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Leases | 12 Months Ended
--- | ---
Dec. 31, 2021
Leases [Line Items] |
Operating Leases | LEASES Operating Leases - Alliant Energy’s, IPL’s and WPL’s operating leases primarily include leases of space on telecommunication towers and leases of property. Operating lease details are as follows (dollars in millions):
| December 31, 2021 |  | December 31, 2020
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Property, plant and equipment, net | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Other current liabilities | $2 |  | $1 |  | $1 |  | $2 |  | $1 |  | $1
Other liabilities | 12 |  | 8 |  | 4 |  | 13 |  | 8 |  | 5
Total operating lease liabilities | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Weighted average remaining lease term | 9 years |  | 11 years |  | 8 years |  | 10 years |  | 11 years |  | 9 years
Weighted average discount rate | 4% |  | 4% |  | 4% |  | 4% |  | 4% |  | 4%
Finance Leases - WPL is currently leasing the Sheboygan Falls Energy Facility from AEF’s Non-utility Generation business through 2025, the initial lease term. WPL is responsible for the operation of the EGU and has exclusive rights to its output. This finance lease contains two lease renewal periods, which are not included in the finance lease obligation, as well as an option to purchase the facility at the end of the initial lease term. For Alliant Energy, the leased Sheboygan Falls Energy Facility is eliminated upon consolidation and is therefore is not reflected in Alliant Energy’s amounts below. Related to its investments in solar generation, WPL entered into land lease agreements with unaffiliated parties that commenced in 2021. The leases have various terms with optional renewal periods that are assumed to be extended through the end of the estimated useful lives of the solar generating facilities. The leases do not contain purchase options and are fixed lease payments. Finance lease details are as follows (dollars in millions):
| Alliant Energy |  | WPL
| December 31, 2021 |  | December 31, 2021 |  | December 31, 2020 |  |
Property, plant and equipment, net: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $21 |  | $27 |  |
Leased land for solar generation | $11 |  | 11 |  | — |  |
| $11 |  | $32 |  | $27 |  |
Other current liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $10 |  | $9 |  |
Leased land for solar generation | $1 |  | 1 |  | — |  |
| 1 |  | 11 |  | 9 |  |
Other liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | 31 |  | 42 |  |
Leased land for solar generation | 11 |  | 11 |  | — |  |
| 11 |  | 42 |  | 42 |  |
Total finance lease liabilities | $12 |  | $53 |  | $51 |  |
Weighted average remaining lease term | 34 years |  | 10 years |  | 4 years |  |
Weighted average discount rate | 3% |  | 9% |  | 11% |  |
| 2021 |  | 2021 |  | 2020 |  | 2019
Depreciation and amortization expenses | $— |  | $6 |  | $6 |  | $6
Interest expense | — |  | 5 |  | 6 |  | 7
Total finance lease expense | $— |  | $11 |  | $12 |  | $13
Expected Maturities - As of December 31, 2021, expected maturities of lease liabilities were as follows (in millions):
| 2022 |  | 2023 |  | 2024 |  | 2025 |  | 2026 |  | Thereafter |  | Total |  | Less: amount representing interest |  | Present value of minimum lease payments
Operating Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $7 |  | $17 |  | $3 |  | $14
IPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 6 |  | 11 |  | 2 |  | 9
WPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  | 6 |  | 1 |  | 5
Finance Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | — |  |  | — |  |  | — |  |  | — |  |  | 1 |  |  | 19 |  | 20 |  | 8 |  | 12
WPL | 15 |  |  | 15 |  |  | 15 |  |  | 6 |  |  | 1 |  |  | 19 |  | 71 |  | 18 |  | 53
Finance Leases | LEASES Operating Leases - Alliant Energy’s, IPL’s and WPL’s operating leases primarily include leases of space on telecommunication towers and leases of property. Operating lease details are as follows (dollars in millions):
| December 31, 2021 |  | December 31, 2020
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Property, plant and equipment, net | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Other current liabilities | $2 |  | $1 |  | $1 |  | $2 |  | $1 |  | $1
Other liabilities | 12 |  | 8 |  | 4 |  | 13 |  | 8 |  | 5
Total operating lease liabilities | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Weighted average remaining lease term | 9 years |  | 11 years |  | 8 years |  | 10 years |  | 11 years |  | 9 years
Weighted average discount rate | 4% |  | 4% |  | 4% |  | 4% |  | 4% |  | 4%
