To learn how wind energy is converted to other forms of energy, you must be familiar with the term windmill. Wind energy is known as one of the cleanest forms of electricity production. The windmill is a device for tapping wind energy using sails mounted on its rotating shaft.
These sails are also called vanes or blades. Well, in this reading, we’ll explore what a windmill is, its applications, parts, diagrams, types, and how it works. We’ll also explore its advantages and disadvantages.
What Is Windmill?
A windmill is a structure that converts wind power into rotational energy through its sails, used specifically for grain milling, pumping (windpumps), and power generation (wind turbines). Many other applications can be designed to use wind energy.
The windmill has its sails mounted at an angle or is given a slight twist so that the force of the wind against them is divided into the plane of the sails, and the wind imparts rotation. So,
A windmill can be defined as a machine that converts the kinetic energy of the wind into mechanical energy, as all the blades of the windmill always rotate in a clockwise direction. wind power was first harnessed by sailors, who were able to know the lift and harness wind’s power through sails.
This knowledge led to the development of the vertical-axis sail-type windmill. It is used by the ancient Persians and Chinese for pumping water and grinding grain.
Applications
Just as earlier stated, the applications of the windmill are used for milling grains, water pumping, and oil extraction from its seeds. The main purpose of windmills today is to convert wind energy into electrical energy, and this electrical energy is further used to power end applications.
Windmills are old technology that are used to mill grains into flour to drive machines or move water. People used the term windmill interchangeably with wind turbine. Wind turbines convert wind energy into electricity by turning a turbine.
Related: What is wind turbine? its Diagram and How it Works
Components of Windmill
The components of a windmill include blades, rotor, anemometer, and tower.
- The blades are one of the essential components of the windmill; they control the functioning of rotor speed.
- The rotor: it approximately took 20% of the device cost, including the blades that convert the wind energy to low-speed rotational energy.
- Generator: It took about 34% of the wind turbine cost, including the electrical generator, control electronics, and most likely gearbox (e.g., planetary gearbox), adjustable-speed drive, or continuously variable transmission. These wind turbine components are responsible for converting the low-speed incoming rotation to high-speed rotation suitable for generating electricity.
- Surrounding structure: it is approximately 15% of the windmill cost and includes the tower and rotor yaw mechanism.
- An anemometer is used for measuring the wind speed.
Diagram
Types of Windmills
The various types of windmills are vertical axis windmills and horizontal axis windmills.
The panemone windmill is the first practical windmill using sails that rotates in a horizontal plane. A similar type of horizontal windmill with rectangular blades is used for irrigation.
The horizontal-axis or vertical windmill is due to the plane of the movement of its sails. Below are the four types of horizontal axis windmill:
- Post mill
- Smock mill
- Tower mill
- Fan mill
How Does WindMill Work?
The working of windmills is less complex and can be easily understood. Conventionally, windmills are designed with three blades after various research of the best-suited amount of blade.
The blades come in contact with the wind, which causes the blades to move along with the shaft. This is what produces the energy through the generator. This generator converts mechanical energy into electrical energy.
Windmills are not designed to produce electrical energy but use mechanical energy to grind grain in grist mills. Vertical windmills, which are used in rural America or Holland, rotate along a horizontal axis using sails of sailcloth.
The rotational force (torque) moves through gears to rotate a millstone. This is why it can be used for grinding grain, driving a shaft to pump water, producing paper pulp, and running a reciprocating saw.
Related: What is Turbine? its Diagram and How it Works
Advantages and Disadvantages of Windmills
Advantages:
Below are the benefits of windmills in their various applications:
- For horizontal axis windmills with a tall tower, the base gives access to the stronger wind in sites with wind shear.
- High efficiency because the blades move perpendicularly to the wind, receiving power through the whole rotation in HAWT.
For vertical axis windmills
- They produce electricity in any direction
- Low production cost when compared to horizontal-axis wind turbines.
- A strong supporting tower is not required
- Easy to transport from one place to another
- Low maintenance cost.
- Can be installed in urban areas.
Disadvantages
Despite the good advantages of these types of windmills, some limitations still occur. Below are the disadvantages of windmills.
For horizontal axis windmills:
- Massive tower construction is required.
- Components like the gearbox, rotor shaft, and brake assembly are being lifted into position.
- Downwind variants suffer from fatigue and structural failure.
For vertical axis windmills:
- Efficiency is very low compared to HAWT.
- High vibration is experienced.
- Noise pollution is created.
- Due to vibration, bearing wear increases, resulting in high maintenance costs.
- The initial push to start is required.
Conclusion
Windmills are the purest and cleanest way of generating electrical power. it is a structure that converts wind power into rotational energy through its sails, used specifically for grain milling, pumping (windpumps), and power generation (wind turbines). That is all for this article, where the definition, applications, components, diagram, types, and working of a windmill are discussed. You also learned the advantages and disadvantages of windmills.