Getting your Trinity Audio player ready...

Preparations are being made for a site-wide refurbishment project at the Bent Tree Wind Farm in Manchester and Hartland starting this summer and continuing through November 2027.

Richard Miller, senior strategic project manager with Alliant Energy, and Greg Kaelberer, site manager with the Bent Tree Wind Farm, presented about the project to the Freeborn County Board of Commissioners on Tuesday during the board’s workshop.

Bent Tree Wind Farm has been operational since February 2011, includes 122 turbines and is capable of producing up to 201 megawatts of energy, enough to power 53,000 homes.

They stated Alliant Energy’s clean energy vision calls for achieving a 50% reduction in carbon dioxide emissions from 2005 levels by 2023, eliminating all coal from their generation fleet by 2040 and meeting a goal of net-zero carbon dioxide emissions from the electricity they generate by 2050.

As the company continues toward that vision, it is the third largest owner-operator of regulated wind in the United States with nearly 1,800 megawatts of power in Minnesota, Iowa and Wisconsin.

Bent Tree Wind Farm, specifically, has thus far reduced carbon dioxide emissions by 3.5 million metric tons and is estimated to reduce emissions by an additional 11 million metric tons by 2040, according to the information shared.

To date, it has also generated over $5 million of tax revenue to Freeborn County and over $1.4 million to Hartland and Manchester townships, according to information presented to the board. Landowners have received over $10 million in lease payments and are estimated to receive $32 million more over the next 20 years.

An evaluation was conducted on the wind farm to determine whether to repower, or replace aging parts with new components, and the evaluation validated doing so. The Inflation Reduction Act also provided for Alliant to qualify the farm for a new 10-year period of production tax credits.

The project calls for replacing box pads for padmount transformers, the padmount transformers, gearboxes, main bearings, generator bearings and cooling system, blade bearings, yaw and pitch systems, blade protection application and blade fiberglass image, as well as a variety of other internal components.

The box pads and the padmount transformers will be replaced from August through November of 2025, with other parts replacement from May to November 2026 and from May through November 2027.

Miller said the company is working on a road use agreement with the county that is based on a similar refurbishment project.

During the project itself, they plan to have weekly meetings with the county to discuss and address any issues, such as dust control or others.

Miller said cranes that will be used will be broken down and transported on Department of Transportation-permitted flatbeds for each turbine, and no crossings will take place over county drainage tile to mitigate any potential damage.

Alliant Energy is reaching out to landowners about the project and timeframe, as well as erosion control and to provide coordination of crop dusting to mitigate crews being sprayed.

Interim County Administrator Darrell Pettis, who was not working for the county when the wind farm was initially approved, asked whether the farm was approved by the Public Utilities Commission or through a conditional use permit.

The men said it was approved by the Public Utilities Commission, and Kaelberer said as long as they are not changing the size of the turbine blades with this project, it is just considered major maintenance.

Commissioner Dawn Kaasa asked about a construction use agreement for tile crossings and County Engineer Phil Wacholz and Auditor-Treasurer Kelly Hendrickson said it will be signed off on by the county’s lawyer. The agreement will outline when the company will fix tile that is damaged because of the construction.