(a) Examine the importance of Bio-gas energy in rural areas.

(i) Shrubs, farm waste, animal and human waste are used to produce biogas for domestic consumption in rural areas.

(ii) Decomposition of organic matter yields gas, which has higher thermal efficiency in comparison to kerosene, dung cake and charcoal.

(iii) Biogas plants are set up at municipal, cooperative and individual levels.

(iv) The plants using cattle dung are known as ‘Gobar gas plants’ in rural India.

(v) These provide twin benefits to the farmer in the form of energy and improved quality of manure.

(vi) It is by far the most efficient use of cattle dung.

(vii) It improves the quality of manure and also prevents the loss of trees and manure due to burning of fuel wood and cow dung cakes.

OR 17.(b) Examine the significance of natural gas for industrial usage.

(i) Natural Gas is a very important clean energy resource which is found with petroleum deposits and is released when crude oil is brought to the surface.

(ii) It is used as fuel in power sector to generate electricity.

(iii) It is used for heating purpose in industries.

(iv) It is used as raw material in chemical, petrochemical and fertilizer industries.

(v) With the expansion of gas infrastructure and local city gas distribution (COD) networks, natural gas is also emerging as a preferred transport fuel (CNG).

(vi) It is also used as cooking fuel.