2024Avista ID State Electric Annual Report.pdf

IDAHO STATE ELECTRIC ANNUAL REPORT
Name of Respondent Avista Corporation
This report is(original, resubmission) Original
Date of report 4'FE7 25
Year/period of report12024/44

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation K] An Original mm/dd/yyyy End of 2024/Q4
A Resubmission 4/18/2025
STATEMENT OF UTILITY OPERATING INCOME-IDAHO
Instructions
1. For each account below,report the amount attributable to the state of Idaho based on Idaho jurisdictional Results of Operations.
2. Provide any necessary important notes regarding this statement of utility operating income in a footnote in the available space at the bottom of this
Line Refer to TOTAL SYSTEM-IDAHO
No. Account Form 1 Current Year Prior Year
Page
(a) (b) (c) (d)
1 UTILITY OPERATING INCOME
2 1 Operating Revenues 400 300-301 561,477,729 512,985.949
3 Operating Expenses
4 Operation Expenses 401 320-323 359.738.975 336.497.110
5 Maintenance Expenses 402) 320-323 28,845,440 26.436.728
6 Depreciation Expense 403 336-337 57,781,419 59,081,789
7 Depreciation Expense for Asset Retirement Costs(403.1) 336-337
8 Amortization&Depletion of Utility Plant 404-405 336-337 18.394.351 16.655.751
9 Amortization of Utility Plant Acquisition Adjustment 406 336-337 - -
10 Amort.of Property Losses,Unrecov Plant and Regulatory Study Costs(407)
11 Amortization of Conversion Expenses 407 - -
12 Regulatory Debits(407.3) 7.473.269 4.166.247
13 Less Regulatory Credits 407.4 (19.188,217) (15.806.967)
14 Taxes Other Than Income Taxes 408.1 262-263 15,451,321 17,147.479
15 Income Taxes-Federal 409.1 262-263 12.031,975 303,077
16 -Other(409.1) 262-263 -
17 Provision for Deferred Income Taxes(410.1) 234,272-277 7,703,439 (9.010.501
18 Less Provision for Deferred Income Taxes-Cr 411.1) 234,272-277
19 Investment Tax Credit Adjustment-Net(411.4) 266 (249.173) (172,197)
20 (Less)Gains from Disposition of Utility Plant 411.6)
21 Losses from Disposition Of Utility Plant(411.7)
22 (Less)Gains from Disposition of Allowances 411.8)
23 1 Losses from Disposition of Allowances 411.9)
24 JAccretion Expense 411.10
25 TOTAL Utility Operating Expenses Total of line 4 through 24) 472.575.921 434,692,362
26 Net Utilitv Operating Income(Total line 2 less 25) 88.901.808 1 78,293.587
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID 114-115

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation XD An Original mm/dd/yyyy End of 2024/Q4
0 A Resubmission 4/18/2025
STATEMENT OF UTILITY OPERATING INCOME-IDAHO
Instructions
page or in a separate schedule.
3. Explain in a footnote if the previous year's figures are different from those reported in prior reports.
ELECTRIC UTILITY GAS UTILITY OTHER UTILITY Line
Current Year Prior Year Current Year Prior Year Current Year Prior Year No.
(e) (f) (g) (h) 0) G)
1
439.522.361 391,413,522 121,955,368 121,572.427 2
3
268,230,081 243.415.359 91,508,894 93.081,751 4
25,620,893 23.316.905 3,224,547 3119.823 5
49.047,297 49,909,930 8,734,122 9,171,859 6
7
15.139,844 13,551,081 3,254,507 3.104.670 8
_ 9
_ 10
11
6,890,908 3,902.138 582.361 264.109 12
16.588,338 12,808,982 2,599,879 2,997,985 13
12,625,016 13,765,709 2.826.305 3,381,770 14
6,673,662 594,238 5,358,313 291.161 1 15
- 16
2,363.741 8,745.603 5.339.698 264,898) 17
18
(249,173) (172,197) 19
20
21
22
23
24
365,026.449 325.540,102 107,549.472 109,152,260 - 25
74.495.912 65,873,420 14,405.896 12,420,167 26
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.114-115

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation ] An Original mm/dd/yyyy End of 2024/Q4
A Resubmission 4/18/2025
SUMMARY OF UTILITY PLANT AND ACCUMULATED PROVISIONS FOR DEPRECIATION,AMORTIZATION AND DEPLETION-IDAHO
Instructions
1. Report below the original cost of utility plant in service necessary to furnish utility service to customers in the state of Idaho,and the
accumulated provisions for depreciation,amortization,and depletion attributable to that plant in service.
2. Report in column(c)the amount for electric function,in column(d)the amount for gas function,in columns(a),(f),and(g)report other(specify),
Line Total Company
No. Account End of Current Year Electric
(a) (b) (c)
1 Utility Plant
2 In Service
3 Plant in Service(Classified) 2.472.922.103 1,893,141.429
4 Property Under Capital Leases 20.148.242
5 Plant Purchased or Sold _
6 Completed Construction not Classified
7 lExperimental Plant Unclassified
8 ITotal(Total lines 3 through 7) 2.493.070.345 1,893,141.429
9 1 Leased to Others _
10 lHeld for Future Use 5,698,150 5,698.150
11 Construction Work in Progress 67.950.680 59.883,932
12 JAcquisition Adjustments _
13 1 Total Utility Plant Total lines 8 through 12) 2,566,719.175 1.958.723.511
14 JAccumulated Provision for Depreciation,Amortization,and Depletion 955,219,712 734.327.041
15 Net Utility Plant Line 13 less line 14 1.611,499 463 1,224,396,470
16 Detail of Accumulated Provision for Depreciation,Amortization.and Depletion
17 In Service
18 Depreciation 885.110,311 719.864.360
19 Amortization and Depletion of Producing Natural Gas Lands/Land Rights
20 Amortization of Underground Storage Lands!Land Rights _
21 Amortization of Other Utility Plant 70,109,401 14.462.681
22 Total Total lines 18 throw h 21) 955,219,712 734,327.041
23 Leased to Others
24 Depreciation _
25 JAmortization and Depletion
26 ITotal Leased to Others
27 1 Held for Future Use
28 Depreciation
29 Amortization
30 Total Held for Future Use
31 Abandonment of Leases(Natural Gas)
32 Amortization of Plant Acquisition Adjustment _
33 Total Accumulated Provision[total lines 22,26,30.31,321 1 955.219,712 1 734.327.041
(1)A small portion of the Company's electric distribution plant is located in Montana.For jurisdictional reporting purposes,those amounts are
included as Idaho plant.
(2)Common Property Under Capital Leases are comprised of ROU Assets
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E ID 200-201

