Wind turbines and windmills may look similar, and many people confuse the two terms, but in fact, they are two very different things.
Do you know the difference? If not, then this beginner's guide will explain the differences (and similarities) in terms that anyone can understand.
In less than 5 minutes, you'll be able to tell a wind turbine from a windmill from a mile off, and even impress your friends with your new knowledge!
Contents
A modern wind turbine is a device that converts the kinetic energy of wind into electrical energy.
Wind turbines are typically used in conjunction with other forms of renewable energy, such as solar panels, to create a more reliable and consistent source of green power.
A good domestic wind turbine can generate power for an individual house (or boat). Large-scale wind farms generate renewable energy that can power thousands of homes.
There are two main types of wind turbines: horizontal axis and vertical axis. The vast majority of modern wind turbines have a horizontal axis, meaning that the blades rotate around a vertical shaft.
Vertical axis turbines are less common, but they have the advantage of being able to be located closer to the ground, making them more accessible for maintenance and repairs.
Wind turbines work by using the kinetic energy of wind to spin a generator that produces electricity.
The curved blades of a wind turbine generate lift and a difference in air pressure on each side of the blade, which causes them to rotate.
The force of the wind turns the wind turbine blades around a central shaft, which is connected to a gearbox. The gearbox increases the speed of the rotation and transfers the energy to a generator. The generator then generates electricity that can be used to power homes and businesses.
Wind turbines can be located offshore or onshore.
An onshore wind farm is typically located in rural areas where there is a consistent source of wind.
An offshore wind farm is located a few miles out at sea, where the wind blows at stronger and steadier speeds.
Wind farms are becoming increasingly common, as they offer a more efficient and environmentally friendly way to generate electricity than using fossil fuels such as coal or natural gas.
A windmill is a machine that converts the energy of wind into rotational energy by means of vanes called sails or blades. Centuries ago, windmills usually were used to mill grain, pump water, or both.
The first windmills were developed in Persia and China more than 1,000 years ago. Windmills later spread to Europe, where they were used for grinding grain and pumping water.
By the 18th century, windmills were also being used in America to grind flour and transport water. In the late 19th century, windmills were used to generate electricity in Europe and America.
Windmills are classified according to the way their vanes are mounted on the main shaft. The three most common types of windmills are post mills, smock mills, and tower mills.
Post mills have the vanes mounted at the bottom of a wooden or metal post.
Smock mills have the vanes mounted on a wooden or metal framework that resembles a smock, a type of loose-fitting shirt.
Tower mills have the vanes mounted at the top of a tall tower.
The sails of a windmill are angled so that they catch the wind blowing in from the side. The force of the wind turns the sails around the main shaft, which is connected to a large gearwheel.
The gearwheel turns a second, smaller gearwheel that is connected to the millstone. The millstone grinds grain into flour or meal.
Windmills and wind turbines share an obvious common factor - that they use blades to harness wind power. But there are several key differences between them.
The main difference between a wind turbine and a windmill is their purpose. Wind turbines are used to generate electricity, while windmills are used for pumps or grinding grain.
Wind turbines work by using the wind to turn blades that spin a generator, which produces electricity. Windmills work by using the wind to turn blades that pump water or grind grain.
Wind turbines are usually much larger and higher than windmills, with thinner blades, and often operate together in larger installations. Windmills are typically smaller, but have thicker blades, and generally require less power to operate.
Wind turbines need to be located in areas with strong and consistent winds, such as on top of hills or in open fields. Windmills also only work when the wind blows, but they can only be located onshore.
Wind turbines are a relatively new technology, while windmills have been used for centuries.
So, while wind turbines and windmills both use blades to harness the power of the wind, they are designed and used in different ways.
Wind energy is a type of renewable energy that uses wind to produce electricity.
Wind energy is a clean, emission-free source of electricity, making it a very attractive option for those looking to reduce their carbon footprint.
Wind energy is the energy that comes from the wind. This can be harnessed using wind turbines, which convert the wind's energy into electricity.
Wind power is the term used to describe the amount of electricity that is generated by a wind turbine.
The name "windmill" is derived from the fact that these early machines were powered by the wind and were used to mill grains, wheat, or paper.
Wind power is generally recognized as one of the cleanest forms of renewable energy. But just like any other energy source, it isn't perfect.
Wind turbines and windmills are two very different technologies that are commonly (and incorrectly) confused.
They both use blades to convert wind power into clean energy, but turbines produce electricity whereas windmills are used to directly produce mechanical energy.
These can have various applications, but the energy produced must be used locally to the windmill itself.
To find out more about whether a domestic wind turbine could help you reduce your energy bills, check out our guides on the cost and benefits of a wind turbine, and the correct way to calculate its mean power output.
And now, if you hear someone use the terms windmill and wind turbine incorrectly, you can put them right (politely of course!)