Each turbine is more than 262 feet high and includes three blades that are each 125 feet long and a nacelle — which contains the gearbox and generator — the size of a camper trailer.

Horizon Wind Energy operates more than 15 wind farms across the country, including the Twin Groves I and II wind farms in eastern McLean county. Those farms, which became operational in March 2007 and early 2008, respectively, have a combined 240 turbines and a generating capacity of 396 MW.

Horizon Wind Energy also is developing the Top Crop I wind farm, which is of similar size to Rail Splitter, in LaSalle County. That farm is the first phase of a larger project that will include wind farms in Grundy and Livingston counties.

Construction began on Rail Splitter Wind Farm, on Interstate 155 in Logan and Tazewell counties about 60 miles from Springfield, in July 2008, Whitlock said. Completing a trench for underground wiring was one of the final construction elements.

Horizon Wind Energy officials say the annual environmental benefits of Rail Splitter will be equivalent to taking 18,000 cars off the road.

Horizon Wind Energy sells the electricity generated by its farms on the wholesale market, typically to a utility, Whitlock said. There are no buyers as yet for Rail Splitter electricity.

“We’re in discussions involving a couple of different parties,” he said.

Horizon Wind Energy is owned by EDP Renovaveis SA, a subsidiary of Energias de Portugal SA headquartered in Lisbon, Portugal.