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Elements of the wind plant

Wind machines
The basic components of the wind machines include a tubular steel tower, turbine generator, housing for the turbine (called the nacelle), three fiberglass blades and electronic equipment that monitors and controls the machine.

The turbine generator and blade assemblies -- which weigh in excess of 30,000 pounds -- are placed on towers that are more than 130 feet high. Each machine produces power at 480 volts, which is stepped up to 13,800 volts at transformers at the tower base. The transformers are all linked to an underground wiring system that sends the power from the machines to the windplant substation.

Each wind machine is designed to rotate on its axis and adjust the angle or tilt of the blades to efficiently capture energy from the wind. Each machine has an on-board weather station and computer control system that provide real-time information on wind speed and direction. The information controls the machine so it always captures the maximum amount of energy from the wind. This ongoing monitoring and adjustment is known as "chasing the wind."

The machines begin production when the wind velocity is approximately 8 mph and are producing full power when the wind velocity is about 20 mph. Power production continues up to 65 mph, when the blade surfaces are turned perpendicular to the wind and the machines automatically shut down.

Substation
The windplant substation -- which will initially have one large transformer -- collects all the wind power and transforms the voltage again, bumping it to 235,000 volts for transmission through the regional grid. The substation also ensures that the windplant power is delivered to the transmission grid at standard and consistent voltage and frequency levels.

Transmission lines
Approximately 28 miles of transmission line connect the windplant to the regional transmission grid. The design and construction specifications for this line were part of the overall environmental impact statement and permitting process for the project. The lines that relay power from the wind machines to the substation are buried in order to prevent birds from perching on the wires.