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation R I An Original mm/dd/yyyy End of 2024/Q4
A Resubmission 4/18/2025
SUMMARY OF UTILITY PLANT AND ACCUMULATED PROVISIONS FOR DEPRECIATION,AMORTIZATION AND DEPLETION-IDAHO
Instructions
and in column(h)common function.
3. In order to accurately reflect utility plant in service necessary to furnish utility service to customers in the state of Idaho,electric and gas
plant not directly assigned is allocated to the state of Idaho as appropriate and included in column(c)and(d).
Line
Gas Other(Specify) Other(Specify) Other(Specify) Common No.
(d) (e) M (g) (h)
1
2
358,443,942 221,336,732 3
- 20,148,242 4
5
6
7
358,443.942 241.484.974 8
9
10
3.024,863 5.041,885 11
12
361.468,805 246.526,859 13
126,404.457 94,488.214 14
235.064,348 152.038.645 15
16
17
126.069,552 39.176,399 18
19
20
334.905 55,311,815 21
126.404.457 94.488.214 22
23
24
25
26
27
28
29
30
31
32
126.404,457 94,488,214 33
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.200-201

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation X❑ An Original mm/dd/yyyy End of 2024/Q4
❑ A Resubmission 4/18/2025
ELECTRIC PLANT IN SERVICE-IDAHO(Account 101,102,103 and 106)
Instructions
1. Report below the original cost of electric plant in service necessary to furnish electric utility service to customers in the state of Idaho.
Include electric plant not directly assigned as allocated to the state of Idaho.
2. In addition to Account 101,Electric Plant in Service(Classified),this page and the next include Account 102,Electric Plant Purchased or Sold;
Account 103,Experimental Electric Plant Unclassified;and Account 106,Completed Construction Not Classified-Electric.
3. Include in column(c)or(d),as appropriate,corrections of additions and retirements for the current or preceding year.
4. For revisions to the amount of initial asset retirement costs capitalized,include by primary plant account increases in column(c),additions,and
reductions in column(e),adjustments.
5. Enclose in parentheses credit adjustments of plant accounts to indicate the negative effect of such amounts.
6. Classify Account 106 according to prescribed accounts,on an estimated basis if necessary,and include the entries in column(c). Also to be included
in column(c)are entries for reversals of tentative distributions of prior year in column(b). Likewise,if the respondent has a significant amount of plant
retirements which have not been classified to primary accounts at the end of the year,include in column(d)a tentative distribution of such retirements,
on an estimated basis,with appropriate contra entry to the account for accumulated depreciation provision. Include also in column(d)distributions of
Line Balance
No. Account Beginning of Year Additions
(a) (b) (c)
1 1.INTANGIBLE PLANT
2 301 Organization
3 302 Franchises and Consents 15.646.282
4 303 Miscellaneous Intangible Plant 16.313,430 1.794.886
5 'TOTAL Intangible Plant Total of lines 2,3,and 4) 31 959,712 1.794.886
6 2.PRODUCTION PLANT
7 A.Steam Production Plant
8 310 Land and Land Rights 1.370,213 -
9 311 Structures and Improvements 49.265.111 347,025
10 312 Boiler Plant Equipment 81,241.244 347.009
11 1 313 Engines and Engine-Driven Generators 82.820 347,010
12 314 Turbogenerator Units 20,356,800 347.008
13 315 Accessory Electric Equipment 10,796.074 347,004
14 316 Miscellaneous Power Plant Equipment 6.040,386 347,007
15 317 Asset Retirement Costs for Steam Production - -
16 TOTAL Steam Production Plant Total of lines 8 through 15) 169.152,648 2,082,063
17 B.Nuclear Production Plant
18 1 320 Land and Land Rights
19 321 Structures and Improvements
20 322 Reactor Plant Equipment
21 323 Turbogenerator Units
22 324 Accessory Electric Equipment
23 325 Miscellaneous Power Plant Equipment
24 326 Asset Retirement Costs for Nuclear Production
25 1 TOTAL Nuclear Production Plant Total of lines 18 throw h 24 -
26 C.H draulic Production Plant
27 330 Land and Land Rights 24.347,275 13,269
28 331 Structures and Improvements 41,487.974 2.538.050
29 332 Reservoirs,Dams,and Waterways 94,582.329 2,787,452
30 333 Water Wheels,Turbines,and Generators 83,838.793 282,826
31 334 Accessory Electric Equipment 30,502,255 8,886,736
32 335 Miscellaneous Power Plant Equipment 5.105.267 118,212
33 336 Roads,Railroads,and Bridges 1,381.073 32,687
34 337 Asset Retirement Costs for Hydraulic Production -
35 TOTAL Hydraulic Production Plant Total of lines 27 through 34 281,244,966 14.659,232
36 D.Other Production Plant
37 340 Land and Land Rights 321,516 -
38 341 Structures and Improvements 6,251.464 22,596
39 342 Fuel Holders,Products,and Accessories 7,484.429 715
40 1 343 Prime Movers 7.611.862 -
41 344 Generators 85,347.980 584.587
42 345 Accessory Electric Equipment 9.434,216 166,785
43 346 Miscellaneous Power Plant Equipment 577.789 359
44 347 Asset Retirement Costs for Other Production
45 TOTAL Other Production Plant Total of lines 37 through 44 117,029,256 1 775,042
46 TOTAL Production Plant(Total of lines 16,25,35,and 45) 567.426:870 1 17,516,337
(1)A small portion of the Company's electric distribution plant is located in Montana. For jurisdictional reporting purposes,those amounts are
ncluded as Idaho plant.
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.204-205

