EL DORADO ? Construction of a wind farm that would become the state’s biggest producer of wind energy could begin this spring.

The proposal for the $190 million Elk River Windfarm cleared a major hurdle this week with the fulfillment of Butler County commissioners’ requirement to find an energy company to purchase the farm’s power before construction begins.

Portland, Ore.-based PPM Energy bought the project from Greenlight Energy Inc. on Monday. The following day, Joplin, Mo.-based Empire District Electric Co. signed a 20-year contract to purchase the energy.

The proposal would bring 100 wind turbines — each nearly 400 feet tall — to an 8,000-acre stretch of private land three miles south of Beaumont.

The wind farm east of Wichita is expected to produce 150 megawatts of power — enough to power 42,000 homes a year.

Butler County Administrator Will Johnson said several steps remain before construction can begin, including county approval of a development plan, a decommissioning plan and building permits.

But the turbines still could be operational by late next year.

The wind farm issue has divided the county for two years.

Supporters say the turbines and any money they bring could help a cattle-ranching area that is struggling to survive. Others oppose bringing such structures near the Flint Hills, one of North America’s few remaining stands of native tallgrass prairie.

The argument tied up the proposal in court for the last 18 months, but Butler County attorney Norman Manley said all legal issues have now been settled.

Kansas is home to just one operating large-scale wind farm, the Gray County Wind Farm, which is outside Montezuma.