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Property, Plant and Equipment | 12 Months Ended
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Dec. 31, 2014
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT At December 31, details of property, plant and equipment on the balance sheets were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2014 |  | 2013 |  | 2014 |  | 2013 |  | 2014 |  | 2013
Utility: |  |  |  |  |  |  |  |  |  |  |
Electric plant: |  |  |  |  |  |  |  |  |  |  |
In service: |  |  |  |  |  |  |  |  |  |  |
Generation (a) |  | $5,463.0 |  |  |  | $4,792.0 |  |  |  | $2,872.4 |  |  |  | $2,513.2 |  |  |  | $2,590.6 |  |  |  | $2,278.8 |
Distribution | 4,435.4 |  |  | 4,179.6 |  |  | 2,471.7 |  |  | 2,311.2 |  |  | 1,963.7 |  |  | 1,868.4 |
Other | 309.1 |  |  | 286.3 |  |  | 215.5 |  |  | 210.5 |  |  | 93.6 |  |  | 75.8 |
Anticipated to be retired early (b) | 157.6 |  |  | 157.8 |  |  | — |  |  | — |  |  | 157.6 |  |  | 157.8 |
Total electric plant | 10,365.1 |  |  | 9,415.7 |  |  | 5,559.6 |  |  | 5,034.9 |  |  | 4,805.5 |  |  | 4,380.8 |
Gas plant in service | 946.2 |  |  | 909.9 |  |  | 474.0 |  |  | 456.8 |  |  | 472.2 |  |  | 453.1 |
Other plant in service | 539.3 |  |  | 547.9 |  |  | 298.8 |  |  | 302.8 |  |  | 240.5 |  |  | 245.1 |
Accumulated depreciation | (3,923.1 | ) |  | (3,726.2 | ) |  | (2,124.5 | ) |  | (2,025.3 | ) |  | (1,798.6 | ) |  | (1,700.9 | )
Net plant | 7,927.5 |  |  | 7,147.3 |  |  | 4,207.9 |  |  | 3,769.2 |  |  | 3,719.6 |  |  | 3,378.1 |
Leased Sheboygan Falls Energy Facility, net (c) | — |  |  | — |  |  | — |  |  | — |  |  | 64.7 |  |  | 70.9 |
Construction work in progress | 479.1 |  |  | 677.9 |  |  | 325.0 |  |  | 346.4 |  |  | 154.1 |  |  | 331.5 |
Other, net | 22.3 |  |  | 22.3 |  |  | 21.8 |  |  | 21.2 |  |  | 0.5 |  |  | 1.1 |
Total utility | 8,428.9 |  |  | 7,847.5 |  |  | 4,554.7 |  |  | 4,136.8 |  |  | 3,938.9 |  |  | 3,781.6 |
Non-regulated and other: |  |  |  |  |  |  |  |  |  |  |
Non-regulated Generation, net (d) | 240.1 |  |  | 249.4 |  |  | — |  |  | — |  |  | — |  |  | — |
Corporate Services and other, net (e) | 269.4 |  |  | 229.6 |  |  | — |  |  | — |  |  | — |  |  | — |
Total non-regulated and other | 509.5 |  |  | 479.0 |  |  | — |  |  | — |  |  | — |  |  | — |
Total property, plant and equipment |  | $8,938.4 |  |  |  | $8,326.5 |  |  |  | $4,554.7 |  |  |  | $4,136.8 |  |  |  | $3,938.9 |  |  |  | $3,781.6 |
(a) | Includes various emission controls projects placed in service in 2014, which are discussed in “Emission Controls Projects” below.
(b) | In 2013, WPL received approval from MISO to retire Edgewater Unit 3, and Nelson Dewey Units 1 and 2. WPL currently anticipates retiring these EGUs by December 31, 2015, contingent on completion of transmission network upgrades needed for system reliability. WPL is recovering the remaining net book value of these EGUs over a 10-year period beginning January 1, 2013 pursuant to a May 2012 PSCW order.
(c) | Less accumulated amortization of $59.1 million and $52.9 million for WPL as of December 31, 2014 and 2013, respectively.
(d) | Less accumulated depreciation of $49.5 million and $40.0 million for Alliant Energy as of December 31, 2014 and 2013, respectively.
(e) | Less accumulated depreciation of $229.1 million and $214.2 million for Alliant Energy as of December 31, 2014 and 2013, respectively.
