20231228Exhibit 5.pdf

Intermountain Gas Company
Avoided Cost Model
2023 – 2028
Exhibit No. 5
Line Nominal Cost Real Percent Real Cost Present Avoided Cost
No.Year
(a)(b)(c)(d)(e)(f)
1 2023 1.38$ 1.38$ 1.33$ 1.38$
2 2024 0.83 -41.53%0.80 2.08 1.10
3 2025 0.76 -10.69%0.72 2.73 0.97
4 2026 0.73 -7.15%0.67 3.31 0.90
5 2027 0.68 -9.91%0.60 3.82 0.85
6 2028 0.66 -5.39%0.57 4.28 0.80
7 2029 0.69 0.05%0.57 4.73 0.77
8 2030 0.71 0.19%0.57 5.16 0.75
9 2031 0.73 -0.48%0.57 5.57 0.73
10 2032 0.76 1.84%0.58 5.98 0.72
11 2033 0.80 1.88%0.59 6.39 0.71
12 2034 0.84 1.06%0.59 6.78 0.70
13 2035 0.86 -0.11%0.59 7.16 0.70
14 2036 0.89 -0.34%0.59 7.52 0.69
15 2037 0.91 -0.24%0.59 7.88 0.68
16 2038 0.94 -0.13%0.59 8.22 0.68
17 2039 0.98 0.63%0.59 8.55 0.68
18 2040 1.03 2.13%0.61 8.87 0.67
19 2041 1.10 3.32%0.63 9.20 0.67
20 2042 1.15 1.62%0.64 9.52 0.67
21 2043 1.18 -0.35%0.63 9.82 0.67
22 2044 1.22 0.54%0.64 10.12 0.67
23 2045 1.27 0.54%0.64 10.41 0.67
24 2046 1.32 0.54%0.64 10.70 0.67
25 2047 1.36 0.55%0.65 10.97 0.67
26 2048 1.42 0.55%0.65 11.23 0.67
27 2049 1.47 0.55%0.66 11.49 0.67
28 2050 1.52 0.55%0.66 11.74 0.67
29 2051 1.58 0.55%0.66 11.99 0.67
30 2052 1.64 0.55%0.67 12.22 0.67
Page 11, Line 4, Column (b).
Page 11, Line 5, Column (b).
INTERMOUNTAIN GAS COMPANY
Avoided Cost by Year
NOTES
2
Line Commodity Transportation Total
No.Year
(a)(b)(c)(d)(e)
1 2023 1.18$ -$ 0.20$ 1.38$
2 2024 0.62 - 0.21 0.83
3 2025 0.55 - 0.21 0.76
4 2026 0.51 - 0.22 0.73
5 2027 0.45 - 0.23 0.68
6 2028 0.43 - 0.23 0.66
7 2029 0.44 - 0.24 0.69
8 2030 0.46 - 0.25 0.71
9 2031 0.47 - 0.26 0.73
10 2032 0.50 - 0.27 0.76
11 2033 0.53 - 0.27 0.80
12 2034 0.55 - 0.28 0.84
13 2035 0.57 - 0.29 0.86
14 2036 0.59 - 0.30 0.89
15 2037 0.60 - 0.31 0.91
16 2038 0.62 - 0.32 0.94
17 2039 0.65 - 0.33 0.98
18 2040 0.69 - 0.34 1.03
19 2041 0.74 - 0.35 1.10
20 2042 0.79 - 0.36 1.15
21 2043 0.81 - 0.37 1.18
22 2044 0.84 - 0.39 1.22
23 2045 0.87 - 0.40 1.27
24 2046 0.91 - 0.41 1.32
25 2047 0.94 - 0.42 1.36
26 2048 0.98 - 0.44 1.42
27 2049 1.02 - 0.45 1.47
28 2050 1.06 - 0.46 1.52
29 2051 1.10 - 0.48 1.58
30 2052 1.14 - 0.49 1.64
to therms.
from Page 11, Line 4, Column (b).
