Alliant Energy now expects to begin construction on its 150-megawatt (MW) Bent Tree North Wind Farm in Freeborn County, Minnesota, in the second quarter of 2028, with the facility reaching commercial operation in the second quarter of 2029 — a timeline the utility confirmed exclusively to us.

The schedule, shared by Alliant Energy’s communications team, runs roughly a year later than the plan the company set out when it unveiled the project in 2025, which targeted a 2027 construction start and an operational date by the end of 2028. Alliant Energy told us that Bent Tree North “is currently on track,” and that the refurbishment of its existing Bent Tree Wind Farm will be completed by the fourth quarter of 2027 — clearing the way for work on the expansion to begin.

The updated timeline follows the project’s final regulatory milestone. In April 2026, Alliant Energy secured unanimous approvals from the Minnesota Public Utilities Commission and the Public Service Commission of Wisconsin. Because the wind farm sits in Minnesota but will deliver power to Wisconsin customers, it required sign-off in both states.

Minnesota is gearing for more clean energy to power data centers such as Googles planned  Data Center in Hermantown.

A 150 MW addition

As currently designed, Bent Tree North will add approximately 150 MW of generating capacity — the project was originally announced at 153 MW — with around 32 turbines, enough to power at least 50,000 homes annually. The expansion is projected to deliver more than $100 million in tax revenue over its life, along with landowner lease payments and an estimated 100 to 150 jobs during construction. Alliant Energy notes that advances in turbine technology have improved net capacity factors, making newer wind farms more efficient than earlier installations.

Building on an established site

The project spans roughly 60 square miles, about 15 miles north of Albert Lea near Hartland, along State Highway 13. It expands the original Bent Tree Wind Farm, which has been operational since February 2011 and was presented to the Freeborn County Board of Commissioners during a 2025 workshop by Richard Miller, senior strategic project manager at Alliant Energy, and Greg Kaelberer, site manager of the Bent Tree Wind Farm.

The existing Bent Tree Wind Farm

The existing facility runs 122 Vestas V82 1.65 MW turbines for a total capacity of 201 MW, powering approximately 53,000 homes — ranking it among Minnesota’s largest wind farms alongside Buffalo Ridge (225 MW), Fenton (205.5 MW), Nobles (201 MW) and Odell (200 MW). To date, it has generated more than $5 million in tax revenue for Freeborn County and over $1.4 million for Hartland and Manchester Townships, with area landowners receiving more than $10 million in lease payments.

Project Factsheet: Bent Tree North Wind Farm

• Project name: Bent Tree North Wind Farm
• Developer / owner: Alliant Energy
• Location: Freeborn County, Minnesota — approx. 15 miles north of Albert Lea, near Hartland, along State Highway 13
• Capacity: Approximately 150 MW (originally announced at 153 MW)
• Turbines: Approximately 32
• Homes powered: At least 50,000 annually
• Project area: Roughly 60 square miles
• Approvals: Unanimously approved by the Minnesota PUC and Wisconsin PSC, April 2026
• Construction start: Q2 2028
• Operational date: Q2 2029
• Construction jobs: Estimated 100–150
• Projected tax revenue: Over $100 million over the project’s life
• Existing site refurbishment: Bent Tree Wind Farm refurbishment to be completed by Q4 2027
• Existing Bent Tree Wind Farm: 201 MW · 122 Vestas V82 1.65 MW turbines · operational since February 2011 · powers approx. 53,000 homes