Utility - Emission Controls Projects - Various environmental controls projects to install scrubbers and baghouses at certain EGUs have been completed or are currently in progress. The scrubbers and baghouses reduce SO2 and mercury emissions at the EGUs and are expected to help meet requirements under the MATS Rule and CSAPR. IPL’s George Neal Unit 3 - Construction of a scrubber and baghouse at George Neal Unit 3 began in 2011 and was completed in 2014, which resulted in a transfer of the capitalized project costs from “Construction work in progress” to “Electric plant - Generation” in the above table for Alliant Energy and IPL in 2014. IPL owns a 28% interest in George Neal Unit 3. As of December 31, 2014, the capitalized project costs consisted of capital expenditures of $60 million and AFUDC of $4 million for IPL’s allocated portion of the George Neal Unit 3 scrubber and baghouse. IPL’s Ottumwa Unit 1 - Construction of a scrubber and baghouse at Ottumwa Unit 1 began in 2012 and was completed in 2014, which resulted in a transfer of the capitalized projects costs from “Construction work in progress” to “Electric plant - Generation” in the above table for Alliant Energy and IPL in 2014. IPL owns a 48% interest in Ottumwa Unit 1. As of December 31, 2014, the capitalized project costs consisted of capitalized expenditures of $154 million and AFUDC of $21 million for IPL’s allocated portion of the Ottumwa Unit 1 scrubber and baghouse. WPL’s Columbia Units 1 and 2 - Construction of scrubbers and baghouses at Columbia Units 1 and 2 began in 2012 and was completed in 2014, which resulted in a transfer of the capitalized project costs from “Construction work in progress” to “Electric plant - Generation” in the above table for Alliant Energy and WPL in 2014. WPL owns 46.2% interest in Columbia Units 1 and 2. As of December 31, 2014, the capitalized project costs consisted of capital expenditures of $272 million and AFUDC of $15 million for WPL’s allocated portion of the Columbia Units 1 and 2 scrubbers and baghouses. WPL’s Edgewater Unit 5 - WPL is currently installing a scrubber and baghouse at Edgewater Unit 5. Construction began in 2014 and is expected to be completed in 2016. As of December 31, 2014, Alliant Energy and WPL recorded capitalized expenditures of $90 million and AFUDC of $3 million for the scrubber and baghouse in “Construction work in progress” in the above table for Alliant Energy and WPL. Natural Gas-Fired Generation Project - IPL’s Marshalltown Generating Station - IPL is currently constructing Marshalltown, an approximate 650 MW natural gas-fired combined-cycle EGU. Construction began in 2014 and is expected to be completed in 2017. As of December 31, 2014, Alliant Energy and IPL recorded capitalized expenditures of $188 million and AFUDC of $4 million for Marshalltown in “Construction work in progress” in the above table for Alliant Energy and IPL. Anticipated Sales of IPL’s Minnesota Electric and Natural Gas Distribution Assets - In September 2013, IPL signed a definitive agreement to sell its Minnesota electric distribution assets to Southern Minnesota Energy Cooperative, a combined group of various neighboring electric cooperatives. Also in September 2013, IPL signed a definitive agreement to sell its Minnesota natural gas distribution assets to Minnesota Energy Resources Corporation, a subsidiary of Integrys Energy Group, Inc. Proceeds from the sales of the electric and natural gas distribution assets, which approximate the carrying value of such assets, are expected to be approximately $130 million and $10 million, respectively, subject to customary closing adjustments. The proceeds are expected to reduce Alliant Energy’s and IPL’s future financing requirements. In December 2014, the MPUC issued an order approving the proposed sale of IPL’s Minnesota natural gas distribution assets. Pending receipt of remaining regulatory approvals and various other contingencies, the natural gas and electric transactions are currently expected to be concluded in 2015. The sales price of the assets expected to be sold, which primarily consist of property, plant and equipment, and working capital items, is not expected to result in a material gain or loss. As of December 31, 2014, IPL’s assets and liabilities included in the electric sale agreement did not meet the criteria to be classified as held for sale due to uncertainties in the regulatory approval process that existed on such date. Refer to Notes 1(p) and 19 for further discussion of the natural gas distribution assets, which qualified as held for sale as of December 31, 2014. The electric distribution asset sales agreement includes a wholesale power supply agreement between IPL and Southern Minnesota Energy Cooperative, which is subject to FERC approval. The agreement contains a five-year termination notice, which may not be given until the fifth anniversary of the effective date of the agreement, resulting in a minimum term of 10 years. The agreement remains in effect indefinitely, unless notice to terminate is provided by either party. This wholesale power supply agreement includes standardized pricing mechanisms that are detailed in IPL’s current tariffs accepted by FERC through wholesale rate case proceedings. IPL’s current return on common equity authorized by FERC related to its wholesale electric rates is 10.97%. As a result of IPL’s requirement to supply electricity to Southern Minnesota Energy Cooperative under the wholesale power supply agreement, the sale of the electric distribution assets is not expected to have a significant impact on IPL’s current generation plans or operating results. AFUDC - AFUDC represents costs to finance construction additions including a return on equity component and cost of debt component as required by regulatory accounting. The concurrent credit for the amount of AFUDC capitalized is recorded as “Allowance for funds used during construction” in the income statements. The amount of AFUDC generated by equity and debt components was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2014 |  | 2013 |  | 2012 |  | 2014 |  | 2013 |  | 2012 |  | 2014 |  | 2013 |  | 2012
