Aerodynamics

The branch of dynamics that deals with the motion of air (and other gaseous fluids) and the forces acting on solids in motion relative to such fluids.

Aerofoil

A device, much like an airplane wing, that creates lift and minimizes drag. The blades have an aerofoil shape, which creates lift when moving air passes over the surface.

Electric service platform (ESP)

The central offshore platform that is the common electrical interconnection point for all of the turbines in the array. The ESP provides electrical protection and voltage step-up transformers.

Feathering

A method of overspeed protection. Feathering changes the angle or pitch of the blades to slow them in high-velocity winds.

Frequency

The number of complete alternations per second of an alternating current.

Generator

A device that converts mechanical energy into electric power.

Kilovolt (kV)

1000 volts.

Kinetic energy

Energy associated with movement; for example, the wind or a rock rolling down a hill.

Kilowatt hours (kWh)

A unit of work or energy equal one kilowatt in one hour (example, ten 100-watt light bulbs left on for one hour consumes one kWh of electricity).

Megawatt (MW)

1000 kilowatts or 1,000,000 Watts.

Nacelle

The portion of the turbine that encompasses the drive train, the bedplate on which it rests and the cover that protects the components from the elements. The nacelle for offshore turbines is specially designed to seal the interior from salt spray and moisture. The nacelle also includes maintenance cranes, access hatches and wind sensors.

Number of homes served

The average house in the US consumes 537 kWh/month or 6450 kWh/year.

Rotor

A complete system of blades that supplies all the force driving a wind generator. The rotor has three blades manufactured from fiberglass reinforced epoxy, mounted on a hub. The blades are pitch-regulated to continually control their angle to the wind and are designed to optimize energy production and to generate minimal noise.

Torque

A force that produces or tends to produce rotation.