HISTORY OF WIND ENERGY USE
Wind energy has been used for centuries to move ships, pump water, and grind grain. Simple windmills with sails for rotors were used as early as the 1st century AD for milling corn and irrigating crops in Persia. In the 12th century, windmills appeared in France and England and quickly spread throughout Europe, most famously in Holland. Windmills existed throughout Asia at the same time. Early windmill structures were made of wood and were often rotated by hand or oxen to augment the energy from the wind.
 Using wind to generate electricity is a more recent idea. Windmills, or wind turbines as the modern day versions are now called, were first adapted for creating electricity in the late 19th century. One of the first wind turbines was designed by Charles F. Brush, of Cleveland, Ohio, in 1888. The Brush machine used a picket-fence rotor 17 meters (56 feet) in diameter and featured a hinged tail to align the rotor into the wind. While not the first windmill to produce electricity, it was the first windmill to incorporate a step-up gearbox to more efficiently harvest the wind.
A step-up gearbox works to increase the rotational speed of a wind turbine’s blades and rotor system in the generator to produce electricity using the same mechanical principle as the gears on your bicycle. For example, when you shift to a higher gear on your bike, if you continue pedaling at the same speed, your tires’ rotation speed will increase and you will go faster! Conversely, if you shift to a lower gear (when going up a hill, for example), you need to pedal faster to maintain your same speed. Likewise, a step-up gearbox on a wind turbine increases the rotational speed of the blades from roughly 18 revolutions per minute (RPM’s) up to 1,800 RPM’s for the shaft going into the generator.
The technological advances of fossil fuel driven power technologies and industry during the industrial revolution of the 19th and 20th centuries caused wind power to fall out of favor in the early 20th century. However, the sharp oil price spikes of the 1970’s, along with the growing realization of the great environmental costs of burning fossil fuels, has rekindled interest in wind energy technology and its applications. For example, from 1980 until today, the size and efficiency of the typical turbine has jumped from 25 kilowatts (kW’s) up to 600 to 3,000 kilowatts.
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