INTERMOUNTAIN GAS COMPANY
Nominal Avoided Cost by Year
NOTES
3
Line Heating Weighted Basin HDD HDD Commodity
No.Year Month
(a)(b)(c)(d)(e)(f)
1 2023 10 5.53$ 3%0.18$
2 2023 11 5.91 8%0.48
3 2023 12 14.21 16%2.23
4 2023 1 27.73 19%5.32
5 2023 2 14.40 16%2.33
6 2023 3 4.24 15%0.66
7 2023 4 2.57 10%0.26
8 2023 5 2.31 7%0.16
9 2023 6 2.39 4%0.08
10 2023 7 3.06 1%0.03
11 2023 8 3.45 0%0.00
12 2023 9 3.05 1%0.02 11.75$
13 2024 10 2.91 3%0.09
14 2024 11 5.11 8%0.42
15 2024 12 8.26 16%1.30
16 2024 1 8.59 19%1.65
17 2024 2 7.76 16%1.26
18 2024 3 4.64 15%0.72
19 2024 4 2.78 10%0.28
20 2024 5 2.68 7%0.19
21 2024 6 2.68 4%0.09
22 2024 7 3.13 1%0.03
23 2024 8 3.15 0%0.00
24 2024 9 3.11 1%0.02 6.04$
25 2025 10 3.11 3%0.10
26 2025 11 5.14 8%0.42
27 2025 12 6.74 16%1.06
28 2025 1 6.69 19%1.28
29 2025 2 6.20 16%1.00
30 2025 3 4.29 15%0.66
31 2025 4 2.92 10%0.29
32 2025 5 2.92 7%0.20
33 2025 6 2.90 4%0.10
34 2025 7 3.12 1%0.03
35 2025 8 3.19 0%0.00
36 2025 9 3.19 1%0.02 5.18$
INTERMOUNTAIN GAS COMPANY
Commodity Cost
NOTES
4
Line Heating Weighted Basin HDD HDD Commodity
No.Year Month
(a)(b)(c)(d)(e)(f)
1 2026 10 3.18$ 3%0.10$
2 2026 11 4.71 8%0.38
3 2026 12 5.83 16%0.91
4 2026 1 5.74 19%1.10
5 2026 2 5.33 16%0.86
6 2026 3 4.09 15%0.63
7 2026 4 2.99 10%0.30
8 2026 5 3.00 7%0.21
9 2026 6 3.01 4%0.11
10 2026 7 3.19 1%0.03
11 2026 8 3.18 0%0.00
12 2026 9 3.16 1%0.02 4.66$
13 2027 10 3.16 3%0.10
14 2027 11 3.99 8%0.32
15 2027 12 4.63 16%0.73
16 2027 1 4.53 19%0.87
17 2027 2 4.32 16%0.70
18 2027 3 3.82 15%0.59
19 2027 4 3.10 10%0.31
20 2027 5 3.13 7%0.22
21 2027 6 3.18 4%0.11
22 2027 7 3.19 1%0.03
23 2027 8 3.16 0%0.00
24 2027 9 3.12 1%0.02 4.00$
25 2028 10 3.15 3%0.10
26 2028 11 3.78 8%0.31
27 2028 12 4.06 16%0.64
28 2028 1 4.08 19%0.78
29 2028 2 3.78 16%0.61
30 2028 3 3.53 15%0.55
31 2028 4 3.10 10%0.31
32 2028 5 3.12 7%0.22
33 2028 6 3.14 4%0.11
34 2028 7 3.19 1%0.03
35 2028 8 3.15 0%0.00
36 2028 9 3.10 1%0.02 3.68$
INTERMOUNTAIN GAS COMPANY
Commodity Cost
NOTES
5
Line Heating Weighted Basin HDD HDD Commodity
No.Year Month
(a)(b)(c)(d)(e)(f)
1 2029 10 3.12$ 3%0.10$
2 2029 11 3.68 8%0.30
3 2029 12 4.03 16%0.63
4 2029 1 3.97 19%0.76
5 2029 2 3.82 16%0.62
6 2029 3 3.63 15%0.56
7 2029 4 3.18 10%0.32
8 2029 5 3.20 7%0.22
9 2029 6 3.22 4%0.11
10 2029 7 3.22 1%0.03
11 2029 8 3.19 0%0.00
12 2029 9 3.15 1%0.02 3.68$
13 2030 10 3.19 3%0.10
14 2030 11 3.76 8%0.31
15 2030 12 4.05 16%0.64
16 2030 1 3.90 19%0.75
17 2030 2 3.58 16%0.58
