Windmills

Originally published in the Fall 2004 issue of the Iowa Barn Foundation Magazine.

Written by Howard P. Johnson, Anson Marston Distinguished Professor in Engineering Emeritus, Iowa State University.

Windmills designed to provide power to pump water appeared in New York in the 1860's. In 1854, Daniel Halladay, after whom the windmill company was named, patented a mill which would face the wind and be self-governing in high winds. A windmill was placed over many farm wells in Iowa after 1900.

By the turn of the century, 56 firms competed for sales of mills. Windmill models common in the Middle West were Halladay, Aermotor, Eclipse, Dempster, Baker, Challenge, Star, and Elgin.

The first windmill towers were built from wood. By 1900, steel frame towers with various brace designs were constructed around four angle steel legs. Mills were typically 20 to 40 feet high to the wheel center.

LaVerne W. Noyes, an 1872 graduate of Iowa State College, supported development of the Aermotor windmill as an inventor and industrialist. Thomas Perry, an employee of Halladay's U.S. Wind Machine and Pump Company, tested 61 wheels. His tests defined speed, angle, curvature, and amount of sail surface to design a scientifically based wheel. Since his company chose not to redesign their wheels, Perry joined Noyes in 1883 to perfect a self-binding harvesting machine. Perry and Noyes also built a new windmill with sheet steel blades which combined best pitch, featuring, and turns per stroke. Perry designed the Aermotor; Noyes, who had over 50 patents, provided manufacturing support. In 1888, 45 Aermotors were sold; in 1892, 20,000 were sold. By the turn of the century, Aermotor had half the market. The company introduced the all-steel tower in the 1890's. Over 800,000 Aermotor windmills had been in service by 1950; half were in service more than 40 years.

Because of rural electrification, sales of windmills dwindled to less than 10,000 per year by 1956. LaVerne Noyes supported construction of appropriately named Lake LaVerne on the Iowa State University campus.