Energy Resources
Energy policy
The government of India has formulated an energy policy with the objectives of ensuring adequate energy supply at a minimum cost, achieving self sufficiency in energy supplies and protecting environment from adverse impact of utilising energy resources in an unjudicial manner. The main features of the policy are:
(i) accelerated exploitation of domestic conventional energy resources—oil, coal, hydro and nuclear power,
(ii) intensification of exploration to achieve indigenous production of oil and gas;
(iii) management of demand of oil and other forms of energy
(iv) energy conservation and management;
(v) optimization of utilisation of existing capacity in the country; (vi) development and exploitation of renewable sources of energy to meet energy requirements of rural communities;
(vii) intensification of resources and development activities in new and renewable energy resources;
(vii) organisation of training for personnel engaged at various levels in the energy sector.
In the short term, the energy policy concentrates on development of domestic conventional energy resources along with demand management without adversely affecting economic growth. In the medium term, energy conservation and improved energy efficiency will improve the position while in the long term development of technologies to exploit resources of thorium as well as new and renewable ones on a large scale will be undertaken.
Classification of Energy Resources
1. Commercial Fuels — Eg. coal, lignite, petroleum products, natural gas and electricity.
Non-Commercial Fuels — Eg. fuelwood, cowdung, agricultural waste.
2. Conventional Reassures — Eg. fossil fuel (coal, petroleum & natural gas), water and nuclear energy.
Non-Conventional Resources (or Alternate Energy) : Eg. solar, bio, wind, ocean, hydrogen, geothermal.
3. Renewable Resources — Renewable resources of energy are those natural resources which are inexhaustible (can be replaced as we use them) and can be used to produce energy again and again. Examples are: solar energy, tidal energy, geothermal energy, wind energy, water energy and bio-energy. Atomic minerals are also inexhaustible sources of energy when used in fast breeder reactor technology. However it has the problem of waste disposal and pollution control.
Non-renewable Resources — Are those natural resources which are exhaustible resources and cannot be replaced once they are used. Examples are fossil fuels, such as coal, oil and gas, which together supply 98% of the total world energy demand today.
Coal
Coal is the prime source of energy and accounts for about 67 percent of the country's commercial energy requirement. It is indispensable in metallurgical and chemical industries. Thermal power produced from low-grade coal accounts for 52 per cent of total installed generating capacity of electricity in the country. About 85 percent of total traction capacity with the railways is in the form of steam locomotives.
Coal consists of volatile matter, moisture and carbon besides ash content. The coal deposits in India belong to Gondwana and Tertiary phase. About 98 percent of the coal resources belong to the Gondwana age. Nearly 75 percent of the coal deposits are located in the Damodar River Valley. The places well associated with these deposits are Raniganj in West Bengal, and Jharia, Giridih, Bokaro and Karanpura in Jharkhand. The other river valleys associated with coal deposit are the Godavari, Mahanadi, Son and Wardha. Other coal mines areas are in the Satpura range and in Chhattisgarh plains of Madhya Pradesh. The coalfields of Singareni in Andhra Pradesh, Talcher in Orissa and Chanda in Maharastra are also very large.
The coal mining industry in India was started at Raniganj in West Bengal in 1774. The coal mining was nationalised in 1972-73 to avoid exploitation of labour. The production is now organised through Coal India Ltd., a joint venture of central government and Andhra Pradesh government.
Reserves and Production : The GSI, as on 1 January 1996, have put the country's coal reserves (upto a depth of 1200 m) at nearly 2,01,953.70 million tonnes. Of these, about 27 percent are of coking variety and 73 percent of non-coking variety. Because of the limited availability of coking variety, its use is being limited to metallurgical purposes whereas non-coking coal available in the country is generally suitable for power generation. The major states known for coal reserves are Jharkhand, West Bengal, Madhya Pradesh, Orissa, Andhra Pradesh and Maharashtra.
Classification of Coals — Depending on the relative proportions of fixed carbon, moisture and volatile matter the coal is classified, from high to low rank, as follows: (i) Anthracite, (ii) Bituminous; (iii) Senic Bituminous, and (iv) lignite or brown coal.
