Wind Power is the conversion of energy of wind in to a useful form, by making use of wind turbines. Wind energy when gathered by wind turbines produces energy which can be used for many purposes.
Harnessing the wind for energy is one of the oldest methods of producing energy. Historically wind energy was used to propel sailing ships, to pump water or grind grain. But nowadays wind turbines are used to produce electricity, either for personal use or for contribution to a utility power grid.
Today, wind energy is one of the fastest-growing energy technologies. Wind turbines with strong, steady winds can cost-effectively generate electricity with no pollutants.
For Environment lovers wind energy is favored as it is widely distributed, renewable and has very low greenhouse gas emissions. Wind energy is widely accepted as it is free to use and unlike solar electric power and Micro-Hydro electric power, initial installation charges are quite low.
How wind Energy is generated Sun is the source of wind energy. Wind is a form of solar energy and is the result of the irregular heating of the atmosphere by the sun, the irregularities of the earth’s surface, plus rotation of the earth. Because of this the air near the surface in tropical regions is heated more than the air near the surface of the Polar Regions. This shows the way to the movement of air due to changes in its density and pressure in the atmosphere.
This air movement is the primary cause of the winds. Storing Electricity from Wind Turbines Wind is very beneficial but it does not provide a constant or continuous input for electricity production.
Because of this, power produced from wind turbines should either be used straight away either locally or within a regional grid, or stored for later use using batteries, or grid storage techniques. Grid storage methods capture the energy from the wind turbines and can let go that energy during off-peak periods. Wind is an important source of power generation medium as it does not create any emissions and is renewable. Work is being done to improve the efficiency of wind turbines.
Although at the beginning wind turbines were somehow inefficient, but people learned to develop them efficiently and to make the windmills a desirable source of energy. Wind turbine — components:
- Gearbox — Gear box connects the low and high-speed shaft to each other
- Blades — wind blowing over the blades causes them to lift and rotate
- Hub — the sphere object used to mount the blades on
- Generator — Generator creates at least 60-cycle AC electricity
- Tower — Tower is the metal pole the turbine operates from. Tower is at least 100 feet off the ground so that the turbine can capture the least turbulent wind
- Rotor hub — Rotor hub is the hub and the blades together
- Yaw drive — Yaw drive is required only for an upwind turbine; it keeps the rotor facing the wind
- Yaw motor — It provides power for the yaw drive
- Nacelle — Nacelle sits on top of the tower and clings to the gear box
- Low-speed shaft — It is turned by the rotor at a rate of 30 to 60 rotations every minute
- High-speed shaft — It connects to the generator and drives it
- Anemometer –Anemometer is used to measures the speed of the wind Science behind the generation of wind power
Wind power is generated by transferring the wind energy into a functional form of energy, such as by using wind turbines to create electricity, through wind mills for mechanical power, by making use of wind pumps for pumping water or drainage.
Let’s study how wind turbines and wind power for homes are used to generate electricity? When wind moves over the turbine blades, it causes a lift. The lift makes the blades rotate and consequently rotate the shaft. The rotating shaft starts moving magnetic field in the generator, which generates electricity. Therefore the rotational motion of the wind turbine blades is converted to electricity.
The generator uses electromagnetic induction to generate electricity, which can either be consumed right away or can be stored for a later use. A source of energy loss in this arrangement is friction between the drive system, which may include a gearbox and the generator itself. For reducing the friction and increasing efficiency, a gear-free annular generator can be very helpful as it will help reducing the stress and wear on the turbine’s moving parts.
Generation of wind power for homes primarily depends upon the speed of the wind and the amount of blade surface exposed to the wind. Another factor which affects its efficiency is the wind turbine blades. Shape of wind turbine: The shape of wind turbine blades highly influences their rotation.
The blades are available in many shapes like flat, rectangular ones, the wing shaped ones and the ones with edges tapered to a thin line or edges rounded. But in the horizontal axis wind turbines, the wing shape has proved to be the most efficient one and in the vertical axis wind turbines the best output is given by the flat ones and the ones with both edges rounded. Length of wind turbine blades:
The length is also an important factor. If a blade is longer, it can catch more wind with every rotation. Material for Wind turbine Blades: In earlier times wood was used to make the windmill blades. These days wood is still used but lighter wood material is used to carve the blade and faster speed rotation.
The latest blade design is made of fiberglass and epoxy resin, its curvature like tip which allows it to catch low wind speeds makes it exclusive. Other material used for turbine blades is carbon fiber which is light in weight and has a razor sharp edge that allows it to exactly cut through the wind and makes it nearly silent. This material is widely preferred and is used in the majority wind turbine machines sold today. Number of Blades: The old wind turbines normally had 4 very heavy blades. After the research on the number of blades to be used, it was found that more blades seemed to raise noise and slow down the rotation of the turbine’s propeller formation. At present, the most recent windmills are equipped with two or three blades.