Around 80% of the population lives in rural areas which primarily utilize biomass for their energy requirement. Depending on the agroclimatic zone by diversity and plant productivity the biomass utilization varies in different parts of the country. A large number of laticiferous plants have been reported to yield hydrocarbons which could be converted into petroleum like substances. Initially E. abyssinica J.F. Gmel. Was used by French in Morocco and Italians in Ethiopia. Subsequently, a systematic search was made for renewable sources of liquid fuel. United States Department of Agriculture carried out major surveys in the Northern Regional Research Centre, Western United States, Southern Great Plains and other parts of USA. The present paper describes the use of various biofuel sources in the rural areas of India.



1. INTRODUCTION





1.1 ENERGY SCENE IN INDIA



Energy consumption is an index of a country’s economic development. It has been estimated that if the economic growth rates were to be in the range of 5.5-6%, the energy requirements would register a four-fold increase within the next 20 years. According to the Report of the Working Group on Energy Policy, 1979, it is evident that there has been a steady increase in the consumption of the commercial form of energy (coal, oil and electricity) from 32.4% in 1953-54 to 59.7% in 1978-79 while a similar decrease is noticed in the non-commercial sources of energy (fuelwood, agricultural residues, and animal dung). The steep price hike in the commercial energy forms has started showing serious repercussions on all programmes of development in the country. A further increase in the consumption of commercial forms of energy by about 71.1% during 1987-88 and 86.2% during 2000-2001 AD is likely to aggravate the situation still further (Table 1).



1.2 BIOMASS AS A SOURCE OF ENERGY



Energy sources can be broadly divided into three distinct groups : fossil fuels, fissionable nuclear fuels and non-fossil, non-nuclear energy sources. Inspite of their outstanding virtues, fossil fuels have two insurmountable drawbacks. Firstly, these are non-renewable and thus supply of many such fuels is either approaching exhaustion or getting more difficult to procure due to transport bottlenecks and steep hike in their price level. Secondly, their continued and increasing



use creates environmental problems. Like

fossil fuels, fissionable nuclear fuels also suffer from two serious drawbacks. Their supply from relatively

cheap sources is drying up even for the most advanced countries. Moreover, the production and use of this sources cause a plethora of hazards both to man and his balanced environment on earth.



According to Dr. T.N. Khoshoo, Secretary, Department of Environment, the only alternative appropriate to the socio-economic conditions prevailing in this country is the Photo-synthetic Model of Development. It has been the source of an old, reliable and renewable form of energy, now referred to under a new name, Biomass. This is relevant even for all developing countries, although its extent and nature may vary from one country to another. Out of the total solar energy on earth (3x1024), the plant life utilizes about 0.1% annually, leading to an annual net production of 2x1011 tonnes of organic matter which has an energy content of 3x1012J. The total annual energy use, however, is of the order of 3x1020J. One of the natural assets of our country in the abundant sunshine. The total solar radiation received in India is about 60x1013 MWH, with 250-300 days of useful sunshine per year in most parts of the country. The daily average direct radiation at places in the central part of the country is 5-7kwh/m2. There is thus a vast scope for harvesting solar energy and improvement in photosynthetic efficiency (Fig. 2).



1.3 BIOFUEL SOURCES



Some of the common biomass used are –

1. Fuel wood

2. Cow dung

3. Sawdust

4. Coconut husk

5. Pea nut shell

6. Bagasse of sugarcane

7. Straw

8. Rice hask

9. Culums of pulses

10. Saccharum munja

11. Cajanu s cajan



The cowdung also mixed with wheat straw cold dust in different proportionate to make brickets use of biomass in their raw form results in considerable loss of energy because of uncontrolled burning process. In efficient burning in poor fire place results in smoke in waste full utilization of pressure biomass resources. The fuel wood is used in rural India varies from roots of Caligonum polygonoides (fog.) in western Rajasthan, stem of Calotropis procera in dried climatic zones, dried Euphorbia in semi-arid region, Acacias species, Prosopis, Holoptelia integrifolia.



