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v3.19.3.a.u2

Commitments and Contingencies - Environmental Matters (Details) T in Millions, $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2019 Years | Apr. 30, 2019 degreecelsius | Dec. 31, 2018 USD ($) change | Dec. 31, 2019 USD ($) generating_units T MW | Dec. 31, 2018 USD ($) T
Mercury and Air Toxics | Electric |  |  |  |  |
Air Quality |  |  |  |  |
Revisions to mercury and air toxics standards | change |  |  | 0 |  |
Climate Change | Electric |  |  |  |  |
Air Quality |  |  |  |  |
Number of states challenging the ACE rule | Years | 22 |  |  |  |
Company goal for percentage of carbon dioxide emissions reductions by 2030 |  |  |  | 40.00% |
Capacity of coal generation retired since the beginning of 2018 | MW |  |  |  | 1,800 |
Per mile rate of methane emission reduction |  |  |  | 30.00% |
Carbon dioxide emissions | T |  |  |  | 21.8 | 26.4
Climate Change | Electric | Maximum |  |  |  |  |
Air Quality |  |  |  |  |
Global temperature increases limit | degreecelsius |  | 2 |  |  |
Climate Change | Natural gas |  |  |  |  |
Air Quality |  |  |  |  |
Carbon dioxide emissions | T |  |  |  | 29.4 | 29.4
Steam Electric Effluent Guidelines | Electric |  |  |  |  |
Water Quality |  |  |  |  |
Total units of OCPP and ERGS | generating_units |  |  |  | 6 |
Expected cost to achieve required discharge limits |  |  |  | $ 60.0 |
Manufactured Gas Plant Remediation | Natural gas |  |  |  |  |
Manufactured Gas Plant Remediation |  |  |  |  |
Regulatory assets recorded for remediation of manufactured gas plant sites |  |  | $ 687.1 | 685.5 | $ 687.1
Reserves for future environmental remediation of manufactured gas plant sites |  |  | $ 616.4 | $ 589.2 | $ 616.4
Renewables, Efficiency, and Conservation | Electric | Wisconsin |  |  |  |  |
Renewables, Efficiency, and Conservation |  |  |  |  |
Annual state renewable portfolio requirement, as a percent |  |  |  | 10.00% |
Percent of annual operating revenues used to fund renewable program |  |  |  | 1.20% |
Renewables, Efficiency, and Conservation | Electric | Wisconsin | WE |  |  |  |  |
Renewables, Efficiency, and Conservation |  |  |  |  |
Required renewable energy percent achieved |  |  |  | 8.27% |
Renewables, Efficiency, and Conservation | Electric | Wisconsin | WPS |  |  |  |  |
Renewables, Efficiency, and Conservation |  |  |  |  |
Required renewable energy percent achieved |  |  |  | 9.74% |
Renewables, Efficiency, and Conservation | Electric | Michigan |  |  |  |  |
Renewables, Efficiency, and Conservation |  |  |  |  |
State renewable portfolio requirement for years 2019 through 2020, as a percent |  |  |  | 12.50% |
Energy optimization target, as a percent |  |  |  | 1.00% |
State renewable portfolio requirement for 2021, as a percent |  |  |  | 15.00% |

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