When I get asked about what I do for a living, I typically respond with the same answer, ‘I’m a Marketing Manager for a wind turbine manufacturer’ and I’d say about 70% of the time the first thing that comes out of that person’s mouth is some variation of ‘Oh you mean those large windmills?’ When this happens I always feel the need to explain what the difference is between a windmill and a wind turbine. So here’s a look at the differences with a little history lesson about the evolution from windmill to wind turbine.
NOTE: Please feel free to pass this along to your friends and family if you work in my industry and get asked the same thing too.
The Evolution from Windmill to Wind Turbine:
Throughout history, man has harnessed the wind in many different ways. The first wind energy devices were sail boats used many thousands of years ago. Over the centuries techniques improved, and early wind mills were built by the Persians as early as 500 A.D.
These first windmills were used for pumping water and milling grain (thus the term windmill). Vertical axis windmills were also invented very early on by the Chinese, with some early recorded units dating back to 1219 A.D. The island of Crete in the Mediterranean started using early windmills for pumping water for crops and livestock before 1300 A.D.
Until the turn of the 20th century, almost all wind power was used for pumping applications. The familiar Halladay pumping windmill of the mid 19th century is the most recognizable design in wind power to most people (remember seeing one in Wizard of Oz?). These windmills had steel blades with relatively small rotor diameters, with tails to help orient them into the wind. Over six million of these were installed in the United States alone. These windmills were the natural precursor to electricity generating wind turbines.
In 1888, the first large electricity producing wind turbine was built by Charles Brush, in Cleveland Ohio. The wooden blade system was 17 meters (60 feet) in diameter, used a step-up gearbox with a ratio of 1:50, and turned a DC generator at 500RPM. It could produce 12 kW – with only a 40 foot in diameter 3-blade rotor can produce.
By the early 1920s, a market was born for generating small scale electricity, typically under 5kW, across rural North America, where the power grid hadn’t made inroads yet. These small turbines typically used small DC generators spun by modified aircraft propellers. These were often used for lighting and radio operation, in remote farms and rural areas.
By the 1940s, rural electrification and the spread of the electrical grid became the norm, so the demand for small wind power all but disappeared.
Fast forward to present day, and many countries are now trying to make the shift back to renewable energy sources in order to minimize environmental and health impacts.
For more information on the economic impact of wind turbines, check out our blog post on the subject.