18 2030 3 3.60 15%0.56
19 2030 4 3.42 10%0.34
20 2030 5 3.44 7%0.24
21 2030 6 3.57 4%0.13
22 2030 7 3.48 1%0.03
23 2030 8 3.24 0%0.00
24 2030 9 3.23 1%0.02 3.69$
25 2031 10 3.29 3%0.11
26 2031 11 3.68 8%0.30
27 2031 12 3.80 16%0.60
28 2031 1 3.78 19%0.73
29 2031 2 3.65 16%0.59
30 2031 3 3.69 15%0.57
31 2031 4 3.48 10%0.35
32 2031 5 3.48 7%0.24
33 2031 6 3.66 4%0.13
34 2031 7 3.57 1%0.03
35 2031 8 3.34 0%0.00
36 2031 9 3.28 1%0.02 3.66$
Commodity Cost
INTERMOUNTAIN GAS COMPANY
NOTES
6
Line Heating Weighted Basin HDD HDD Commodity
No.Year Month
(a)(b)(c)(d)(e)(f)
1 2032 10 3.29$ 3%0.11$
2 2032 11 3.71 8%0.30
3 2032 12 3.94 16%0.62
4 2032 1 3.88 19%0.74
5 2032 2 3.78 16%0.61
6 2032 3 3.79 15%0.59
7 2032 4 3.59 10%0.36
8 2032 5 3.59 7%0.25
9 2032 6 3.84 4%0.13
10 2032 7 3.72 1%0.03
11 2032 8 3.49 0%0.00
12 2032 9 3.40 1%0.02 3.77$
13 2033 10 3.38 3%0.11
14 2033 11 3.77 8%0.31
15 2033 12 4.04 16%0.63
16 2033 1 4.00 19%0.77
17 2033 2 3.90 16%0.63
18 2033 3 3.85 15%0.60
19 2033 4 3.73 10%0.37
20 2033 5 3.70 7%0.26
21 2033 6 3.98 4%0.14
22 2033 7 3.82 1%0.04
23 2033 8 3.60 0%0.00
24 2033 9 3.50 1%0.02 3.88$
25 2034 10 3.48 3%0.11
26 2034 11 3.88 8%0.32
27 2034 12 4.14 16%0.65
28 2034 1 4.06 19%0.78
29 2034 2 3.99 16%0.65
30 2034 3 3.96 15%0.61
31 2034 4 3.69 10%0.37
32 2034 5 3.66 7%0.25
33 2034 6 3.96 4%0.14
34 2034 7 3.79 1%0.04
35 2034 8 3.59 0%0.00
36 2034 9 3.49 1%0.02 3.94$
INTERMOUNTAIN GAS COMPANY
Commodity Cost
NOTES
7
Line Heating Weighted Basin HDD HDD Commodity
No.Year Month
(a)(b)(c)(d)(e)(f)
1 2035 10 3.43$ 3%0.11$
2 2035 11 3.84 8%0.31
3 2035 12 4.14 16%0.65
4 2035 1 4.07 19%0.78
5 2035 2 3.96 16%0.64
6 2035 3 3.93 15%0.61
7 2035 4 3.72 10%0.37
8 2035 5 3.69 7%0.26
9 2035 6 3.97 4%0.14
10 2035 7 3.81 1%0.04
11 2035 8 3.61 0%0.00
12 2035 9 3.52 1%0.02 3.93$
13 2036 10 3.47 3%0.11
14 2036 11 3.88 8%0.32
15 2036 12 4.16 16%0.65
16 2036 1 4.01 19%0.77
17 2036 2 3.92 16%0.63
18 2036 3 3.88 15%0.60
19 2036 4 3.72 10%0.37
20 2036 5 3.71 7%0.26
21 2036 6 3.94 4%0.14
22 2036 7 3.81 1%0.04
23 2036 8 3.60 0%0.00
24 2036 9 3.53 1%0.02 3.91$
25 2037 10 3.53 3%0.11
26 2037 11 3.88 8%0.32
27 2037 12 4.11 16%0.65
28 2037 1 3.96 19%0.76
29 2037 2 3.99 16%0.65
30 2037 3 3.87 15%0.60
31 2037 4 3.67 10%0.37
32 2037 5 3.67 7%0.25
33 2037 6 3.90 4%0.14
34 2037 7 3.77 1%0.04
35 2037 8 3.56 0%0.00
36 2037 9 3.47 1%0.02 3.90$
INTERMOUNTAIN GAS COMPANY
Commodity Cost
NOTES
8
Line Heating Weighted Basin HDD HDD Commodity
