Did you know that the first practical wind turbine generator dates back 74 years to 1941? It was then that Palmer Putnamof Vermont demonstrated his device. His 1.5 MW wind turbine had blades 66 feet in length, and in 700 hours of operation, produced nearly 300,000 kilowatt hours.

Innovators were working on wind turbines between the World Wars, mostly for rural areas in Canada and America where people had difficulty getting power. However, it was Putnam who realized that to generate more power, more efficiently, location and high wind speeds were vital. When searching for his ideal location, Putnam looked for wind speeds in excess of 30 mph. He also wanted to be able to supply alternating current to the grid without the losses incurred by converting direct current to alternative current.

According to his patent, he found his “advantageously exposed” location in that of Grandpa’s Knob, a 1976 foot high forested summit with a rocky base. During the winter of 1940-1941, workers built the 120 foot (36 meter) tower and turbine. The wind turbine featured just two steel blades, each weighing 7.5 tons each and were 66 feet (20 meters) long —bigger than the wings of all but a handful of bombers flying at the time. The turbine was designed to operate in wind velocities between 30 and 60 miles per hour and to withstand gusts stronger than 140 mph.

Today, there are more than 2,700 electric power generating facilities (i.e. wind farms) producing 4.1 million megawatt hours. Wind power now provides 4.5 percent of the U.S. electricity production. Siemens is building the world’s longest blade that is 74 meters long, nearly 243 feet, the length of an A-380 Airbus airplane,