages
As part ofAvista'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
(SA IFI).13
2023 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 2023
result of 0.79 outages per customer is a decrease from the prior year's result of 0.92 outages
per customer, as well as from the average value for both the current and previous five-year
periods (2019-2023 and 2018-2022, respectively) of 0.96. For 2023, our Idaho-only result
was 0.89 outages per customer.
Table No. 10 —Number of Electric System Outages for the Average Avista Customer in
2023
Number of I i
Outages
CustomerI ' IAverage
Number of sustained interruptions in 0.79 0.96 -0.004
electric service for the average Avista per Customer Per Customer Per Customer
customer for the year(SAIFI)
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.
1a Any service interruption that is greater than five minutes in duration.
Avista Utilities-2023 Idaho Service Quality Program Report 17

t
fj
Measure 2: Average Duration of Electric System Outages
As part ofAvista'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
(SA IDI).15
2023 Results—This measure, as noted earlier,represents the average duration or length of
outages for the year. Outage duration 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 2023 outage duration decreased to 113 minutes,
33 minutes lower than the 146-minute duration reported for 2022. As shown in Table No.
11 below,the current five-year average resulted in a 2.6 minute decrease to the average for
the current five-year period (2019-2023). The Idaho-only outage duration was 149.29
minutes for 2023, a decrease from 163.95 minutes for 2022. 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 2023
otal Outage Duration forChange2023 Current
Average Avista Customer A System 5 Year Average J
Results (2019-2023) Average
Total duration of all electric service 113 138 -2.6
outages for the average Avista Minutes Minutes Minutes
customer for the year(SAIDI)
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
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
and Idaho as well as for Idaho only.
Avista Utilities-2023 Idaho Service Quality Program Report 18

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 2023 Idaho
Service Quality Report is the second Report to contain the results of Avista's Guarantees.
The Company met • • • ' of our applicable 1 1
Programthe 2023 providing 1 -- credit in only
25 out of 36,503cases.
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.
—12:00p.m. or 12:00 p.m. —S: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
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.
2023 Results — In 2023, Avista was able to successfully keep 99.93% of its 1,502
scheduled customer appointments for applicable electric and natural gas services in Idaho,
and issued one Guarantee credit during the year. The primary factor contributing to missed
appointments continues to be the occurrence of emergency work orders during the day,
which prevent the Company from adhering to its scheduled appointment times. Due to the
risks and danger of electric and natural gas emergencies, the Company prioritizes
i6 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)
Avista Utilities-2023 Idaho Service Quality Program Report 19

emergency orders over all service work. While this prioritization is necessary for ensuring
public safety, it occasionally results in the Company missing appointments, as evidenced
by the 2023 results.
Table No. 12—Avista Service Appointment Results for 2023
Customer Service Guarantee go Successful Missed $Paid
Keeping Our Electric and Natura7Ga
Service Appointments scheduled 1,501 1 $50
customers
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.1 7
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. Some years, even in cases where Avista does not experience any storms
that qualify as major events, various factors may make it impossible for the Company 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 2023 Program year, Avista did not
provide any Guarantee credits to customers in Idaho, as we successfully restored service
to all impacted customers within the benchmark timeframe.
2023 Results — In 2023, Avista's Idaho customers encountered a total of 9,395 outage
events. Remarkably, all of these outages had power restored within 24 hours, resulting in
a success rate of 100%. Avista takes pride in the ongoing effectiveness of its efforts,which
have consistently minimized the number of missed outage events. The Company is pleased
to maintain its high success rate in swiftly restoring power to its customers within the 24-
hour timeframe, ensuring minimal disruption and enhancing overall customer satisfaction.
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-2023 Idaho Service Quality Program Report 20

Table No. 13—Avista's Outage Restoration Results for 2023
Customer Service Guarantee Successful Missed $Paid
Restore service within 24 hours of a
customer reporting an outage(excluding 9,395 0 $0
major storm events)
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.
2023 Results —Avista met its benchmark to turn on our customers' service the same day
the service was requested in 99.94% of cases, missing two of the 3,509 requests received.
Table No. 14—Avista Turning on Service the Same Day for 2023
mer Service Guaranteams Successful Missed Paid
Turn on power within a business day of 3,507 2 $100
receiving the request
18 Except for the following instances:
a. The service request is received by the Company after 7:OOpm 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-2023 Idaho Service Quality Program Report 21

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, and/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.
2023 Results —In 2023, the Company received 1,384 requests for new electric or natural
gas service. Impressively, Avista successfully delivered cost estimates for each request
within 10 business days of receipt, achieving a remarkable success rate of 100%. This
accomplishment marks the fifth consecutive year, since the Company's inception of
reporting these Guarantees in 2019, in which Avista has maintained a flawless success rate
of 100%.
Table No. 15—Avista Providing Customers a Cost Estimate for New Service in 2023
Customer Service Guarantee Successful Missed $Paid
Provide a cost estimate for new electric or
natural gas service within 10 business days 1,384 0 $0
of receiving the request
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.
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 during 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:
Avista Utilities-2023 Idaho Service Quality Program Report 22

