Bioenergy requirements in the short to medium term, however, there are uncertainties concerning the availability of all of the above resource for the long term and in few countries some of them are already used completely (e.g. biomass originating from process waste in Germany). In addition, there will come a point where competition with food crops will limit the availability of land for SRF or other energy crops. It is therefore advisable to look into new biomass resources from the extreme deserts of Rajasthan in India, Sahara and middle east. Calotropis procera could be one such potential candidate which has been studied in detail. In addition to this aquatic plants and micro-algae offer and attractive proposition. In addition, the Bioenergy community must recognize that there will be increased competition for chemicals and polymers from biomass feedstocks as well as for several other traditional industrial products from biomass. It is therefore necessary to develop new concepts, such as bio¬refineries for component fractionation, to satisfy the demand for food, industrial Bio-Products and Bio-Fuels for Bioenergy. Finally, for all feedstocks it is necessary to develop standards supported by a quality assurance system to provide for confidence between the fuel producers and the fuel users. Biomass resources are potentially the worlds largest renewable energy source – at an annual terrestrial biomass yield of 220 billion oven dry tonnes. Biomass conversion to fuel and chemicals is once again becoming an important alternative to replace oil and coal. Biodiesel from the rape seed oil methylester (RME) produced by farmer cooperatives is about 2000 t RME per year. A large facility of 15000 t RME per year is located at the oil mill at Bruck/Leitha in Austria. RME is excellent substitute for diesel. Already, European countries, mainly France, Italy, Germany and Austria are leading in biodiesel production, nearing 500,000 tons in 1997 out of which 250,000 was produced in France.( Statt, 1998) The production capacity of biodiesel in Germany was fully utilized in1997, the sold quantity amounting to roughly 100,000 t (Groenen,1998). The technologies for producing bio-oil are evolving rapidly with improving process performance , larger yield and better quality products. The challenge is to develop a process technology which can cope with the significant variation in the composition of the raw material. 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. 1.3 BIOFUEL SOURCES Some of the common biomass used are – 12. Fuel wood 13. Cow dung 14. Sawdust 15. Coconut husk 16. Pea nut shell 17. Bagasse of sugarcane 18. Straw 19. Rice hask 20. Culums of pulses 21. Saccharum munja 22. 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.