A windmill has the same basic form pretty much all of the time: it consists of a central wheel which is equipped with sails or blades that harness the wind’s energy.
As the wind hits the sails, it turns the wheel and this can form a variety of functions, from grinding corn to generating electricity.
Windmills are wonderfully versatile, and clean and green sources of renewable energy, and there are many different types. Here, we explore the key types of windmill and what they are used for.
Windmills used for grinding corn. These windmills, in their earliest form, originally had a horizontal shape in that they rotated around a horizontal plane. There were various other forms that developed, however, including post and ‘smock’ shaped windmills which rotated around a vertical axis which became more common as time progressed. The smock shaped windmill is the type that is used in Amsterdam, for example, with its attractive front facing turbine. These windmills provided a way of harnessing energy to turn a central stone, which could be used to grind corn, wheat and similar grains into flour. This effortless grinding mechanism replaced more back breaking ways of grinding corn and wheat into flour by hand using a heavy millstone or by means of a treadmill powered by the walking motion of humans or animals. Corn and other cereals could also be ground using a similar structure known as a water mill. Watermills have sails like windmills, but they are placed in running water such as a river – it is thus the motion of the water rather than the motion of the wind which turns the sails.
Wind turbines used for generating electricity. An increasingly common site in the present day, metal wind turbines are elegant structures that are used to harness the power of the wind to generate electricity. They consist of a (usually) three bladed turbine which is placed in a windy location offshore or on an exposed location on the land, and which is turned by the motion of the wind. This turns a mechanism which generates electricity by turning kinetic energy (i.e. movement energy) into electrical energy. Usually, several wind turbines are placed together in what is known as a wind farm. Wind turbines are a good way to generate power in a sustainable and renewable way, The land that is used for wind turbines can be used for growing crops or grazing animals at the same time, too, so they do not disrupt the usual way in which land is used for growing food. They provide a good alternative to fossil fuels, which cause a huge amount of pollution and which are endangering the biodiversity of our planet more and more every single day. The energy generated by a wind turbine can be stored – and here it contrasts with ancient windmills which only provided energy that could be used instantly but which could not be stored. The ability to store the electrical energy that is generated by a wind turbine means that even on days when there is not much wind you can still take advantage of the green energy that was produced by your local wind farm.
Wind pumps used for pumping water. The problem of how to move water around – and particularly how to get large amounts of water from a low position to a high position – has fascinated engineers since the ancient times. Hydraulic pump systems are one ancient solution that is still in use today. Another solution to pumping water without a lot of effort and in an efficient way is to use a similar mechanism to a windmill and to use a device that is known as a wind pump. Here, a windmill is used to activate a pump, which can be used to drain agricultural land that has flooded, retrieve water from a deep well, or perform any number of similar tasks. Wind pumps were probably invented in the middle east and they were widely used in the Islamic world in the middle ages. They have since spread worldwide and they are very often used, for example, in the United States for agricultural purposes.
A sustainable solution for our energy needs, which saves us effort. As we seek sustainable and environmentally friendly sources of energy for both the present day and for future generations, windmills and wind pumps appear to be a perfect solution. As you can see from the above, wind mills are a great way to save humans effort by using the natural motion of the wind to perform tasks that would otherwise be very strenuous for us, such as hauling water out of wells and grinding grains. Windmills can also be self regulating so there is no need for them to be controlled by a human being (though, yes, there is also the option to have a human operator using a centrally controlled gearbox to regulate the speed of a windmill). In addition, they do not emit all of the devastating pollutants that are associated with other types of energy generation such as the burning of fossil fuels – coal, oil, and natural gas. Many people also believe windmills to be a charming sight on the landscape – indeed, tourists come from far and wide to view and take pictures of the classic historic windmills in Amsterdam.
Conclusion – Celebrating the power of windmills.
If you live in a windy part of the world, you may already have wind turbines generating part of your electricity. If not, you could take the opportunity now to find out whether this could be a greener, cleaner option for your community. Writing to your government or to the local authorities could be a good way to get the ball rolling with this. Make the argument that green energy is the future, and that wind mills provide a sustainable and very cost effective way to meet your community’s energy needs.