✓ 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 a CSR encounters a billing inquiry that cannot be resolved during the initial contact,
or if the customer remains dissatisfied,Avista initiates a comprehensive case investigation
to further examine the customer's issue. Following the creation of a case, Avista verifies
the meter read or obtains a new meter read to determine the accuracy of the metered usage.
If a billing error is identified, the CSR will initiate sending a corrected bill. After
confirming the accuracy of the bill,the CSR revisits the inquiry with the customer, sharing
the results of the verification process. This thorough process typically leads to a resolution
that satisfies the customer. In cases where satisfaction is not achieved, and/or a customer
requests a meter test to verify their meter is reading accurately, a separate process is
triggered, covered by Customer Service Guarantee number six below, "Promptly
Responding to Customers' Meter Problems."
2023 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 448 follow-up inquiries received in 2023.
Table No. 16—Avista Responding to Customer's Bill Inquiries in 2023
Customer Service Guara I Successful Missed $Paid
Investigate and respond to a billing inquiry
within 10 business days if unable to answer 448 0 $0
a question on first contact
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 requirements for meter testing, and 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.
Avista Utilities-2023 Idaho Service Quality Program Report 23

2023 Results—In 2023,252 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 99.60%.
Table No. 17—Avista Resolving Meter Problems in 2023
Customer Service Guarantee Successful Missed $Paid
Investigate a reported meter problem or
conduct a meter test and report the results 251 1 $50
within 20 business days
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,
CPCs, 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.
2023 Results — In 2023, a total of 20,013 Idaho customers were affected by scheduled
service interruptions. Avista successfully notified 19,992 customers, achieving a success
rate of 99.89%. For each of the 21 customers that did not receive the required advance
notification,the Company provided a$50 credit,totaling $1,050. This success rate reflects
an improvement from the 99.21% reported in 2022, and the reduction in 2023 can be
attributed to fewer internal errors and improvements implemented to address gaps in our
processes, resulting in a higher success rate in notifying customers of planned outage
events. Avista acknowledges the significance of this benchmark and remains committed to
refining and enhancing its prior notification processes to better serve its customers.
i9 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-2023 Idaho Service Quality Program Report 24

Table No. 128—Avista's Customers Notified in Advance of a Service Interruption in 2023
NEL Customer Service Guarantee Successful Missed $Paid
Notify customers at least 24 hours in
advance of a planned power outage lasting 19,992 21 $1,050
longer than 5 minutes
Avista Utilities-2023 Idaho Service Quality Program Report 25

Appendix A—Service Quality Program Report Card
ID 2023 Service Quality Program Results
Customer Service Measures Benchmark 2023 Performance Achieved
Percent of customers satisfied with our Contact Center services,
based on survey results At least 90% 97.0%
Percent of customers satisfied with field services,based on survey /
results At least 90% 97.0% V
Percent of calls answered live within 60 seconds by our Contact
Center At least80% 83.0%
Average time from customer call to arrival of field technicians in No more than 65
response to electric system emergencies,per year minutes 47
Average time from customer call to arrival of field technicians in No more than 55
response to natural gas system emergencies,per year minutes 46
5-Year Average 2023 Result Change in
Electric System Reliability (2019-2023) 5-Year Average
Frequency of non-major-storm power interruptions,per year,per
c 0.96 0.79 0.004
customer(SAIFI)
Length of power outages per year,per customer(SAIDI) 138 113 -2.6
Customer Service Guarantees Successful Missed $$Paid
Electric&Natural Gas service appointments 1,501 1 $50
Electric outage restoration within 24 hours of notification from 9,395 0 $0
Customer,excluding major events
Switch on power or connect gas services the same day of request 3,507 2 $100
Provide cost estimate for new electric or natural gas supply within
10 business days 1,384 0 $0
Investigate and respond to billing inquiries with 10 business days 448 0 $0
Investigate customer-reported problems with a meter,or conduct a
meter test,and report results within 20 business days 251 1 $50
Provide notification at least 24 hours in advance of disconnecting
service for scheduled electric interruptions 19,992 21 $1,050
Totalsl 36,478 1 25 1 $1,250
2023 Idaho Performance Highlights
During its 2023 Program year,Avista is pleased to report the Company has again exceeded all of its Customer Service
Measures.For the fourth year in a row,the Company also celebrates a 100%success rate in restoring service within 24 hours
of notification from customers after they have reported an electric outage,totaling 9,395 customers in 2023.Finally,Avista
successfully met 99.93%of its applicable Customer Service Guarantees in 2023,providing customers a guarantee credit in 25
out of 36,503 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-2023 Idaho Service Quality Program Report 26

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
• _ YN;
NT
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
r N,
NT
Quantities:
i= An interruption event;
rl = 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;
Maior Event Day (MEM 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-2023 Idaho Service Quality Program Report 27

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(In) 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.
Avista Utilities-2023 Idaho Service Quality Program Report 28