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation XD An Original mm/dd/yyyy End of 2024/Q4
0 A Resubmission 4/18/2025
ELECTRIC PLANT IN SERVICE-IDAHO(Account 101,102,103 and 106)
Instructions
these tentative classifications in columns(c)and(d),including the reversals of the prior year's tentative account distributions of these amounts. Careful
observance of these instructions and the texts of Accounts 101 and 106 will avoid serious omissions of the reported amount of respondent's plant
actually in service at end of year.
7. Show in column(f)reclassifications or transfers within utility plant accounts. Include also in column(f)the additions or reductions of primary account
classifications arising from distribution of amounts initially recorded in Account 102;include in column(e)the amounts with respect to accumulated
provision for depreciation,acquisition adjustments,etc.,and show in column(f)only the offset to the debits or credits distributed in column(f)to primary
account classifications.
8. For account 399,state the nature and use of plant included in this account,and,if substantial in amount,submit a supplementary statement showing
subaccount classification of such plant conforming to the requirement of these pages.
9. For each account comprising the reported balance and changes in Account 102,state the property purchased or sold,name of vendor or purchase,and
date of transaction. If proposed journal entries have been filed as required by the Uniform System of Accounts,give also the date of such filing.
Balance Line
Retirements Adjustments Transfers End of Year No.
(d) (e) (f) (g)
1
2
295,130 15.351,152 3
1.130.837 148,950 17,126.429 4
1,130.837 146,180 32,477,581 5
6
7
(25,845) 1,344,368 8
399.525 49.212.611 9
81,042 438,740 81,068,471 10
6,675 436,505 11
1,528 100,440 20,601,840 12
20,443 (77,523) 11,045.112 13
41,049 6,428,442 14
15
103,013 (994,349) 170,137,349 16
17
18
19
20
21
22
23
24
_ - 25
26
(515,222) 23,845.322 27
265.899 (1,885,846) 41.874.279 28
62,296 (3,357,772) 93,949,713 29
16,095 1.731,074 82,374,450 30
68,679 5,805,854 33,514,458 31
6,834 (107,612 5,109,033 32
(47,346) 1,366,414 33
34
419.803 13,450,726 282,033,669 35
36
6.065 315,451 37
41,172 102,681 6.130,207 38
(141.178) 7,343,966 39
6,306 (149.348) 7,456,208 40
66,424 (1,462,126) 84,404,017 41
27,377 (3LL21 9.534,235 42
721 10,899 566,528 43
44
142.000 1,911,686 115.750.612 45
664.816 (16,356,761)1 567.921,630 46
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.204-205

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation XD An Original mm/dd/yyyy End of 2024/Q4
A Resubmission 4/18/2025
ELECTRIC PLANT IN SERVICE-IDAHO(Account 101,102,103 and 106)(Continued)
Line Balance
No. Account Beginning of Year Additions
(a) (b) (c)
47 3.TRANSMISSION PLANT
48 350 Land and Land Rights 10.742.259 22.681
49 352 Structures and Improvements 13.277,638 47.088
50 353 Station Equipment 137-794.333 19.524.667
51 354 Towers and Fixtures 5.948,871 45.820
52 355 Poles and Fixtures 135.450.390 12,647,544
53 356 Overhead Conductors and Devices 67.675,339 1.942.593
54 357 Underground Conduit 1,141,590 247.430
55 358 Underground Conductors and Devices 2,376.811 247,430
56 359 Roads and Trails 925.724 -
57 359.1 Asset Retirement Costs for Transmission Plant
58 TOTAL Transmission Plant Total of lines 48 throw h 57 375,332,955 34.725.253
59 14.DISTRIBUTION PLANT
60 360 Land and Land Rights 4.664.052 2.709.510
61 361 Structures and Improvements 7,688.052 1.246,623
62 362 Station Equipment 55,180.943 7.911.593
63 363 Storage Battery Equipment -
64 364 Poles,Towers,and Fixtures 197,447,259 12,578,180
65 365 Overhead Conductors and Devices 136.289.321 9.797,667
66 366 Underground Conduit 58.783,591 3,926,671
67 367 Underground Conductors and Devices 98.440,969 5,931,533
68 368 Line Transformers 107.490.218 7.223.911
69 369 Services 79.919.086 4,136.674
70 370 Meters 24,794,861 205.400
71 371 Installations on Customer Premises -
72 372 Leased Property on Customer Premises _
73 373 Street Lighting and Signal Systems 28.680.650 1,239,454
74 374 Asset Retirement Costs for Distribution Plant
75 ITOTAL Distribution Plant Total of lines 60 through 74 799.379.002 56,907.216
76 15.REGIONAL TRANSMISSION AND MARKET OPERATION PLANT
77 380 Land and Land Rights
78 381 Structures and Improvements
79 382 Computer Hardware
80 383 Computer Software
81 384 Communication Equipment
82 385 Miscellaneous Regional Transmission and Market Operation Plant -
83 1 386 Asset Retirement Costs for Regional Transmission and Operation Plant -
84 1 TOTAL Transmission and Market Operation Plant Total lines 77 through 83
85 16.GENERAL PLANT
86 389 Land and Land Rights 549.594 -
87 390 Structures and Improvements 6.249.192 184,589
88 391 Office Furniture and Equipment 721.445 180.948
89 392 Transportation Equipment 19.967.763 2,338,185
90 393 Stores Equipment 129.543 -
91 394 Tools,Shop and Garage Equipment 2,661,937 504.905
92 395 Laboratory Equipment 920.471 53.520
93 396 Power Operated Equipment 9,233,274 44.484
94 397 Communication Equipment 13,815,593 1,113,791
95 398 Miscellaneous Equipment 85,661 7,870
96 SUBTOTAL Total of lines 86 through 95 54.334.473 4,428,292
97 399 Other Tangible Property
98 399.1 Asset Retirement Costs for General Plant
99 TOTAL General Plant Total of lines 96,97 and 98 54,334,473 4.428,292
100 TOTAL Accounts 101 and 106 1,828,433.012 115.371,984
101 102 Electric Plant Purchased
102 102 Less Electric Plant Sold
103 103 Experimental Plant Unclassified
104 TOTAL Electric Plant in Service(Total of lines 100 through 103 1.828.433,012 115.371,984
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.206-207

