Apart from the depleting traditional sources of power such as coal, there are several alternatives which make use of naturally available forces to fulfill the energy requirements of mankind. Read here about one such resource namely the wind power.
Introduction
What do you wish when you hear that energy resources of the world are dwindling while the energy requirements are on the rise? I simply wish if there was a way by which we could produce electricity out of thin air. My academic studies tell me that nothing comes out of nothing and it is against the principle of conservation of energy that such a thing should happen. But the other day I just realized that energy can be produced out of thin air as well. So do I mean to say that I have become a great scientist and reshaped the energy conservation principle? Well unfortunately not, but then here is a way of doing it while preserving the energy laws as well.
Out of Thin Air! Really?
Yes, it is very true that energy can be produced out of thin air but not in the literal sense of the word that is to say not without putting any input to it. The method actually makes use of the energy found in the air when it is blowing at a fast speed. Well you know it by the name of wind but just wait – when I say wind I do not mean that you need winds to be of the tsunami level for it to generate energy.
Just like Tidal Power Plants which we studied earlier we also have energy hidden in the air because air is a fluid like water of course with a few fundamental differences. If you think that this is a new and novel idea, think again. Can you remember how Columbus sailed across the world (I know you were not a crew member but you must have surely read it somewhere). What I mean to point out is that wind energy was extensively used to power ships and boats in the earlier days through the rivers and high seas. So the same energy which can be harnessed to move a boat by hundreds of miles can also be used to power at small electric generator at least.
I see that now you are coming close to the concept of generation of electrical energy through wind power. So basically its all about having a rotor of some kind which rotates in air when the air speed is sufficient so that it can turn an alternator to generate electricity. The figure below shows a crude example of such a wind turbine
A Wind Turbine
How Powerful is “Thin” Air?
Since air is used to generate electricity you might ask how much power flowing air contains. Well it is common sense that the kinetic energy of the air would increase with speed which means that more the speed the more the power available in the air. Rough estimates show that air moving at a speed of 40 kilometers per hour though a channel one square meter across, has an equivalent of nearly 400 watts of electric power. Of course the maximum that is possible to extract out of this is less than two-thirds due to associated losses.
This should give you a rough idea about the amount of power in flowing air and we will learn more about wind power and wind power generation techniques in later articles.
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