Coals are also classified according to percentage of volatile matter into two types.
(i) Low Volatile Coal — It has a low percentage of volatile matter, between 20 to 30 with relatively lower moisture content and is generally known as coking coal. These have good coking properties with ash content of up to 24 percent and with or without benefication are used for manufacture of hard coke required for metallurgical purposes.
(ii) High Volatile Coal — It contains more volatile matter, over 30 percent with moisture as high as 10 percent and is free burning coal mainly suitable for steam raising. It is commonly known as non-coking coal and is used in industries for general heating and steam raising in thermal power generation, in steam locomotives, industries and as domestic fuel.
Lignite : Lignite, also called brown coal, is a low grade inferior coal containing much moisture. On exposure, it disintegrates easily and therefore, before use, it is transformed into briquettes. It is mainly used for thermal power generation, as industrial and domestic fuel, for carbonisation and fertilizer production.
The Indian lignite has less ash content than coal, and is consistent in quality. Important deposits of lignite occur in Tamilnadu, Pondicherry, Uttar Pradesh, Kerala, Rajasthan and Jammu & Kashmir. Lignite reserves in the country are estimated at around 27,400 million tonnes. The deposits at Neyveli in Tamilnadu constitute the country's 90 per cent of the lignite reserves. The mines, however, suffer from the artesian structure and constant pumping of water is a formidable task. But the location of these deposits is a boon for Tamilnadu. It produces 600 mw of thermal power. The industrialization of the State depends considerably on the thermal power generated at Neyyveli lignite field. Annual production in this largely open cast mine is 6.5 million tonnes.
Problems of Coal Mining
(i) India's reserves of metallurgical coal are limited. In spite of this, the recovery of superior grade coal suitable for coke manufacture continues to remain low, about 70 to 80 per cent. It can be increased by mechanising the mines.
(ii) Majority of coal deposits are situated in the eastern and central parts of India whereas the thermal power stations and other consumers are widely dispersed, necessitating long distance transportation of coal.
(iii) Since majority of coal mines are on small scale, they use crude methods of production and hence the per capita production is not only low but cost of production also goes high.
(iv) Large quantities of impurities which are allowed to remain with coal reduce its quality besides adding to high cost of transportation and deterioration of the environment. It can be avoided by washing the coal.
(v) A large amount of coal is just wasted, being discarded as slack coal, which can be avoided if coal powder is converted into briquettes.
(vi) Power shortage particularly in the DVC area, non-availability of explosives and labour unrest are some of the other serious problems faced by the industry.
Conservation of Coal
The coal resources of India are poor, both in quality and quantity, and this situation is aggravated due to the misuse of good quality coal like burning in transport and industries, small reserves of metallurgical or coking coal which may not last long, selective mining leading to large waste of raw coal, frequent fires in mines and unsystematic method of extracting coal. It is therefore essential that coal must be conserved and used selectively.
Coal conservation is ensured by maximum recovery of in situ reserves of coal. Difficult geomining conditions prevailing in coal bearing areas has necessitated the introduction of some latest suitable technology for exploitation of such deposits from coal conservation and also safety point in view. Some other coal conservation methods being used or may be adopted are: (i) reservation of coking coal for use only in metallurgical industry and in no case or used in minimum for steam generation, in transport or other industry; (ii) upgradation of II and III grade coal by washing and blending it with I-grade coking coal and then use in metallurgical industries; (iii) selective mining should be effectively stopped; (v) burning high ash content coal by fluidised bed composition; (vi) smokeless coal for domestic use by carbonisation; (vii) use of slack or powdered coal by briquitting (binding with tar or tar-lime mixture); (viii) oil substitution by coal gasification or liquifaction by Fischer Tropsch Synthesis; (ix) pit head coal processing; (x) magneto-hydrodynamics (MHD)- direct conversion of heat, produced by burning coal, into electricity; and (xi) slurry transportation of coal to reduce transportation costs.