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation XO An Original mm/dd/yyyy End of 2024/Q4
0 A Resubmission 4/18/2025
ELECTRIC PLANT IN SERVICE-IDAHO(Account 101,102,103 and 106)(Continued)
Balance Line
Retirements Adjustments Transfers End of Year No.
(d) (a) (f) (g)
47
259,326 35,429) 10,470.185 48
- 533,282 13,858.008 49
3,340,137 11,823,565 142,155,298 50
1,211 7,691 5,985,789 51
565,527 (8,182,7221 139.349,705 52
32.676 (1,924,413) 67,660.843 53
90.035) 1,298,985 54
(113,334 2.510.907 55
(8,220) 917,504 56
57
4,198,877 21.652.107) 384.207,224 58
59
2,639,260) 4.734.302 60
186.838 1.825 8,749,662 61
623,234 150,201 62,619.503 62
63
465.219 209,560,220 64
53,405 146,033,583 65
22.287 2 62.687,973 66
61.841 104,310,661 67
22,381 114,691,748 68
15,317 1) 84,040.442 69
181,954 - 24,818.307 70
71
72
43.437 2 29.876,665 73
74
1,675,913 2.487.239 852,123,066 75
76
- 77
78
79
- 80
- 81
82
83
- - 84
85
3,878 553.472 86
11.030 65,126 6,487.877 87
67.118 14.784 850.059 88
509,633 181.599 21,977,914 89
- 2,683 132,226 90
80.311 45.886 3,132,417 91
33,800 18,312 958.503 92
756,013 34,162 8,555,907 93
938,575 308,231 13,682,578 94
14,912 2,356 80,975 95
2,411,392 60,555 56.411,928 96
97
- 98
2,411,392 60,555 56,411,928 99
10,081.835 40,581,732) 1,893,141.429 100
101
102
103
10,081,835 40,581,732) 1,893,141.429 104
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61405) E.ID_206-207

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation XK An Original mm/dd/yyyy End of 2024/Q4
❑ A Resubmission 4/18/2025
ELECTRIC OPERATING REVENUES-IDAHO
Instructions
1. Report below operating revenues attributable to the state of Idaho for each prescribed account in accordance with jurisdictional Results of
Operations. Report the portion of total operating revenue and megawatt hours which pertains to unbilled revenue and MWH pertaining unbilled
revenue in the lines provided.
2. Report number of customers(columns(f)and(g))on the basis of meters,in addition to the number of flat rate accounts;except that where separate
meter readings are added for billing purposes,one customer should be counted for each group of meters added. The average number of customers
means the average of twelve figures at the close of each month.
3. If increases or decreases from previous period(columns(c),(e),and(g))are not derived from previously reported figures,explain any inconsistencies
in a footnote in the available space at the bottom of the page,or in a separate schedule.
Line ELECTRIC OPERATING REVENUE
No. Account Current Year Prior Year
(a) (b) (c)
1 Sales of Electricity
2 440 Residential Sales 157,667,105 137.966.223
3 442 Commercial and Industrial Sales (3
4 Small or Commercial) 101.501,374 92.845.693
5 Large(or Industrial) 62.625.761 54.423,619
6 444 Public Street and Highway Lighting 3.182,224 9844790
7 445 Other Sales to Public Authorities
8 446 Sales to Railroads and Railways _
9 448 Interdepartmental Sales 269,072 251.933
10 ITOTAL Sales to Ultimate Customers (1) 325,245,537 288.332.258
11 447 Sales for Resale 80,559,611 90.099,322
12 TOTAL Sales of Electricity 405,805.148 378.431.580
13 449 1 (Less)Provision for Rate Refunds
14 TOTAL Revenues Net of Provision for Refunds 405,805.148 378.431.580
15 Other Operating Revenues
16 450 Forfeited Discounts _
17 451 Miscellaneous Service Revenues 118.514 85.026
18 453 Sales of Water and Water Power 204.222 244.496
19 454 Rent from Electric Property 2.685.677 3,267,433
20 455 Interdepartmental Rents
21 456 Other Electric Revenues (4) 18.223.740 1,615.551)
22 456.1 Revenues from Transmission of Electricitv for Others 12,485.059 11.000.538
23 457.1 Regional Control Service Revenues _
24 457.2 Miscellaneous Revenues _
25
26 TOTAL Other Operating Revenues 33.717213 12.981.942
27 TOTAL Electric Operating Revenues 439.522.361 391,413,522
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.300-301

