What is wind energy? How is it produced? What are the major conversion systems?
Wind is a kind of solar power that owes its origin to various environmental factors. The uneven earthís terrains get unequally heated by the sunís rays. This makes some region of the earth warmer than the others. The hot air in the warmer regions becomes less dense and light and thus rises up. This upwardly movement of the hot air creates a vacuum which is immediately filled up by cold air from the adjacent cooler realms. This movement of air is called wind and the energy is called kinetic or motion energy. This kinetic energy can be captured and machinated by modern methods to get wind energy. The two most modern wind energy conversion systems are wind mills and wind energy turbines.
Varieties of the conversion systems
Like stated above, the two wind energy generators are deployed to harness wind energy into mechanical power and electricity according to the requirement. Of the two wind energy conversion systems the wind energy turbines are used to generate electricity whereas mechanical power is generated by the wind mills. A detailed view of both the systems will give us a clear idea as to which one of them is more efficient and cost effective.
The basic principle of a wind turbine is very simple. Typically a wind turbine consists of two or thee blades fitted to a rotor. The rotor is connected to a main shaft that spins a generator which produces electricity. Wind turbines meant for generating electricity are usually mounted high at a usual height of 100 feet (thirty meter) from the ground. Wind at such a height is much faster and less roiling, thereby providing a decent output. Wind mills however, depend on the number of blades to give a good output of mechanical energy. Also, the wind speed of a particular area affects the productivity of a wind mill to a great extent. Functionally speaking, windmills can be grouped into various types namely, wind pumps, tjasker etc. Wind pump is basically a wind mill used for pumping water out of a draining land or well. Wind pumps these days are being deployed for the drinking water of cattle and human use also. Tjasker is another type of drainage wind used for raising water for areas where a low head is required. Comparing the two wind energy conversion systems closely gives a clear idea about which one of them is more cost effective and efficient as well.
Advantages and disadvantages of the wind energy systems
Since wind is a free resource, the wind conversion systems are becoming more and more popular by the day. Besides being a free resource, wind is also a clean and pollution free resource that will never contaminate the air with greenhouse gases or air pollutants like the conventional power plants. Fossil fuels like coal and natural gas are required for the conventional power plants that emit acid rains and greenhouse gases resulting in depletion of the atmospheric layers. Being a renewable and free resource wind power will get never get exhausted. So long the sun is shining, wind energy will be there! The wind energy generators are also quite economic as they only need a small fraction of the land (leased by the farmers) and the farmers can earn money throughout the year from this lease. Also the wind turbines are built on ranches in the rural areas, the latter being a suitable wind site.
In spite of all the advantages stated above, the wind power plants pose quite a few disfavors also. The main minus point of wind energy is its intermittent supply. Wind flow is actually an involuntary process and does not meet the requirements always on time. Also the most remotely located areas make the best wind sites and thus electricity is produced far off from the areas it is actually needed at. Even the land required for wind energy plants seem to be partially favoring its other alternative usages that are apparently being more esteemed than electricity production. Thus a technological development and a better wind site together play a vital role in the wind energy renewal process. In spite of all the above stated differences, wind power plant is attaining heights of achievements in this modern era of energy conservation and renewal.