A Brief History of Wind Power

China may have been the birthplace of the windmill. The earliest actual documentation of a Chinese windmill was in 1219 A.D. by the Chinese statesman Yehlu Chhu-Tshai. It is assumed to have been used primarily for grain grinding and water pumping.

A vertical axis system called panemone device was developed in Persia about 500-900 A.D. It was apparently used for water pumping. The first document design features vertical sails made of bundles of reeds or wood which were attached to the central vertical shaft by horizontal struts.

Grain grinding windmills consisted of a grinding stone affixed to a vertical shaft driven by a horizontally mounted wind rotor. The mill machinery was commonly enclosed in a building. Wooden cog-and-ring gears were utilized for the vertical axis rotor to drive the horizontal axis grindstone.

Rotor designs have their roots in sailboat design from which early knowledge of wind forces was learned by experimentation. On the island of Crete sail-rotor windmills are still used to pump water. Steel bladed versions of these pumps were used throughout the American heartland in the late 1800's. By 1970 over six million small windmills were installed in the U.S. primarily for pumping water. Raised water towers were a common storage method that provided on demand water pressure delivery. By the mid-1920's Parris-Dunn and Jacobs were major suppliers for wind-electric to the mid-west and Great Plains area. The early success of the Midwest wind turbines actually set the stage for the possibility of more extensive wind energy development in the future.

The Dutch as early as 1390 developed the windmill essentially as a milling factory with multi-story towers with separate floors for grinding, chaffing, and storing the milled grain. At the bottom were living quarters for the windsmith's family. The Dutch made many improvements to optimizing the power output and protect the rotors during storms.

In 1888 Charles F. Brush constructed a large electric generation windmill in Cleveland, Ohio. It was a postmill that featured a tail to swing the rotor into the wind direction. It utilized a step-up gear box to increase the generator RPM by a factor of 50. In 1891 Poul La Cour of Denmark developed superior aerodynamic blades that achieved higher rotor speeds making electrical power generation quite practical. These machines were used extensively until the close of World War I when fossil-fuel steam plants became preferred. In 1903, Inventor Charles G. Curtis and developer Le Roy Emmet made a significant advance in the capacity of steam turbines.

The development of bulk-power, utility-scale wind energy conversion systems was first undertaken in Russia in 1931 and operated for two years on the Caspian Sea. Experimental wind plants were tried in US and Europe from 1935 until 1970 but failed to be practical.

The Arab Oil Crisis of 1973 saw a dramatic spike in oil prices and created a renewed demand for sustainable energy sources. Government funding was devoted to the development of multi-megawatt turbines. From 1974 to 1981, the U.S. Federal Wind Energy Program saw many small, large and innovative systems developed and tested. In the early 1980's the Wind Energy fund was diverted to provide energy tax credits for broad-based private wind turbine technology. Between 1973 and 1986 the commercial wind turbine market evolved from small domestic and agricultural applications to interconnected wind farm utility scale applications characteristic of California wind-farm installations. 17,000 machines were installed between 1981 and 1990. California was the bright spot for the energy tax credit program because of its high coastal winds over coastal its hills. Meanwhile, the large multi-megawatt turbines suffered from political impatience that would not allow for adequate development time. On the other side of the Atlantic, Danish firms made major commercial advances offering three-bladed rotors based upon the Gedser mill design with modernized with light-weight fiberglass blades. By 1986 the Danes had captured 50 percent of the US market. Installations in Europe and Asia grew steadily during the 1980's and 90's.

Improvement is wind turbines have continued. In 1978, one kilowatt-hour cost $1.00 and by 1998 had dropped to $0.05. Hardware costs have dropped below $800 per kilowatt of installation. Wind energy is continuing on its path to becoming the most efficient electric generating technology. Leading wind electric turbine companies include Vestas, GE, Gamesa, Enercon, Suzlon, Siemens, Accoina, Goldwind, Nordex, and Sinovel. Wind turbine electric energy is proving itself to be a viable technology; however, the technology is limited to geographical areas that have consistent wind currents. This limitation suggests that only a small fraction of electric power requirements are likely to be met by wind turbine electric generation.

Wind Electric Glider technology is a unique alternative to wind turbine electric generation. The first patents for Wind Electric Glider or Kite technology date back to the 1970's. The Worcester Polytechnic Institute in Massachusetts launched a Kite Power Team in 2007 to study kite-based power generation. Glider is a more accurate term as the system launches a tethered glider 1000 to 1200 feet in the air and uses the force on the tether to actuate an electric generator. The system requires only a small fraction of the force generated in the lift to retract the tether, thus providing a significant net force gain. The tether actuates a flywheel that drives a generator to produce a constant electrical delivery.

Wind Electric Glider technology is compelling because while ground based wind turbines capture intermittent wind currents, a Glider at 1000 feet and above typically captures 20 MPH winds and greater around the clock anywhere on the globe where there is open space.

New venture company Highest Wind in the New Hampshire seacoast area is developing a value priced system that is well suited for farms and various commercial applications. This system is well suited to remote areas and certainly third-world locations.