e
Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation XD An Original mm/dd/yyyy End of 2024/Q4
-1 A Resubmission 4/18/2025
ELECTRIC OPERATING REVENUES-IDAHO
Instructions
4. Disclose amounts of$250,000 or greater in a footnote at the bottom of the page or in a separate schedule for accounts 451,456,and 457.2.
5. Commercial and Industrial Sales,Account 442,may be classified according to the basis of classification(Small or Commercial,and Large or Industrial)
regularly used by the respondent if such basis of classification is not generally greater than 1000 Kw of demand. (See Account 442 of the Uniform
System of Accounts. Explain basis of classification in a footnote.)
6. See pages 108-109 in the FERC Form 1, Important Changes During Period,for important new territory added and important rate increases or
decreases.
7. Include unmetered sales. Provide details of such Sales in a footnote in the available space at the bottom of this page or in a separate schedule.
MEGAWATT HOURS SOLD AVG.NO.OF CUSTOMERS PER MONTH Line
Current Year Previous Year Current Year Previous Year No.
(d) (e) M (g)
1
1,356.559 1,355,967 126.959 125,057 2
3
1.037.998 1,033,272 19,117 18,934 4
1,127,955 1,169.757 359 364 5
6.970 6.816 199 187 6
7
8
2,689 2.764 54 50 9
2 3,532.171 3,568,576 1 146.689 144,592 10
1,320.325 1.250.834 11
4,852,496 4,819.410 146,689 144,592 12
13
4,852,496 4,819,410 146,689 144,592 14
(1)Includes ($1,329,819) of unbilled revenues.
(2)Includes (14,211) MWH relating to unbilled revenues.
(3)Segregation of Commercial and Industrial made on basis of utilization of energy and not on size of account.
(4)Includes $ 62,791 associated with a special contract for wheeling over the distribution system on file with the IPUC,recorded
in sub-account 456700.
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.300-301

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation X❑ An Original mm/dd/yyyy End of 2024/Q4
❑ A Resubmission 4/18/2025
ELECTRIC OPERATION AND MAINTENANCE EXPENSES-IDAHO
Instructions
1. For each prescribed account below,report operation and maintenance expenses as allocated by the Results of Operations model to the state of
Idaho.
2. If the amount for previous year is not derived from previously reported figures,explain in a footnote.
Line Amount for Amount for
No. Account Current Year Previous Year
(a) (b) (c)
1 1.POWER PRODUCTION EXPENSES
2 A.Steam Power Generation
3 Operation
4 500 Operation Supervision and Engineering 73.768 62.923
5 501 Fuel 14,623,820 16.357,776
6 502 Steam Expenses 1.373.023 1,499,649
7 503 Steam from Other Sources 9,654
8 504 Less Steam Transferred-Cr.
9 505 Electric Expenses 273.850 267,873
10 506 Miscellaneous Steam Power Expenses 2.179.170 2,290,138
11 507 Rents
12 509 Allowances 1,012,939 662,437
13 TOTAL Operation Total of lines 4 through 12 19,546,224 21,140,796
14 iMaintenance
15 510 Maintenance Supervision and Engineering 179.781 145,172
16 511 Maintenance of Structures 356,284 308.807
17 512 Maintenance of Boiler Plant 3,385,599 2,518,387
18 513 Maintenance of Electric Plant 1,036,149 301,701
19 514 Maintenance of Miscellaneous Steam Plant 682.988 477.934
20 TOTAL Maintenance(Total of Lines 15 throw h 19) 5,640,801 3.752.001
21 ITOTAL Steam Power Generation Expenses(Total lines 13&20) 25,187,025 24,892,797
22 B.Nuclear Power Generation
23 Operation
24 517 Operation Supervision and Engineering
25 518 Fuel
26 519 Coolants and Water
27 520 Steam Expenses
28 521 Steam from Other Sources
29 522 Less Steam Transferred-Cr.
30 523 Electric Expenses
31 524 Miscellaneous Nuclear Power Expenses _
32 525 Rents _
33 TOTAL Operation(Total of lines 24 through 32
34 iMaintenance
35 528 Maintenance Supervision and Engineering
36 529 Maintenance of Structures
37 530 Maintenance of Reactor Plant Equipment
38 531 Maintenance of Electric Plant _
39 532 Maintenance of Miscellaneous Nuclear Plant
40 TOTAL Maintenance Total of lines 35 through 39 _
41 1 TOTAL Nuclear Power Generation Expenses(Total lines 33&40) - -
42 C.Hydraulic Power Generation
43 Operation
44 535 Operation Supervision and Engineering 963,068 873,540
45 536 Water for Power 409.184 420.762
46 537 Hydraulic Expenses 3,598,302 3.430,590
47 538 Electric Expenses 2,364,155 2,354,819
48 1 539 Miscellaneous Hydraulic Power Generation Expenses 469,073 782,614
49 1 540 Rents 2,689,672 2.708.276
50 TOTAL Operation Total of lines 44 through 49) 10.493.454 10.570,601
51 Maintenance
52 541 Maintenance Supervision and Engineering 155.136 253,624
53 542 Maintenance of Structures 111.095 176.918
54 543 Maintenance of Reservoirs,Dams,and Waterways 88,076 176,724
55 544 Maintenance of Electric Plant 996,169 1,111,088
L58
545 Maintenance of Miscellaneous H draulic Plant 226,540 235.635
TOTAL Maintenance Total of lines 53 throw h 57) 1.577,016 1,953,989
TOTAL H draulic Power Generation Ex enses Total of lines 50&58) 12.070,470 12,524,590
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E ID.320