Finance Leases - WPL is currently leasing the Sheboygan Falls Energy Facility from AEF’s Non-utility Generation business through 2025, the initial lease term. WPL is responsible for the operation of the EGU and has exclusive rights to its output. This finance lease contains two lease renewal periods, which are not included in the finance lease obligation, as well as an option to purchase the facility at the end of the initial lease term. For Alliant Energy, the leased Sheboygan Falls Energy Facility is eliminated upon consolidation and is therefore is not reflected in Alliant Energy’s amounts below. Related to its investments in solar generation, WPL entered into land lease agreements with unaffiliated parties that commenced in 2021. The leases have various terms with optional renewal periods that are assumed to be extended through the end of the estimated useful lives of the solar generating facilities. The leases do not contain purchase options and are fixed lease payments. Finance lease details are as follows (dollars in millions):
| Alliant Energy |  | WPL
| December 31, 2021 |  | December 31, 2021 |  | December 31, 2020 |  |
Property, plant and equipment, net: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $21 |  | $27 |  |
Leased land for solar generation | $11 |  | 11 |  | — |  |
| $11 |  | $32 |  | $27 |  |
Other current liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $10 |  | $9 |  |
Leased land for solar generation | $1 |  | 1 |  | — |  |
| 1 |  | 11 |  | 9 |  |
Other liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | 31 |  | 42 |  |
Leased land for solar generation | 11 |  | 11 |  | — |  |
| 11 |  | 42 |  | 42 |  |
Total finance lease liabilities | $12 |  | $53 |  | $51 |  |
Weighted average remaining lease term | 34 years |  | 10 years |  | 4 years |  |
Weighted average discount rate | 3% |  | 9% |  | 11% |  |
| 2021 |  | 2021 |  | 2020 |  | 2019
Depreciation and amortization expenses | $— |  | $6 |  | $6 |  | $6
Interest expense | — |  | 5 |  | 6 |  | 7
Total finance lease expense | $— |  | $11 |  | $12 |  | $13
Expected Maturities - As of December 31, 2021, expected maturities of lease liabilities were as follows (in millions):
| 2022 |  | 2023 |  | 2024 |  | 2025 |  | 2026 |  | Thereafter |  | Total |  | Less: amount representing interest |  | Present value of minimum lease payments
Operating Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $7 |  | $17 |  | $3 |  | $14
IPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 6 |  | 11 |  | 2 |  | 9
WPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  | 6 |  | 1 |  | 5
Finance Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | — |  |  | — |  |  | — |  |  | — |  |  | 1 |  |  | 19 |  | 20 |  | 8 |  | 12
WPL | 15 |  |  | 15 |  |  | 15 |  |  | 6 |  |  | 1 |  |  | 19 |  | 71 |  | 18 |  | 53
IPL [Member] |
Leases [Line Items] |
Operating Leases | LEASES Operating Leases - Alliant Energy’s, IPL’s and WPL’s operating leases primarily include leases of space on telecommunication towers and leases of property. Operating lease details are as follows (dollars in millions):
| December 31, 2021 |  | December 31, 2020
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Property, plant and equipment, net | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Other current liabilities | $2 |  | $1 |  | $1 |  | $2 |  | $1 |  | $1
Other liabilities | 12 |  | 8 |  | 4 |  | 13 |  | 8 |  | 5
Total operating lease liabilities | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Weighted average remaining lease term | 9 years |  | 11 years |  | 8 years |  | 10 years |  | 11 years |  | 9 years
Weighted average discount rate | 4% |  | 4% |  | 4% |  | 4% |  | 4% |  | 4%
Finance Leases - WPL is currently leasing the Sheboygan Falls Energy Facility from AEF’s Non-utility Generation business through 2025, the initial lease term. WPL is responsible for the operation of the EGU and has exclusive rights to its output. This finance lease contains two lease renewal periods, which are not included in the finance lease obligation, as well as an option to purchase the facility at the end of the initial lease term. For Alliant Energy, the leased Sheboygan Falls Energy Facility is eliminated upon consolidation and is therefore is not reflected in Alliant Energy’s amounts below. Related to its investments in solar generation, WPL entered into land lease agreements with unaffiliated parties that commenced in 2021. The leases have various terms with optional renewal periods that are assumed to be extended through the end of the estimated useful lives of the solar generating facilities. The leases do not contain purchase options and are fixed lease payments. Finance lease details are as follows (dollars in millions):