Equity |  | $23.1 |  |  |  | $20.3 |  |  |  | $14.1 |  |  |  | $17.1 |  |  |  | $13.8 |  |  |  | $5.2 |  |  |  | $6.0 |  |  |  | $6.5 |  |  |  | $8.9 |
Debt | 11.7 |  |  | 10.5 |  |  | 7.8 |  |  | 8.8 |  |  | 7.2 |  |  | 3.2 |  |  | 2.9 |  |  | 3.3 |  |  | 4.6 |
|  | $34.8 |  |  |  | $30.8 |  |  |  | $21.9 |  |  |  | $25.9 |  |  |  | $21.0 |  |  |  | $8.4 |  |  |  | $8.9 |  |  |  | $9.8 |  |  |  | $13.5 |
AFUDC related to various construction projects was recognized in the income statements as follows (in millions):
| 2014 |  | 2013 |  | 2012
IPL: |  |  |  |  |
Emission controls - Ottumwa Unit 1 |  | $10.6 |  |  |  | $8.0 |  |  |  | $2.0 |
Emission controls - George Neal Units 3 and 4 | 1.4 |  |  | 5.1 |  |  | 0.9 |
Marshalltown | 3.7 |  |  | — |  |  | — |
Other | 10.2 |  |  | 7.9 |  |  | 5.5 |
| 25.9 |  |  | 21.0 |  |  | 8.4 |
WPL: |  |  |  |  |
Emission controls - Columbia Units 1 and 2 | 4.0 |  |  | 7.2 |  |  | 3.9 |
Emission controls - Edgewater Unit 5 | 2.7 |  |  | — |  |  | 7.2 |
Other | 2.2 |  |  | 2.6 |  |  | 2.4 |
| 8.9 |  |  | 9.8 |  |  | 13.5 |
Alliant Energy |  | $34.8 |  |  |  | $30.8 |  |  |  | $21.9 |
In addition to the emission controls projects discussed above that were placed in service in 2014, a scrubber and baghouse was placed in service at IPL’s George Neal Unit 4 in 2013 and an SCR was placed in service at WPL’s Edgewater Unit 5 in 2012. Wind Generation Projects - IPL’s Whispering Willow - East Wind Project - In 2011, IPL received an order from the MPUC approving a temporary recovery rate for the Minnesota retail portion of its Whispering Willow - East wind project construction costs. In its order, the MPUC did not reach a conclusion as to the prudence of these project costs. The prudence of these project costs and the final recovery rate was addressed in a separate proceeding in 2013. The initial recovery rate approved by the MPUC was below the amount required by IPL to recover the Minnesota retail portion of its total project costs. Based on its interpretation of the order, IPL believed that it was probable it would not be allowed to recover the entire Minnesota retail portion of its project costs. IPL estimated the most likely outcome of the final rate proceeding would result in the MPUC effectively disallowing recovery of approximately $8 million of project costs out of a total of approximately $30 million of project costs allocated to the Minnesota retail jurisdiction. As a result, Alliant Energy and IPL recognized an $8 million impairment related to this probable disallowance in 2011. In December 2013, IPL received an order from the MPUC approving full cost recovery of the Minnesota retail portion of IPL’s Whispering Willow - East wind project construction costs effective January 1, 2013. As a result, Alliant Energy and IPL recognized a $7 million regulatory-related credit, which was recorded as an increase to property, plant and equipment on their balance sheets and a decrease to “Utility - Other operation and maintenance” in their income statements in 2013. Non-regulated and Other - The non-regulated and other property, plant and equipment recorded on Alliant Energy’s balance sheets includes the following: Non-regulated Generation - Franklin County Wind Project - The Franklin County wind project was placed into service in 2012 and is depreciated using the straight-line method over a 30-year period. As of December 31, 2014, Alliant Energy recorded $137 million on its balance sheet related to the wind project. Refer to Note 5(d) for discussion of a cash grant received in 2013 related to the wind project. Sheboygan Falls - Sheboygan Falls was placed into service in 2005 and is depreciated using the straight-line method over a 35-year period. As of December 31, 2014, Alliant Energy recorded $103 million on its balance sheet related to Sheboygan Falls. Corporate Services and Other - Property, plant and equipment related to Corporate Services includes computer software and the corporate headquarters building located in Madison, Wisconsin. Corporate Services is also implementing a new customer billing and information system for IPL and WPL, which is currently expected to be deployed in 2015. As of December 31, 2014, Alliant Energy recorded capitalized expenditures of $62 million and capitalized interest of $1 million for the customer billing and information system in “Corporate Services and other, net” in the above table for Alliant Energy. Property, plant and equipment related to Transportation includes a short-line railway in Iowa, a barge terminal on the Mississippi River and a coal terminal in Williams, Iowa. The Corporate Services and Other property, plant and equipment is depreciated using the straight-line method over periods ranging from 5 to 30 years.
