It would invest $2.5 billion in eight Colorado counties to fund the renewables expansion, which also includes 700MW of solar PV and 275MW in large-scale battery storage.
Xcel Energy would retire two coal-fired plants, Comanche 1 and Comanche 2, which have a combined capacity of 660MW.
The utility would also add more than 380MW of existing natural gas generation to provide baseload power to support the new renewable production facilities.
If approved by the Colorado Public Utilities Commission (CPUC), Xcel’s report would prompt a nearly-60% reduction in carbon emissions by 2026, and the utility would source nearly 55% of its energy from renewables.
Alice Jackson, president of Xcel Energy Colorado, said: "Our recommended plan secures long-term and low-cost renewable power, stimulates economic development in rural Colorado, and substantially reduces greenhouse gas emissions — all at a saving to customers."
In its proposal, Xcel added it planned to own 27% of the new renewable assets — or 500MW of the wind power installations.
New wind farms would be located in the north and east of Colorado, while about 500MW of the planned solar additions and 225MW of battery storage plants would be in the south of the state, with the balance in the north and west.
It would boost wind power capacity in Baca county by 162MW through repowering, Xcel stated, while adding 800MW in Cheyenne county and 169MW in Weld.
Xcel confirmed that the planned 1.1GW wind power expansion does not include its 600MW Rush Creek project, which is currently being built in the east of the state.
The CPUC is expected to rule on the plan by September 2018, the utility added.