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation X❑ An Original mm/dd/yyyy End of 2024/Q4
❑ A Resubmission 4/18/2025
ELECTRIC OPERATION AND MAINTENANCE EXPENSES-IDAHO
Instructions
1. For each prescribed account below,report operation and maintenance expenses as allocated by the Results of Operations model to the state of
Idaho.
2. If the amount for previous year is not derived from previously reported figures,explain in a footnote.
Line Amount for Amount for
No. Account Current Year Previous Year
(al (b) �)
60 1 D.Other Power Generation
61 loperation
62 1 546 Operation Supervision and Engineering 184,671 317.507
63 547 Fuel 38,762,668 41,283,882
64 548 Generation Expenses 1,800.315 1,385,197
65 549 Miscellaneous Other Power Generation Expenses 495,503 335,762
66 550 Rents 26,638 36,623
67 TOTAL Operation Total of lines 62 through 66) 41,269,795 43,358,971
68 Maintenance
69 551 Maintenance Supervision and Engineering 263,694 273,010
70 552 Maintenance of Structures 45,668 49.370
71 j 553 Maintenance of Generating and Electric Plant 978,538 714.808
72 1 554 Maintenance of Miscellaneous Other Power Generation Plant 309.898 306,276
73 ITOTAL Maintenance(Total of lines 69 through 72) 1.597,798 1.343,464
74 TOTAL Other Power Generation Expenses 42.867.593 44.702,435
75 E.Other Power Supply Expenses
76 555 Purchased Power 96,737,164 83,602,959
77 556 System Control and Load Dispatching 334,933 271,609
78 557 Other Expenses 32,627,724 22,732.536
79 TOTAL Other Power Supply Expenses(Total of lines 76 through 78) 129,699,821 106,607.104
80 1TOTAL Power Production Expenses(Total of lines 21.41,59,74.&79) 209,824,909 188,726,926
81 12,TRANSMISSION EXPENSES
82 Operation
83 560 Operation Supervision and Engineering 823,577 740,439
84 561 Load Dispatching 1.023,081 1.094,056
85 561.1 Load Dis patch-Reliability
86 561,2 Load Dispatch-Monitor and Operation Transmission System
87 561 3 Load Dispatch-Transmission Service and Scheduling
88 561 A Scheduling,System Control and Dispatch Services
89 561.5 Reliability,Planning and Standards Development
90 561.6 Transmission Service Studies
91 561.7 Generation Interconnection Studies
92 561 8 Reliability,Planning and Standards Development Services
93 562 Station Expenses 125,746 141,091
94 563 Overhead Lines Expenses 191,718 115,388
95 564 Underground Lines Expenses
96 565 Transmission of Electricity by Others 7.861.191 6,771.333
97 566 Miscellaneous Transmission Expenses 1,491,547 1.507,004
98 567 Rents 30.991 34,749
99 TOTAL Operation(Total of lines 83 through 98 11,547,851 10,404,060
100 Maintenance
101 568 Maintenance Supervision and Engineering 134,213 132.144
1021 569 Maintenance of Structures 155,769 221,141
1031 569.1 Maintenance of Computer Hardware
104 569.2 Maintenance of Computer Software
105 569.3 Maintenance of Communication Equipment
106 569.4 Maintenance of Miscellaneous Regional Transmission Plant
107 570 Maintenance of Station Equipment 207.411 412.330
108 571 Maintenance of Overhead Lines 672,067 784,099
109 572 Maintenance of Underground Lines 7,133 343
110 573 Maintenance of Miscellaneous Transmission Plant 42.751 23,890
111 ITOTAL Maintenance Total of lines 101 through 110) 1,219,344 1,573,947
112 ITOTAL Transmission Expenses Total of lines 99 and 111) i2.767,195 11.978,007
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.321