IPL [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT At December 31, details of property, plant and equipment on the balance sheets were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2014 |  | 2013 |  | 2014 |  | 2013 |  | 2014 |  | 2013
Utility: |  |  |  |  |  |  |  |  |  |  |
Electric plant: |  |  |  |  |  |  |  |  |  |  |
In service: |  |  |  |  |  |  |  |  |  |  |
Generation (a) |  | $5,463.0 |  |  |  | $4,792.0 |  |  |  | $2,872.4 |  |  |  | $2,513.2 |  |  |  | $2,590.6 |  |  |  | $2,278.8 |
Distribution | 4,435.4 |  |  | 4,179.6 |  |  | 2,471.7 |  |  | 2,311.2 |  |  | 1,963.7 |  |  | 1,868.4 |
Other | 309.1 |  |  | 286.3 |  |  | 215.5 |  |  | 210.5 |  |  | 93.6 |  |  | 75.8 |
Anticipated to be retired early (b) | 157.6 |  |  | 157.8 |  |  | — |  |  | — |  |  | 157.6 |  |  | 157.8 |
Total electric plant | 10,365.1 |  |  | 9,415.7 |  |  | 5,559.6 |  |  | 5,034.9 |  |  | 4,805.5 |  |  | 4,380.8 |
Gas plant in service | 946.2 |  |  | 909.9 |  |  | 474.0 |  |  | 456.8 |  |  | 472.2 |  |  | 453.1 |
Other plant in service | 539.3 |  |  | 547.9 |  |  | 298.8 |  |  | 302.8 |  |  | 240.5 |  |  | 245.1 |
Accumulated depreciation | (3,923.1 | ) |  | (3,726.2 | ) |  | (2,124.5 | ) |  | (2,025.3 | ) |  | (1,798.6 | ) |  | (1,700.9 | )
Net plant | 7,927.5 |  |  | 7,147.3 |  |  | 4,207.9 |  |  | 3,769.2 |  |  | 3,719.6 |  |  | 3,378.1 |
Leased Sheboygan Falls Energy Facility, net (c) | — |  |  | — |  |  | — |  |  | — |  |  | 64.7 |  |  | 70.9 |
Construction work in progress | 479.1 |  |  | 677.9 |  |  | 325.0 |  |  | 346.4 |  |  | 154.1 |  |  | 331.5 |
Other, net | 22.3 |  |  | 22.3 |  |  | 21.8 |  |  | 21.2 |  |  | 0.5 |  |  | 1.1 |
Total utility | 8,428.9 |  |  | 7,847.5 |  |  | 4,554.7 |  |  | 4,136.8 |  |  | 3,938.9 |  |  | 3,781.6 |
Non-regulated and other: |  |  |  |  |  |  |  |  |  |  |
Non-regulated Generation, net (d) | 240.1 |  |  | 249.4 |  |  | — |  |  | — |  |  | — |  |  | — |
Corporate Services and other, net (e) | 269.4 |  |  | 229.6 |  |  | — |  |  | — |  |  | — |  |  | — |
Total non-regulated and other | 509.5 |  |  | 479.0 |  |  | — |  |  | — |  |  | — |  |  | — |
Total property, plant and equipment |  | $8,938.4 |  |  |  | $8,326.5 |  |  |  | $4,554.7 |  |  |  | $4,136.8 |  |  |  | $3,938.9 |  |  |  | $3,781.6 |
(a) | Includes various emission controls projects placed in service in 2014, which are discussed in “Emission Controls Projects” below.
(b) | In 2013, WPL received approval from MISO to retire Edgewater Unit 3, and Nelson Dewey Units 1 and 2. WPL currently anticipates retiring these EGUs by December 31, 2015, contingent on completion of transmission network upgrades needed for system reliability. WPL is recovering the remaining net book value of these EGUs over a 10-year period beginning January 1, 2013 pursuant to a May 2012 PSCW order.
(c) | Less accumulated amortization of $59.1 million and $52.9 million for WPL as of December 31, 2014 and 2013, respectively.
(d) | Less accumulated depreciation of $49.5 million and $40.0 million for Alliant Energy as of December 31, 2014 and 2013, respectively.
(e) | Less accumulated depreciation of $229.1 million and $214.2 million for Alliant Energy as of December 31, 2014 and 2013, respectively.