The improperly dried would results in considerable fuels and smoke.



Energy plantation include fast growing plants which yield biomass on a three year rotation cycle. Some of the plants used for the energy plantation include :



1.4 GOAT AND SHEEP



Crop residues / Weeds/ Neglected Plants

Bagasse

Banana peel/stem

Coconut waste

Coffee waste

Corn stover

Cotton stalks

Groundnut shell

Jute sticks

Maize cobs

Molasses

Rice husk

Rice straw

Farm residues : programme and policies



Forest Waste



Swadust

Wood chips



Industrial Waste



Dairy waste

Distillery effluents/spent wash

Plastic waste

Textile waste



Urban Waste



Solid waste/ city refuse

Liquid waste/sewage



Weeds/Neglected plants



Bermuda grass (Cynodon dactylon)

Calotropis (Calotropis spp)



Other wastes



Energy plantations



Agati (Sesbania grandiflora)

Axlewood (Anogeissus latifolia)

Babul (Acacia nilotica)

Bengali babul (Acacia auriculiformis)

Ber (Zizyphus mauritiana)

Casuarina (Casuarina equisetifolia)

Ebony (Diospyros melanoxylon)

Eucalyptus (Eucalptus spp)

Euphorbia (Euphoriba spp)

Gmelina (Gmelina arborea)

Guayule (Parthenium argentatum)

Israel Babul (Acacia tortilis)

Kadam (Anthocephalus cadamba)

Jojoba (Simondsia chinensis)

Mango trees (Mangifera indica)

Palm trees

Pines (Pinus spp)

Poplar (Populus spp)

Rain Tree (Pithecellobium soman)

Sal (Shorea robusta)

Salai (Boswelia serrata)

Shisham (Dalbergia spp)

Subabul (Kubabul) (Leucaena leucocephala)

Teak (Tectona grandis)

Terminalia (Terminalia spp)



Energy Cropping



Cassava (Manihot esculenta)

Jerusalem artichoke (Helianthus tuberosus)

Mahua flowers (Madhuca indica)

Sugar beet (Beta vulgaris)

Sugarcane (Saccharum officinarum)

Sunflower (Helianthus annuus)



Acacia auriculifomis has specific gravity 0.60 to 0.78 and 4800-4900 kCal/gm it is fotter nitrogen fixer.

Acacia leucopholea (safed babool) has specific gravity 0.78 and 4899kcl/gm.



Acacia nilotica, A. tortilis, A. senegal, Aegle marmelos (bel) has specific gravity 0.91 and 4495kcl/gm.



Albezia lebbec (siris) has a higher calorific value 5163 and low specific gravity 0.55-0.64.



Other short rotation tree include Cassia fistula (Amaltas), Butea monosperna Capparis aphyll, Cassia siamea, Cajurina equisitifolia, Cordia dicotoma, Delbergia sisso, Eucalyptus, tereticornis, Gravellia robosta, Hardwickia binata, Holoptelia integrifolia. Azardiracta indica. Prosopis chinensis, Prosopis juliflora, Sesbenia grandiflora, Salvadora oleoides, Stercularia urens, Temaris aphylla, Terminalia bellirica.



Beside the tree species certain shrubs or annuals are also used for fuel purposes which include Crotolaria juncea, Cymopsis tetragonoloba, sesbnia, Aegyptiaca Calotropis procera, Jatropha curcas. These plants are used directly for burning in the rural areas of the country. Derris indica also yields Karunj oil, Acacia tortilis introduced in Rajasthan is able to grow at 50ºC it is fast growing plant in arid region. A twelve year old plantation of 3x3 mtr. spacing yields 54 tonne/hac. It is ideally suited for extreme conditions similarly Prosopis chinensis also yield 40 tonne/ha/year. Its fast growth for remarkable.



2. CONCLUSION:



A large number of unutilized and underutilized plants have potential for their use in bio-energy plantations and use in rural applications.