No.Year Month
(a)(b)(c)(d)(e)(f)
1 2038 10 3.48$ 3%0.11$
2 2038 11 3.83 8%0.31
3 2038 12 4.07 16%0.64
4 2038 1 3.92 19%0.75
5 2038 2 3.97 16%0.64
6 2038 3 3.91 15%0.61
7 2038 4 3.71 10%0.37
8 2038 5 3.72 7%0.26
9 2038 6 3.92 4%0.14
10 2038 7 3.79 1%0.04
11 2038 8 3.58 0%0.00
12 2038 9 3.52 1%0.02 3.89$
13 2039 10 3.56 3%0.12
14 2039 11 3.87 8%0.32
15 2039 12 4.10 16%0.64
16 2039 1 3.94 19%0.76
17 2039 2 3.95 16%0.64
18 2039 3 3.98 15%0.62
19 2039 4 3.78 10%0.38
20 2039 5 3.79 7%0.26
21 2039 6 3.97 4%0.14
22 2039 7 3.85 1%0.04
23 2039 8 3.65 0%0.00
24 2039 9 3.60 1%0.02 3.93$
25 2040 10 3.65 3%0.12
26 2040 11 3.98 8%0.32
27 2040 12 4.22 16%0.66
28 2040 1 4.08 19%0.78
29 2040 2 4.12 16%0.67
30 2040 3 4.09 15%0.63
31 2040 4 3.89 10%0.39
32 2040 5 3.89 7%0.27
33 2040 6 4.14 4%0.15
34 2040 7 4.05 1%0.04
35 2040 8 3.84 0%0.00
36 2040 9 3.72 1%0.02 4.05$
NOTES
INTERMOUNTAIN GAS COMPANY
Commodity Cost
9
Line Heating Weighted Basin HDD HDD Commodity
No.Year Month
(a)(b)(c)(d)(e)(f)
1 2041 10 3.69$ 3%0.12$
2 2041 11 4.13 8%0.34
3 2041 12 4.47 16%0.70
4 2041 1 4.32 19%0.83
5 2041 2 4.35 16%0.71
6 2041 3 4.31 15%0.67
7 2041 4 4.01 10%0.40
8 2041 5 4.01 7%0.28
9 2041 6 4.31 4%0.15
10 2041 7 4.20 1%0.04
11 2041 8 3.98 0%0.00
12 2041 9 3.84 1%0.02 4.26$
13 2042 10 3.78 3%0.12
14 2042 11 4.23 8%0.34
15 2042 12 4.58 16%0.72
16 2042 1 4.43 19%0.85
17 2042 2 4.48 16%0.73
18 2042 3 4.45 15%0.69
19 2042 4 4.06 10%0.41
20 2042 5 4.06 7%0.28
21 2042 6 4.34 4%0.15
22 2042 7 4.25 1%0.04
23 2042 8 4.01 0%0.00
24 2042 9 3.88 1%0.02 4.36$
25 2043 10 3.83 3%0.12
26 2043 11 4.26 8%0.35
27 2043 12 4.57 16%0.72
28 2043 1 4.43 19%0.85
29 2043 2 4.44 16%0.72
30 2043 3 4.37 15%0.68
31 2043 4 4.03 10%0.40
32 2043 5 4.04 7%0.28
33 2043 6 4.34 4%0.15
34 2043 7 4.26 1%0.04
35 2043 8 4.01 0%0.00
36 2043 9 3.87 1%0.02 4.33$
INTERMOUNTAIN GAS COMPANY
Commodity Cost
NOTES
10
Line Combined
No.Description RS GS-1 RS and GS-1
(a)(b)(c)(d)
1
2
3 RS and GS-1 Combined Gas Transportation Cost per Therm 0.15776$
4
5
6 RS and GS-1 Combined Gas Transportation Cost per Therm 0.00467$
7 0.03862$
8 Total RS and GS-1 Combined Gas Transportation Cost per Therm 0.20105$
INTERMOUNTAIN GAS COMPANY
Avoided Gas Transportation Cost
NOTES
11
Line
No.Description Value Ratio Weighting W/Tax benefit
(a)(b)(c)(d)(e)
1
2
3 Weighted Average Cost of Capital 6.78%
4 Inflation Assumption 3.2%
5 Real Discount Rate 3.51%
NOTES
INTERMOUNTAIN GAS COMPANY
Discount Rate
12