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Sources of Energy

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What is a good fuel?

The characteristics of a good fuel are:

(i) It should be farily cheap.
(ii) It should be easily available.
(iii) Its ignition temperature should be well above normal temperature.
(iv) It should be conveniently handled and transported.
(v) It should not produce, during burning, any poisonous materials or irritating fumes.
(vi) Its combustion rate should be steady and controllable.
(vii) It should not leave any residue or ash after burning. 


Why are we looking at alternate sources of energy?

The most convenient and largely developed conventional source of energy are fossil fuels like petroleum and coal. But, these sources are not renewable source of energy and they emit large number of pollutants into the atmosphere.

As the world is evolving, the stock of these resources is depleting. Thus, the future generation will encounter energy-crisis. Hence, we need to look for alternate source of energy. 


What are the disadvantages of fossil fuels?

Disadvantages of fossil fuels are: 

i) Production of oxides of carbon, nitrogen and sulphur causes pollution and acid rain. It affects our water and soil resources. 
ii) These gases also cause many health hazards and are extremely harmful to asthmatic patients. 
iii) Carbon dioxide produced causes green-house effect which is responsible for global warming. 

If you could use any source of energy for heating your food, which one would you use and why?

Cooking gas like LPG or PNG would be preferred. They have characteristics of a good fuel. The ignition temperature, calorific value are apt and has non-pollution characteristics. 


What is a good source of energy?

In general a good source of energy would be one,

(i) which would do a large amount of work per unit mass or volume
(ii) which would be easily accessible.
(iii) which can be easily stored and transported.
(iv) which is also reasonably economical.