Utility - Emission Controls Projects - Various environmental controls projects to install scrubbers and baghouses at certain EGUs have been completed or are currently in progress. The scrubbers and baghouses reduce SO2 and mercury emissions at the EGUs and are expected to help meet requirements under the MATS Rule and CSAPR. IPL’s George Neal Unit 3 - Construction of a scrubber and baghouse at George Neal Unit 3 began in 2011 and was completed in 2014, which resulted in a transfer of the capitalized project costs from “Construction work in progress” to “Electric plant - Generation” in the above table for Alliant Energy and IPL in 2014. IPL owns a 28% interest in George Neal Unit 3. As of December 31, 2014, the capitalized project costs consisted of capital expenditures of $60 million and AFUDC of $4 million for IPL’s allocated portion of the George Neal Unit 3 scrubber and baghouse. IPL’s Ottumwa Unit 1 - Construction of a scrubber and baghouse at Ottumwa Unit 1 began in 2012 and was completed in 2014, which resulted in a transfer of the capitalized projects costs from “Construction work in progress” to “Electric plant - Generation” in the above table for Alliant Energy and IPL in 2014. IPL owns a 48% interest in Ottumwa Unit 1. As of December 31, 2014, the capitalized project costs consisted of capitalized expenditures of $154 million and AFUDC of $21 million for IPL’s allocated portion of the Ottumwa Unit 1 scrubber and baghouse. WPL’s Columbia Units 1 and 2 - Construction of scrubbers and baghouses at Columbia Units 1 and 2 began in 2012 and was completed in 2014, which resulted in a transfer of the capitalized project costs from “Construction work in progress” to “Electric plant - Generation” in the above table for Alliant Energy and WPL in 2014. WPL owns 46.2% interest in Columbia Units 1 and 2. As of December 31, 2014, the capitalized project costs consisted of capital expenditures of $272 million and AFUDC of $15 million for WPL’s allocated portion of the Columbia Units 1 and 2 scrubbers and baghouses. WPL’s Edgewater Unit 5 - WPL is currently installing a scrubber and baghouse at Edgewater Unit 5. Construction began in 2014 and is expected to be completed in 2016. As of December 31, 2014, Alliant Energy and WPL recorded capitalized expenditures of $90 million and AFUDC of $3 million for the scrubber and baghouse in “Construction work in progress” in the above table for Alliant Energy and WPL. Natural Gas-Fired Generation Project - IPL’s Marshalltown Generating Station - IPL is currently constructing Marshalltown, an approximate 650 MW natural gas-fired combined-cycle EGU. Construction began in 2014 and is expected to be completed in 2017. As of December 31, 2014, Alliant Energy and IPL recorded capitalized expenditures of $188 million and AFUDC of $4 million for Marshalltown in “Construction work in progress” in the above table for Alliant Energy and IPL. Anticipated Sales of IPL’s Minnesota Electric and Natural Gas Distribution Assets - In September 2013, IPL signed a definitive agreement to sell its Minnesota electric distribution assets to Southern Minnesota Energy Cooperative, a combined group of various neighboring electric cooperatives. Also in September 2013, IPL signed a definitive agreement to sell its Minnesota natural gas distribution assets to Minnesota Energy Resources Corporation, a subsidiary of Integrys Energy Group, Inc. Proceeds from the sales of the electric and natural gas distribution assets, which approximate the carrying value of such assets, are expected to be approximately $130 million and $10 million, respectively, subject to customary closing adjustments. The proceeds are expected to reduce Alliant Energy’s and IPL’s future financing requirements. In December 2014, the MPUC issued an order approving the proposed sale of IPL’s Minnesota natural gas distribution assets. Pending receipt of remaining regulatory approvals and various other contingencies, the natural gas and electric transactions are currently expected to be concluded in 2015. The sales price of the assets expected to be sold, which primarily consist of property, plant and equipment, and working capital items, is not expected to result in a material gain or loss. As of December 31, 2014, IPL’s assets and liabilities included in the electric sale agreement did not meet the criteria to be classified as held for sale due to uncertainties in the regulatory approval process that existed on such date. Refer to Notes 1(p) and 19 for further discussion of the natural gas distribution assets, which qualified as held for sale as of December 31, 2014. The electric distribution asset sales agreement includes a wholesale power supply agreement between IPL and Southern Minnesota Energy Cooperative, which is subject to FERC approval. The agreement contains a five-year termination notice, which may not be given until the fifth anniversary of the effective date of the agreement, resulting in a minimum term of 10 years. The agreement remains in