| Alliant Energy |  | WPL
| December 31, 2021 |  | December 31, 2021 |  | December 31, 2020 |  |
Property, plant and equipment, net: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $21 |  | $27 |  |
Leased land for solar generation | $11 |  | 11 |  | — |  |
| $11 |  | $32 |  | $27 |  |
Other current liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $10 |  | $9 |  |
Leased land for solar generation | $1 |  | 1 |  | — |  |
| 1 |  | 11 |  | 9 |  |
Other liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | 31 |  | 42 |  |
Leased land for solar generation | 11 |  | 11 |  | — |  |
| 11 |  | 42 |  | 42 |  |
Total finance lease liabilities | $12 |  | $53 |  | $51 |  |
Weighted average remaining lease term | 34 years |  | 10 years |  | 4 years |  |
Weighted average discount rate | 3% |  | 9% |  | 11% |  |
| 2021 |  | 2021 |  | 2020 |  | 2019
Depreciation and amortization expenses | $— |  | $6 |  | $6 |  | $6
Interest expense | — |  | 5 |  | 6 |  | 7
Total finance lease expense | $— |  | $11 |  | $12 |  | $13
Expected Maturities - As of December 31, 2021, expected maturities of lease liabilities were as follows (in millions):
| 2022 |  | 2023 |  | 2024 |  | 2025 |  | 2026 |  | Thereafter |  | Total |  | Less: amount representing interest |  | Present value of minimum lease payments
Operating Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $7 |  | $17 |  | $3 |  | $14
IPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 6 |  | 11 |  | 2 |  | 9
WPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  | 6 |  | 1 |  | 5
Finance Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | — |  |  | — |  |  | — |  |  | — |  |  | 1 |  |  | 19 |  | 20 |  | 8 |  | 12
WPL | 15 |  |  | 15 |  |  | 15 |  |  | 6 |  |  | 1 |  |  | 19 |  | 71 |  | 18 |  | 53
WPL [Member] |
Leases [Line Items] |
Operating Leases | LEASES Operating Leases - Alliant Energy’s, IPL’s and WPL’s operating leases primarily include leases of space on telecommunication towers and leases of property. Operating lease details are as follows (dollars in millions):
| December 31, 2021 |  | December 31, 2020
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Property, plant and equipment, net | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Other current liabilities | $2 |  | $1 |  | $1 |  | $2 |  | $1 |  | $1
Other liabilities | 12 |  | 8 |  | 4 |  | 13 |  | 8 |  | 5
Total operating lease liabilities | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Weighted average remaining lease term | 9 years |  | 11 years |  | 8 years |  | 10 years |  | 11 years |  | 9 years
Weighted average discount rate | 4% |  | 4% |  | 4% |  | 4% |  | 4% |  | 4%
Finance Leases - WPL is currently leasing the Sheboygan Falls Energy Facility from AEF’s Non-utility Generation business through 2025, the initial lease term. WPL is responsible for the operation of the EGU and has exclusive rights to its output. This finance lease contains two lease renewal periods, which are not included in the finance lease obligation, as well as an option to purchase the facility at the end of the initial lease term. For Alliant Energy, the leased Sheboygan Falls Energy Facility is eliminated upon consolidation and is therefore is not reflected in Alliant Energy’s amounts below. Related to its investments in solar generation, WPL entered into land lease agreements with unaffiliated parties that commenced in 2021. The leases have various terms with optional renewal periods that are assumed to be extended through the end of the estimated useful lives of the solar generating facilities. The leases do not contain purchase options and are fixed lease payments. Finance lease details are as follows (dollars in millions):
| Alliant Energy |  | WPL
| December 31, 2021 |  | December 31, 2021 |  | December 31, 2020 |  |
Property, plant and equipment, net: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $21 |  | $27 |  |
Leased land for solar generation | $11 |  | 11 |  | — |  |
| $11 |  | $32 |  | $27 |  |
Other current liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $10 |  | $9 |  |
Leased land for solar generation | $1 |  | 1 |  | — |  |
| 1 |  | 11 |  | 9 |  |
Other liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | 31 |  | 42 |  |
Leased land for solar generation | 11 |  | 11 |  | — |  |
| 11 |  | 42 |  | 42 |  |
Total finance lease liabilities | $12 |  | $53 |  | $51 |  |
Weighted average remaining lease term | 34 years |  | 10 years |  | 4 years |  |
Weighted average discount rate | 3% |  | 9% |  | 11% |  |
| 2021 |  | 2021 |  | 2020 |  | 2019
