Which fuels can be obtained by microbial processes ? Why is it necessary to increase the use of such fuels ?

Explanation

(i) Various fuels like methane , ethanol , hydrogen gas , etc. are fuels obtained by microbial processes.
(ii) It is necessary to increase the usage of such fuels so as to reduce exhaustion of fossil fuel resources .
(iii) Most of these fuels can be obtained by anaceobic decomposition of waste products such as domestic waste, agricultural waste, etc. Hence , their cost of production is relatively very high .
(iv) When methane is burned , comparatively lower amounts of smog forming pollutantants , toxic air and gases are generated.
(v) Ethanol is a clean fuel . It is obtained during fermentation of molasses by Saccharomyces.
(vi) Hydrogen gas is considered as the fuel of future since it does not emit any harmful substances on buring and is produced by bio - photolysis of water .
(vii) As a result , it is necessary to increase the use of fuels obtained by microbial processes.
Types : Ethanol - biologically produced alcohols , most commonly ethanol and less commonly propanol and butanol are produced by the action of microorganisms and enzymes through the fermentation of sugar or starch cellulose.
(ii) Bibutanol also called biogasoline is often claimed to provide a direct replacement for gasoline.
Biogas is methane produced by the process of anaerobic digestion of organic material by anerobea.