effect indefinitely, unless notice to terminate is provided by either party. This wholesale power supply agreement includes standardized pricing mechanisms that are detailed in IPL’s current tariffs accepted by FERC through wholesale rate case proceedings. IPL’s current return on common equity authorized by FERC related to its wholesale electric rates is 10.97%. As a result of IPL’s requirement to supply electricity to Southern Minnesota Energy Cooperative under the wholesale power supply agreement, the sale of the electric distribution assets is not expected to have a significant impact on IPL’s current generation plans or operating results. AFUDC - AFUDC represents costs to finance construction additions including a return on equity component and cost of debt component as required by regulatory accounting. The concurrent credit for the amount of AFUDC capitalized is recorded as “Allowance for funds used during construction” in the income statements. The amount of AFUDC generated by equity and debt components was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2014 |  | 2013 |  | 2012 |  | 2014 |  | 2013 |  | 2012 |  | 2014 |  | 2013 |  | 2012
Equity |  | $23.1 |  |  |  | $20.3 |  |  |  | $14.1 |  |  |  | $17.1 |  |  |  | $13.8 |  |  |  | $5.2 |  |  |  | $6.0 |  |  |  | $6.5 |  |  |  | $8.9 |
Debt | 11.7 |  |  | 10.5 |  |  | 7.8 |  |  | 8.8 |  |  | 7.2 |  |  | 3.2 |  |  | 2.9 |  |  | 3.3 |  |  | 4.6 |
|  | $34.8 |  |  |  | $30.8 |  |  |  | $21.9 |  |  |  | $25.9 |  |  |  | $21.0 |  |  |  | $8.4 |  |  |  | $8.9 |  |  |  | $9.8 |  |  |  | $13.5 |
AFUDC related to various construction projects was recognized in the income statements as follows (in millions):
| 2014 |  | 2013 |  | 2012
IPL: |  |  |  |  |
Emission controls - Ottumwa Unit 1 |  | $10.6 |  |  |  | $8.0 |  |  |  | $2.0 |
Emission controls - George Neal Units 3 and 4 | 1.4 |  |  | 5.1 |  |  | 0.9 |
Marshalltown | 3.7 |  |  | — |  |  | — |
Other | 10.2 |  |  | 7.9 |  |  | 5.5 |
| 25.9 |  |  | 21.0 |  |  | 8.4 |
WPL: |  |  |  |  |
Emission controls - Columbia Units 1 and 2 | 4.0 |  |  | 7.2 |  |  | 3.9 |
Emission controls - Edgewater Unit 5 | 2.7 |  |  | — |  |  | 7.2 |
Other | 2.2 |  |  | 2.6 |  |  | 2.4 |
| 8.9 |  |  | 9.8 |  |  | 13.5 |
Alliant Energy |  | $34.8 |  |  |  | $30.8 |  |  |  | $21.9 |
In addition to the emission controls projects discussed above that were placed in service in 2014, a scrubber and baghouse was placed in service at IPL’s George Neal Unit 4 in 2013 and an SCR was placed in service at WPL’s Edgewater Unit 5 in 2012. Wind Generation Projects - IPL’s Whispering Willow - East Wind Project - In 2011, IPL received an order from the MPUC approving a temporary recovery rate for the Minnesota retail portion of its Whispering Willow - East wind project construction costs. In its order, the MPUC did not reach a conclusion as to the prudence of these project costs. The prudence of these project costs and the final recovery rate was addressed in a separate proceeding in 2013. The initial recovery rate approved by the MPUC was below the amount required by IPL to recover the Minnesota retail portion of its total project costs. Based on its interpretation of the order, IPL believed that it was probable it would not be allowed to recover the entire Minnesota retail portion of its project costs. IPL estimated the most likely outcome of the final rate proceeding would result in the MPUC effectively disallowing recovery of approximately $8 million of project costs out of a total of approximately $30 million of project costs allocated to the Minnesota retail jurisdiction. As a result, Alliant Energy and IPL recognized an $8 million impairment related to this probable disallowance in 2011. In December 2013, IPL received an order from the MPUC approving full cost recovery of the Minnesota retail portion of IPL’s Whispering Willow - East wind project construction costs effective January 1, 2013. As a result, Alliant Energy and IPL recognized a $7 million regulatory-related credit, which was recorded as an increase to property, plant and equipment on their balance sheets and a decrease to “Utility - Other operation and maintenance” in their income statements in 2013.
WPL [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT At December 31, details of property, plant and equipment on the balance sheets were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2014 |  | 2013 |  | 2014 |  | 2013 |  | 2014 |  | 2013
Utility: |  |  |  |  |  |  |  |  |  |  |
Electric plant: |  |  |  |  |  |  |  |  |  |  |
In service: |  |  |  |  |  |  |  |  |  |  |
Generation (a) |  | $5,463.0 |  |  |  | $4,792.0 |  |  |  | $2,872.4 |  |  |  | $2,513.2 |  |  |  | $2,590.6 |  |  |  | $2,278.8 |
Distribution | 4,435.4 |  |  | 4,179.6 |  |  | 2,471.7 |  |  | 2,311.2 |  |  | 1,963.7 |  |  | 1,868.4 |
Other | 309.1 |  |  | 286.3 |  |  | 215.5 |  |  | 210.5 |  |  | 93.6 |  |  | 75.8 |
Anticipated to be retired early (b) | 157.6 |  |  | 157.8 |  |  | — |  |  | — |  |  | 157.6 |  |  | 157.8 |