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation XX An Original mm/dd/yyyy End of 2024/Q4
A Resubmission 4/18/2025
ELECTRIC OPERATION AND MAINTENANCE EXPENSES-IDAHO
Instructions
1. For each prescribed account below,report operation and maintenance expenses as allocated by the Results of Operations model to the state of
Idaho.
2. If the amount for previous year is not derived from previously reported figures,explain in a footnote.
Line Amount for Amount for
No. Account Current Year Previous Year
113 3.REGIONAL MARKET EXPENSES
114 Operation
115 575.1 Operation Supervision _
1161 575.2 Day-Ahead and Real-Time Market Facilitation
1171 575.3 Transmission Rights Market Facilitation
1181 575.4 Capacity Market Facilitation _ _
1191 575.5 Ancillary Services Market Facilitation
120 575.6 Market Monitoring and Compliance
1211 575.7 Market Facilitation,Monitoring,and Compliance Services
1221 575.8 Rents _
123 JTotal Operation Total lines 115 through 122
124 1 Maintenance
125 576.1 Maintenance of Structures and Improvements
126 576.2 Maintenance of Computer Hardware
127 576.3 Maintenance of Computer Software
128 576.4 Maintenance of Communication Equipment
_
129 576.5 Maintenance of Miscellaneous Market Operation Plant
130 1 Total Maintenance Total lines 125 through 129
131 ITOTAL Regional Market Expenses Total lines 123&130)
13214.DISTRIBUTION EXPENSES
133 1 Operation
1341 580 Operation Supervision and Engineering 1,227,574 1,232,095
135 581 Load Dispatching
136 582 Station Expenses 300,279 316.065
137 583 Overhead Line Expenses 947,756 1.051.705
138 584 Underground Line Expenses 1,039.374 1,029.933
139 585 Street Lighting and Signal System Expenses 222
140 586 Meter Expenses 473,168 332,041
1411 587 Customer Installations Expenses 292,098 292.382
142 588 Miscellaneous Expenses 2.781.145 2.477,386
143 589 Rents 89,164 78.642
144 TOTAL Operation(Total of lines 134 through 143 7,150.558 6.810.471
145 Maintenance
146 590 Maintenance Supervision and Engineering 458.983 420,146
147 591 Maintenance of Structures 103,549 146,414
1481 592 Maintenance of Station Equipment 264.289 283.674
1491 593 Maintenance of Overhead Lines 9,501.399 8,713,113
1501 594 Maintenance of Underground Lines 252,388 236.566
151 595 Maintenance of Line Transformers 84,806 92.267
152 596 Maintenance of Street Lighting and Signal Systems 7.898 11,350
153 597 Maintenance of Meters 2.960 6,725
154 598 Maintenance of Miscellaneous Distribution Plant 265,803 303,008
155 TOTAL Maintenance Total lines 146 through 154 10,942,075 10.213.263
156 TOTAL Distribution Expenses Total of lines 144 and 155 18.092.633 17.023,734
157.5.CUSTOMER ACCOUNTS EXPENSES
158 Operation
159 901 Supervision 50.272 47.578
160 902 Meter Reading Expenses 204.515 212,114
161 903 Customer Records and Collection Expenses 3,333,021 3,084,888
162 904 Uncollectable Accounts 1,298,105 635.851
163 905 Miscellaneous Customer Accounts Expenses 65,091 97,575
164 ITOTAL Customer Accounts Expenses Total of line 159 through 163 4.951,004 4,078,006
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.322

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation XX An Original mm/dd/yyyy End of 2024/Q4
i
0 A Resubmission 4/18/2025
ELECTRIC OPERATION AND MAINTENANCE EXPENSES-IDAHO
Instructions
1. For each prescribed account below,report operation and maintenance expenses as allocated by the Results of Operations model to the state of
Idaho.
2. If the amount for previous year is not derived from previously reported figures,explain in a footnote.
Line Amount for Amount for
No. Account Current Year Previous Year
(a) (b) (c)
165 6.CUSTOMER SERVICE AND INFORMATIONAL EXPENSES
166 Operation
167 907 Supervision
168 908 Customer Assistance Expenses 4,211,825 6,636.366
169 909 Informational and Instructional Expenses 265.112 274,182
170 910 Miscellaneous Customer Service and Informational Expenses 21,993 80,482
171 TOTAL Customer Service and Informational Expenses Total lines 167 through 170 4.498.930 6,991,030
172 7.SALES EXPENSES
173 Operation
1741 911 Supervision
1751 912 Demonstrating and Selling Expenses
176 913 Advertising Expenses
177 916 Miscellaneous Sales Expenses
178 TOTAL Sales Expenses(Total of lines 174 through 177 -
179 8.ADMINISTRATIVE AND GENERAL EXPENSES
180 Operation
181 920 Administrative and General Salaries 10.649.677 10,502,009
182 921 Office Supplies and Expenses 1,253,489 1,229,331
183 922 Less Administrative Expenses Transferred-Credit 36,432 35,685
184 923 Outside Services Employed 4,687,026 4,179,887
185 924 Property Insurance 999.554 878,413
186 925 Injuries and Damages 7,048.750 3.451,813
187 926 Employee Pensions and Benefits 9,869,104 8.672,765
188 927 Franchise Requirements 1,231 1,200
1891 928 Regulatory Commission Expenses 2,492,361 2.535,519
1901 929 (Less)Duplicate Charges-Cr. -
191 930.1 General Advertising Expenses
192 930.2 Miscellaneous General Expenses 1,779,681 1.734,342
193 931 Rents 328,003 304,726
194 TOTAL Operation Total of lines 181 through 193 39.072.444 33,454,320
195 Maintenance
196 935 Maintenance of General Plant 4,643,859 4,480,241
197 TOTAL Administrative and General Expenses Total of lines 194 and 196 43,716.303 37,934,561
198 TOTAL Elec Op and Maint Expns(Total lines 80,112,131,156. 164, 171, 178, 197) 293,850,974 266,732.264
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.323

