The Difference of First Generation Biofuels and the Second Generation Biofuels

The first generation biofuels made from sugar, starch, vegetable oil, or animal fats using conventional technology. The ingredients for the production of first generation biofuels are often seeds or grains which are including corn, soybean, and wheat. After fermenting, it produces ethanol which can be mixed with gasoline. Besides, sunflower seeds, which are pressed to yield vegetable oil that can be used in biodiesel.Second-generation biofuel production processes can use a variety of non food crops. These include waste biomass, the stalks of wheat, corn, wood, and special-energy-or-biomass crops.

The advantages of the first generation biofuels are these foods are already available to biofuel through experiment. It can reduce the emission of carbon dioxide during many experiments. However, the first generation biofuels requires the use of food crops such as sugar cane, corn, wheat. These crops are required for food, so if too much biofuel is made from them, food prices could rise and shortages might be experienced in some countries. Corn, wheat and sugar beet also require high agricultural inputs in the form of fertilizers, which limit the greenhouse gas reductions that can be achieved

The goal of second generation biofuel processes is to extend the amount of biofuel that can be produced sustainably by using biomass comprised of the residual non-food parts of current crops, such as them stems, leaves and husks that are left behind once the food crop has been extracted, as well as other crops that are not used for food purposes, such as switch grass, cereals that bear little grain and more fibre, and also industry waste such as wood chips, skins and pulp from fruit pressing etc.

The problem that second generation biofuel processes are addressing is to extract useful feedstocks from this woody or fibrous biomass, where the useful sugars are locked in by lignin and cellulose. All plants contain cellulose and lignin. These are complex carbohydrates (molecules based on sugar). Lignocellulosic ethanol is made by freeing the sugar molecules from cellulose using enzymes, steam heating, or other pre-treatments. These sugars can then be fermented to produce ethanol in the same way as first generation bioethanol production. The by-product of this process is lignin. Lignin can be burned as a carbon neutral fuel to produce heat and power for the processing plant and possibly for surrounding homes and businesses.

written by Maggie

work cited

http://www.biofuelstp.eu/fuelproduction.html#first