Total electric plant | 10,365.1 |  |  | 9,415.7 |  |  | 5,559.6 |  |  | 5,034.9 |  |  | 4,805.5 |  |  | 4,380.8 |
Gas plant in service | 946.2 |  |  | 909.9 |  |  | 474.0 |  |  | 456.8 |  |  | 472.2 |  |  | 453.1 |
Other plant in service | 539.3 |  |  | 547.9 |  |  | 298.8 |  |  | 302.8 |  |  | 240.5 |  |  | 245.1 |
Accumulated depreciation | (3,923.1 | ) |  | (3,726.2 | ) |  | (2,124.5 | ) |  | (2,025.3 | ) |  | (1,798.6 | ) |  | (1,700.9 | )
Net plant | 7,927.5 |  |  | 7,147.3 |  |  | 4,207.9 |  |  | 3,769.2 |  |  | 3,719.6 |  |  | 3,378.1 |
Leased Sheboygan Falls Energy Facility, net (c) | — |  |  | — |  |  | — |  |  | — |  |  | 64.7 |  |  | 70.9 |
Construction work in progress | 479.1 |  |  | 677.9 |  |  | 325.0 |  |  | 346.4 |  |  | 154.1 |  |  | 331.5 |
Other, net | 22.3 |  |  | 22.3 |  |  | 21.8 |  |  | 21.2 |  |  | 0.5 |  |  | 1.1 |
Total utility | 8,428.9 |  |  | 7,847.5 |  |  | 4,554.7 |  |  | 4,136.8 |  |  | 3,938.9 |  |  | 3,781.6 |
Non-regulated and other: |  |  |  |  |  |  |  |  |  |  |
Non-regulated Generation, net (d) | 240.1 |  |  | 249.4 |  |  | — |  |  | — |  |  | — |  |  | — |
Corporate Services and other, net (e) | 269.4 |  |  | 229.6 |  |  | — |  |  | — |  |  | — |  |  | — |
Total non-regulated and other | 509.5 |  |  | 479.0 |  |  | — |  |  | — |  |  | — |  |  | — |
Total property, plant and equipment |  | $8,938.4 |  |  |  | $8,326.5 |  |  |  | $4,554.7 |  |  |  | $4,136.8 |  |  |  | $3,938.9 |  |  |  | $3,781.6 |
(a) | Includes various emission controls projects placed in service in 2014, which are discussed in “Emission Controls Projects” below.
(b) | In 2013, WPL received approval from MISO to retire Edgewater Unit 3, and Nelson Dewey Units 1 and 2. WPL currently anticipates retiring these EGUs by December 31, 2015, contingent on completion of transmission network upgrades needed for system reliability. WPL is recovering the remaining net book value of these EGUs over a 10-year period beginning January 1, 2013 pursuant to a May 2012 PSCW order.
(c) | Less accumulated amortization of $59.1 million and $52.9 million for WPL as of December 31, 2014 and 2013, respectively.
(d) | Less accumulated depreciation of $49.5 million and $40.0 million for Alliant Energy as of December 31, 2014 and 2013, respectively.
(e) | Less accumulated depreciation of $229.1 million and $214.2 million for Alliant Energy as of December 31, 2014 and 2013, respectively.
Utility - Emission Controls Projects - Various environmental controls projects to install scrubbers and baghouses at certain EGUs have been completed or are currently in progress. The scrubbers and baghouses reduce SO2 and mercury emissions at the EGUs and are expected to help meet requirements under the MATS Rule and CSAPR. IPL’s George Neal Unit 3 - Construction of a scrubber and baghouse at George Neal Unit 3 began in 2011 and was completed in 2014, which resulted in a transfer of the capitalized project costs from “Construction work in progress” to “Electric plant - Generation” in the above table for Alliant Energy and IPL in 2014. IPL owns a 28% interest in George Neal Unit 3. As of December 31, 2014, the capitalized project costs consisted of capital expenditures of $60 million and AFUDC of $4 million for IPL’s allocated portion of the George Neal Unit 3 scrubber and baghouse. IPL’s Ottumwa Unit 1 - Construction of a scrubber and baghouse at Ottumwa Unit 1 began in 2012 and was completed in 2014, which resulted in a transfer of the capitalized projects costs from “Construction work in progress” to “Electric plant - Generation” in the above table for Alliant Energy and IPL in 2014. IPL owns a 48% interest in Ottumwa Unit 1. As of December 31, 2014, the capitalized project costs consisted of capitalized expenditures of $154 million and AFUDC of $21 million for IPL’s allocated portion of the Ottumwa Unit 1 scrubber and baghouse. WPL’s Columbia Units 1 and 2 - Construction of scrubbers and baghouses at Columbia Units 1 and 2 began in 2012 and was completed in 2014, which resulted in a transfer of the capitalized project costs from “Construction work in progress” to “Electric plant - Generation” in the above table for Alliant Energy and WPL in 2014. WPL owns 46.2% interest in Columbia Units 1 and 2. As of December 31, 2014, the capitalized project costs consisted of capital expenditures of $272 million and AFUDC of $15 million for WPL’s allocated portion of the Columbia Units 1 and 2 scrubbers and baghouses. WPL’s Edgewater Unit 5 - WPL is currently installing a scrubber and baghouse at Edgewater Unit 5. Construction began in 2014 and is expected to be completed in 2016. As of December 31, 2014, Alliant Energy and WPL recorded capitalized expenditures of $90 million and AFUDC of $3 million for the scrubber and baghouse in “Construction work in progress” in the above table for Alliant Energy and WPL. Natural Gas-Fired Generation Project - IPL’s Marshalltown Generating Station - IPL is currently constructing Marshalltown, an approximate 650 MW natural gas-fired