Depreciation and amortization expenses | $— |  | $6 |  | $6 |  | $6
Interest expense | — |  | 5 |  | 6 |  | 7
Total finance lease expense | $— |  | $11 |  | $12 |  | $13
Expected Maturities - As of December 31, 2021, expected maturities of lease liabilities were as follows (in millions):
| 2022 |  | 2023 |  | 2024 |  | 2025 |  | 2026 |  | Thereafter |  | Total |  | Less: amount representing interest |  | Present value of minimum lease payments
Operating Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $7 |  | $17 |  | $3 |  | $14
IPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 6 |  | 11 |  | 2 |  | 9
WPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  | 6 |  | 1 |  | 5
Finance Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | — |  |  | — |  |  | — |  |  | — |  |  | 1 |  |  | 19 |  | 20 |  | 8 |  | 12
WPL | 15 |  |  | 15 |  |  | 15 |  |  | 6 |  |  | 1 |  |  | 19 |  | 71 |  | 18 |  | 53
Finance Leases | LEASES Operating Leases - Alliant Energy’s, IPL’s and WPL’s operating leases primarily include leases of space on telecommunication towers and leases of property. Operating lease details are as follows (dollars in millions):
| December 31, 2021 |  | December 31, 2020
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Property, plant and equipment, net | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Other current liabilities | $2 |  | $1 |  | $1 |  | $2 |  | $1 |  | $1
Other liabilities | 12 |  | 8 |  | 4 |  | 13 |  | 8 |  | 5
Total operating lease liabilities | $14 |  | $9 |  | $5 |  | $15 |  | $9 |  | $6
Weighted average remaining lease term | 9 years |  | 11 years |  | 8 years |  | 10 years |  | 11 years |  | 9 years
Weighted average discount rate | 4% |  | 4% |  | 4% |  | 4% |  | 4% |  | 4%
Finance Leases - WPL is currently leasing the Sheboygan Falls Energy Facility from AEF’s Non-utility Generation business through 2025, the initial lease term. WPL is responsible for the operation of the EGU and has exclusive rights to its output. This finance lease contains two lease renewal periods, which are not included in the finance lease obligation, as well as an option to purchase the facility at the end of the initial lease term. For Alliant Energy, the leased Sheboygan Falls Energy Facility is eliminated upon consolidation and is therefore is not reflected in Alliant Energy’s amounts below. Related to its investments in solar generation, WPL entered into land lease agreements with unaffiliated parties that commenced in 2021. The leases have various terms with optional renewal periods that are assumed to be extended through the end of the estimated useful lives of the solar generating facilities. The leases do not contain purchase options and are fixed lease payments. Finance lease details are as follows (dollars in millions):
| Alliant Energy |  | WPL
| December 31, 2021 |  | December 31, 2021 |  | December 31, 2020 |  |
Property, plant and equipment, net: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $21 |  | $27 |  |
Leased land for solar generation | $11 |  | 11 |  | — |  |
| $11 |  | $32 |  | $27 |  |
Other current liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | $10 |  | $9 |  |
Leased land for solar generation | $1 |  | 1 |  | — |  |
| 1 |  | 11 |  | 9 |  |
Other liabilities: |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | n/a |  | 31 |  | 42 |  |
Leased land for solar generation | 11 |  | 11 |  | — |  |
| 11 |  | 42 |  | 42 |  |
Total finance lease liabilities | $12 |  | $53 |  | $51 |  |
Weighted average remaining lease term | 34 years |  | 10 years |  | 4 years |  |
Weighted average discount rate | 3% |  | 9% |  | 11% |  |
| 2021 |  | 2021 |  | 2020 |  | 2019
Depreciation and amortization expenses | $— |  | $6 |  | $6 |  | $6
Interest expense | — |  | 5 |  | 6 |  | 7
Total finance lease expense | $— |  | $11 |  | $12 |  | $13
Expected Maturities - As of December 31, 2021, expected maturities of lease liabilities were as follows (in millions):
| 2022 |  | 2023 |  | 2024 |  | 2025 |  | 2026 |  | Thereafter |  | Total |  | Less: amount representing interest |  | Present value of minimum lease payments
Operating Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $2 |  |  | $7 |  | $17 |  | $3 |  | $14
IPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 6 |  | 11 |  | 2 |  | 9
WPL | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  | 6 |  | 1 |  | 5
Finance Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy | — |  |  | — |  |  | — |  |  | — |  |  | 1 |  |  | 19 |  | 20 |  | 8 |  | 12
WPL | 15 |  |  | 15 |  |  | 15 |  |  | 6 |  |  | 1 |  |  | 19 |  | 71 |  | 18 |  | 53

X
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