Algae are aquatic plants which grow both in fresh waters and oceans. They can prove a cheap and renewable source of energy, as they contain waters and oceans. They can prove a cheap and renewable source of energy, as they contain sufficient lipids, which can be converted into autofuels by a process of chemical conversion. Further. the lipid content of the algae can also increased. Under controlled supply of nitrogen and silicon, algae produce over two-third of its mass as lipids. These lipids are hydrolysed by boiling with hydrochloric acid to yield fatty acids. The latter are then esterified with methyl alcohol by a process called transesterification to produce autofuels like diesel and petrol.
The unicellular algae such as diatoms produce up to 30 times more lipids per unit of growth area than the land plants. They offer an attractive sources of lipids for bio-diesel production. The lipid contents of these algae can also be increased up to 40 to 60 percent (normal being 5 to 10 percent) through recombinant DNA technology involving the transfer of modified ‘ACC gene’ (the gene encoding the enzyme acetyl-COA carbosylase responsible for lipid accumulation) and by manipulating the culture conditions.
A green alga (Botulio yuccas) produces a lipid hydrocarbon called butulio-yussen, approximately 50 percent of its weight. The hydrocarbon butulio-yussen is extracted with the help of hexane or acetone solvent, while the dried alga is being irradiated with supersonic waves.