combined-cycle EGU. Construction began in 2014 and is expected to be completed in 2017. As of December 31, 2014, Alliant Energy and IPL recorded capitalized expenditures of $188 million and AFUDC of $4 million for Marshalltown in “Construction work in progress” in the above table for Alliant Energy and IPL. Anticipated Sales of IPL’s Minnesota Electric and Natural Gas Distribution Assets - In September 2013, IPL signed a definitive agreement to sell its Minnesota electric distribution assets to Southern Minnesota Energy Cooperative, a combined group of various neighboring electric cooperatives. Also in September 2013, IPL signed a definitive agreement to sell its Minnesota natural gas distribution assets to Minnesota Energy Resources Corporation, a subsidiary of Integrys Energy Group, Inc. Proceeds from the sales of the electric and natural gas distribution assets, which approximate the carrying value of such assets, are expected to be approximately $130 million and $10 million, respectively, subject to customary closing adjustments. The proceeds are expected to reduce Alliant Energy’s and IPL’s future financing requirements. In December 2014, the MPUC issued an order approving the proposed sale of IPL’s Minnesota natural gas distribution assets. Pending receipt of remaining regulatory approvals and various other contingencies, the natural gas and electric transactions are currently expected to be concluded in 2015. The sales price of the assets expected to be sold, which primarily consist of property, plant and equipment, and working capital items, is not expected to result in a material gain or loss. As of December 31, 2014, IPL’s assets and liabilities included in the electric sale agreement did not meet the criteria to be classified as held for sale due to uncertainties in the regulatory approval process that existed on such date. Refer to Notes 1(p) and 19 for further discussion of the natural gas distribution assets, which qualified as held for sale as of December 31, 2014. The electric distribution asset sales agreement includes a wholesale power supply agreement between IPL and Southern Minnesota Energy Cooperative, which is subject to FERC approval. The agreement contains a five-year termination notice, which may not be given until the fifth anniversary of the effective date of the agreement, resulting in a minimum term of 10 years. The agreement remains in effect indefinitely, unless notice to terminate is provided by either party. This wholesale power supply agreement includes standardized pricing mechanisms that are detailed in IPL’s current tariffs accepted by FERC through wholesale rate case proceedings. IPL’s current return on common equity authorized by FERC related to its wholesale electric rates is 10.97%. As a result of IPL’s requirement to supply electricity to Southern Minnesota Energy Cooperative under the wholesale power supply agreement, the sale of the electric distribution assets is not expected to have a significant impact on IPL’s current generation plans or operating results. AFUDC - AFUDC represents costs to finance construction additions including a return on equity component and cost of debt component as required by regulatory accounting. The concurrent credit for the amount of AFUDC capitalized is recorded as “Allowance for funds used during construction” in the income statements. The amount of AFUDC generated by equity and debt components was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2014 |  | 2013 |  | 2012 |  | 2014 |  | 2013 |  | 2012 |  | 2014 |  | 2013 |  | 2012
Equity |  | $23.1 |  |  |  | $20.3 |  |  |  | $14.1 |  |  |  | $17.1 |  |  |  | $13.8 |  |  |  | $5.2 |  |  |  | $6.0 |  |  |  | $6.5 |  |  |  | $8.9 |
Debt | 11.7 |  |  | 10.5 |  |  | 7.8 |  |  | 8.8 |  |  | 7.2 |  |  | 3.2 |  |  | 2.9 |  |  | 3.3 |  |  | 4.6 |
|  | $34.8 |  |  |  | $30.8 |  |  |  | $21.9 |  |  |  | $25.9 |  |  |  | $21.0 |  |  |  | $8.4 |  |  |  | $8.9 |  |  |  | $9.8 |  |  |  | $13.5 |
AFUDC related to various construction projects was recognized in the income statements as follows (in millions):
| 2014 |  | 2013 |  | 2012
IPL: |  |  |  |  |
Emission controls - Ottumwa Unit 1 |  | $10.6 |  |  |  | $8.0 |  |  |  | $2.0 |
Emission controls - George Neal Units 3 and 4 | 1.4 |  |  | 5.1 |  |  | 0.9 |
Marshalltown | 3.7 |  |  | — |  |  | — |
Other | 10.2 |  |  | 7.9 |  |  | 5.5 |
| 25.9 |  |  | 21.0 |  |  | 8.4 |
WPL: |  |  |  |  |
Emission controls - Columbia Units 1 and 2 | 4.0 |  |  | 7.2 |  |  | 3.9 |
Emission controls - Edgewater Unit 5 | 2.7 |  |  | — |  |  | 7.2 |
Other | 2.2 |  |  | 2.6 |  |  | 2.4 |
| 8.9 |  |  | 9.8 |  |  | 13.5 |
Alliant Energy |  | $34.8 |  |  |  | $30.8 |  |  |  | $21.9 |
In addition to the emission controls projects discussed above that were placed in service in 2014, a scrubber and baghouse was placed in service at IPL’s George Neal Unit 4 in 2013 and an SCR was placed in service at WPL’s Edgewater Unit 5 in 2012.

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