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation XD An Original mm/dd/yyyy End of 2024 I Q4
A Resubmission 4/18/2025
TRANSMISSION LINE STATISTICS-IDAHO
Instructions
1 Report information concerning transmission lines physically located in the state of Idaho,including the cost of lines,and expenses for the
year. List each transmission line having nominal voltage of 132 kilovolts or greater.
Transmission lines below this voltage should be grouped and totals reported for each group.
2. Transmission lines include all lines covered by the definition of transmission system plant as given in the Uniform System of Accounts. Do not report
substation costs and expenses on this page.
3. Report data by individual lines for all voltages if so required by the State commission.
4. Exclude from this page any transmission lines for which plant costs are included in Account 121,Nonutility Property.
5. Indicate whether the type of supporting structure reported in column(e)is:(1)single pole wood or steel;(2)H-frame wood,or steel poles;(3)tower;or
(4)underground construction. If a transmission line has more than one type of supporting structure,indicate the mileage of each type of construction
by the use of brackets and extra lines. Minor portions of a transmission line of a different type of construction need not be distinguished from the
remainder of the line.
6. Report in columns(f)and(g)the total pole miles of each transmission line. Show in column(f)the pole miles of line on structures the cost of which is
reported for the line designated;conversely,show in column(g)the pole miles of line on structures the cost of which is reported for another line. Report
pole miles of line on leased or partly-owned structures in column(g). In a footnote in the available space at the bottom of this page or in a separate
VOLTAGE(KV) LENGTH(Pole Miles)
Line DESIGNATION Indicate where other than Type of For underground lines.report circuit miles Number
No 60 cycle,3 phase Supporting On Structure On Structures of
From To Operating Designed Structure of Line Designated of Another Line Circuits
(a) (b) (c) (d) (e) (f) (g) (h)
1 Group Sum-115kV 115.00 115.00 59300
2
3 Beacon Cabinet Gore Plant 230.00 230.00 Steel Tower 1.00 1
4 Beacon Cabinet Gorge Plant 230.00 230.00 Steel Pale 19.00 2
5 Beacon Cabinet Gorae Plant 230.00 230.00 H Type 52.00 1
6
7 Divide Creek Lolo Sub 230.00 230.00 H Type 10.00 1
8 Divide Creek Lolo Sub 230.00 230.00 H Type 33.00 1
9 Noxon Plant Pine Creek Sub 230.00 230.00 Steel Pole 15.00 1
10 Noxon Plant Pine Creek Sub 230.00 230.00 H Type 1.00 1
11 Noxon Plant Pine Creek Sub 230.00 230.00 H Type 14.00 1
12 Cabinet Gorge Plant Noxon 230.00 230.00 H Type 2.00 1
13
14 Benewah Sw.Station Pine Creek Sub 230.00 230.00 H Type 43.00 1
15
16 Beacon Sub Lolo Sub 230.00 230.00 Steel Pole 10.00 2
17 Beacon Sub Lolo Sub 230.00 230.00 H Type 63.00 1
18 Beacon Sub Lolo Sub 230.00 230.00 H Type 8.00 1
19
20 North Lewiston Walla Walla 230.00 23000 H Type 8.00 1
21
22 North Lewiston Shawnee 230.00 23000 H-Type 1.00 1
23
24 Hatwai N.Lewiston Sub 230.00 23000 H Type 7.00 1
25
26
27
28
29
30
31
32
33
34
35
36
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E.ID.422-423

Name of Respondent This Report is: Date of Report Year/Period of Report
Avista Corporation X� An Original mm/dd/yyyy End of 2024/Q4
Q A Resubmission 4/18/2026
TRANSMISSION LINE STATISTICS-IDAHO
Instructions
schedule,explain the basis of such occupancy and state whether these expenses with respect to such structures are included in the expenses reported
for the line designated.
7. Do not report the same transmission line structure twice. Report lower-voltage lines and h'.gher-voltage lines as one line. Designate in a footnote if you
do not have include lower-voltage lines with higher-voltage lines. If two or more transmission line structures support lines of the same voltage,report the
pole miles of the primary structure in column(f)and the pole miles of the other line(s)in column(g).
8. Designate any transmission line or portion thereof for which the respondent is not the sole owner. If such property is leased from another company,give
name of lessor,date and terms of lease,and amount of rent for year. For any transmission line other than a leased Irne,or portion thereof,for which the
respondent is not the sole owner but which the respondent operates or shares in the operation of,furnish a succinct statement explaining the arrangement
and giving details of such matters as percent ownership by respondent in the line,name of c-owner,basis of sharing expenses of the line,and and how
expenses borne by the respondent are accounts for,and accounts affected. Specify whether lessor,co-owner,or other party is an associated company.
9. Designate any transmission line leased to another company and give name of lessee,date and terms of lease,annual rent for year,and how determined.
Specify whether lessee is an associated company.
10. Base the plant cost figures called for in columns Q)through(1)on the book cost at end of year associated with the physical lines reported.
COST OF LINE EXPENSES,EXCEPT DEPRECIATION AND TAXES
Size of Include N column land,land hls,and cfearing ht-of-wayLine
Conductor Construction Operation Maintenance Total No.
and Material Land and Other Costs Total Cost Expenses Expenses Rents Expenses
O) U) (k) (I) (m) (n) (o) (p)
5,349.153 137.462.966 142,812,119 494.406 522,044 1,016.450 1
2
1590 ACSS 3
4
1590 ACSS
1590 ACSR 1.042,786 25.465,727 26,508,513 1,207 1,207 5
6
1590 ACSR 7
1272 AAC 169,117 21.627,264 21.796,381 4,522 1,995 6,517 8
1272 ACSR - 9
1590 ACS 10
954 AAC 694,233 12.400,022 13,094,255 461 7,540 8,001 11
954 AAC 138.327 1,077,444 1,215,771 52.262 52.262 12
13
954 AAC 399.821 5,524,153 5,923,974 64,208 15.629 79.837 14
15
1590 ACSS 16
1272 AAC 17
1272 ACSS 104,278 31,265.113 31,369,391 11.481 11,481 18
19
1272 AAC 25,818 1,128.365 1,154,183 20
21
1272 ACSR 10,015 316,837 326.852 22
23
1590 ACSR 155.244 2,221.191 2,376,435 24
25
26
27
28
29
30
31
32
33
34
35
36
IDAHO STATE ELECTRIC ANNUAL REPORT(IC 61-405) E-ID.422-423