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WIND POWER GENERATION
ABSTRACT:
Wind is energy clean and plentiful source of energy. All renewable energy (except tidal and geothermal power), ultimately comes from the sun The earth receives 1.74 x 1017 watts of power (per hour) from the sun. This paved path for non-conventional sources. Of all the renewable energy sources; the one that has matured to the level of being a utility generation source is wind energy .It is estimated that wind potential is 1.6*10 7MW which is same as world energy requirement. But the only problem is that wind speed is highly fluctuating. So many problems arise during power generation. So we mainly concentrate on the problems occurred during generation and how they can be rectified. The problems faced are due to local impacts and system impacts. Local impacts deal with the impacts that occur in the vicinity of the wind turbine or wind farm. System impacts are the impacts that affect the behavior of the system as a whole. Using modern power electronics and special type of wind turbines that suit to the conditions can solve local impacts. Designing turbines to withstand voltage variations of certain magnitudes can rectify system impacts to some extent. Controlling the rotor speed by gear mechanism can rectify problems due to high wind or computer aided techniques.
NON-CONVENTIONAL SOURCES:
While fossils fuels will be the main fuels for the thermal power there is a fear that they will get exhausted eventually in next century therefore many countries are trying systems based on non-conventional and renewable sources. These are Solar, Wind, Sea, Geothermal and Biomass. Because if we take solar power on earth it is 10 6watts.The total world demand is 10 13 watts, If we utilize 5% of the solar energy, it will be 50 times what that world require. If we consider the wind potential it is estimated to 1.6x10 7M.W, which is same as world energy consumption. So the development of non-conventional energy source is very; economical. While fossils fuels will be the main fuels for the thermal power there is a fear that they will get exhausted eventually in next century therefore many countries are trying systems based
TYPES OF WIND TURBINES
There are two basic types of wind turbines: horizontal Axis wind turbines and vertical axis wind turbines. Horizontal axis turbines (more common) need to be aimed directly at the wind. Because of this, they come with a tail vane that will continuously point them in the direction of the wind. Vertical axis turbines work whatever direction the wind is blowing, but require a lot more ground space to support their guy wires than horizontal axis wind turbines.
Source: Ontario Ministry of Energy
COMPONENTS OF WIND ENERGY SYSTEMS:
The basic components of a typical wind energy system are shown in figure below.
Components of wind energy syst
These basic components include:
 A rotor, consisting of blades with aerodynamic surfaces. When the wind blows over the blades, the rotor turns, causing the generator or alternator in the turbine to rotate and produce electricity.
 A gearbox which matches the rotor speed to that of the generator / alternator. The smallest turbines (under 10kW) usually do not require a gearbox.
 An enclosure, or nacelle, which protects the gearbox, generator and other components of the turbine from the elements.
 A tail vane or yaw system, which aligns the turbine with the wind.
 If you plan on building a horizontal axis wind turbine, you will need a tower on which to mount the turbine (vertical axis turbines are usually built on the ground).
Several types of towers are available:
 Guyed lattice towers, where the tower is permanently supported by guy wires. These towers tend to be the least expensive, but take up a lot of space on a yard. A radi broadcast tower is a good example of a guyed lattice tower.
 Guyed tilt-up towers, which can be raised and lowered for easy maintenance and repair.
 Self-supporting towers, which do not have guy wires. These towers tend to be the heaviest and most expensive, but because they do not require guy wires, they do not take up as much space on a yard.
An important factor in how much power your wind turbine will produce is the height of its tower. The power available in the wind is proportional to the cube of its speed. This means that if wind speed doubles, the power available to the wind generator increases by a factor of 8 (2 x 2 x 2 = 8). Since wind speed increases with height, increases to the tower height can mean enormous increases in the amount of electricity generated by a wind turbine.