The utilization of organic operators to change over moderately diffuse and badly designed to utilize wellsprings of vitality, e.g., biomass and daylight, into more vitality thick and helpful to utilize energizes, eg. methane, ethanol, butanol, bio-diesel and hydrogen, constitutes fuel biotechnology. Biomass is the aggregate cell dry weight or natural material created by a living being generally from carbon dioxide and daylight, while organically delivered powers are typically called as the bio fuels.
However, the ultimate source of energy for both petroleum derived fuels and bio fuels is sun, and both of them are derived from biomass. Biomass still contributes a large part 74% of the energy needs of developing countries, while only about 2 % of energy used by developed countries is directly obtained from biomass.
USEFUL FEATURES OF BIO-FUELS
- Most of the bio fuels are derived from biomass, which is renewable, low cost and locally available entailing little or no commitment of foreign exchange.
- In general, they lead to relatively low carbon dioxide omission than fossil fuels.
- They do not contribute to environmental pollution due to gases like SO2 etc.
- The substrate is often a waste, including municipal waste. Use of such materials for bio fuel production not only generates a more valuable product from low cost substrate but also help in cleaning up the environment.
AREAS FOR FUTURE RESEARCH FOCUS
- More efficient processes especially continuous processes must be developed to reduce the production cost.
- To achieve the above, organisms with higher product yields, and greater product tolerance must be developed.
- Efficient processes to utilize low cost substrates for bio fuel production are urgently needed.
- The continuous processes of bio fuel production cannot allow for continuous selection programmes to maintain the desirable features of microbes. In any case, such selection programmes add to the production cost. Therefore, it is important to develop genetically stable high producing micro-organisms.
- The sources of biomass or their derivatives to be used as substrates should be identified and their cheap and abundant supply should be ensured. The biomass may be obtained from fast growing or high producing plant species, called energy crops, suited for this purpose. Genetic and agronomic improvements of such crops would reduce bio fuel production costs.
Diesel like liquid obtained from materials of biological origin is called biodiesel. Biodiesel can be obtained either from lipids accumulated in plants and algae or from hydrocarbons produced by some plants and algae.
Biogas is the mixture of gases produced by anaerobic bacterial digestion of organic matter. Biogas consists mainly of methane and carbon dioxide, plus traces of hydrogen and several other gases. It is obtained by anaerobic degradation of variety of organic materials, ranging from simple sugars to polymers like cellulose and nucleic acids by a community of organisms.
Ethanol produced by microorganisms, e.g., Saccharomyces cerevisiae, from biomass is called bio ethanol. Bio ethanol is most widely used bio fuel for transport purposes, especially in Brazil and USA. The interest in use of bio ethanol as petrol replacement began in Brazil and USA during 1980s.