Biofuels
First generation biofuels
'First-generation biofuels' are biofuels made from sugar, starch, vegetable oil, or animal fats using conventional technology. The basic feedstocks for the production of first generation biofuels are often seeds or grains such as wheat, which yields starch that is fermented into bioethanol, or sunflower seeds, which are pressed to yield vegetable oil that can be used in biodiesel. These feedstocks could instead enter the animal or human food chain, and as the global population has risen their use in producing biofuels has been criticised for diverting food away from the human food chain, leading to food shortages and price rises.
The most common first generation biofuels are listed below:
Vegetable oil
Biodiesel
Bioalcohol
Biogas
Solid biofuels
Syngas
Second generation biofuels
Supporters of biofuels claim that a more viable solution is to increase political and industrial support for second-generation biofuel implementation from non food crops, including cellulosic biofuels. 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 (e.g. Miscanthus ). Second generation (2G) biofuels use biomass-to-liquid technology, including cellulosic biofuels from non food crops. Many second generation biofuels are under development such as biohydrogen, biomethanol, DMF, Bio-DME, Fischer-Tropsch diesel, biohydrogen diesel, mixed alcohols and wood diesel.
Cellulosic ethanol production uses non food crops or inedible waste products and does not divert food away from the animal or human food chain. Lignocellulose is the "woody" structural material of plants. This feedstock is abundant and diverse, and in some cases (like citrus peels or sawdust) it is a significant disposal problem.
Producing ethanol from cellulose is a difficult technical problem to solve. In nature, ruminant livestock (like cattle ) eat grass and then use slow enzymatic digestive processes to break it into glucose (sugar). In cellulosic ethanol laboratories, various experimental processes are being developed to do the same thing, and then the sugars released can be fermented to make ethanol fuel.
Scientists also work on experimental recombinant DNA genetic engineering organisms that could increase biofuel potential.
Third generation biofuels
Algae fuel, also called oilgae or third generation biofuel, is a biofuel from algae . Algae are low-input, high-yield feedstocks to produce biofuels. It produces 30 times more energy per acre than land. With the higher prices of fossil fuels (petroleum), there is much interest in algaculture (farming algae). One advantage of many biofuels over most other fuel types is that they are biodegradable, and so relatively harmless to the environment if spilled.
The United States Department of Energy estimates that if algae fuel replaced all the petroleum fuel in the United States, it would require 15,000 square miles (38,849 square kilometers ), which is roughly the size of Maryland .
Second and third generation biofuels are also called advanced biofuels.
Algae, such as Chlorella vulgaris, is realtively easy to grow, but the algal oil is hard to extract. There are several approaches, some of which work better than others. See: Prospects for the Biodiesel Industry.
Fourth generation biofuels
An appealing fourth generation biofuel is based on the conversion of vegoil and biodisel into gasoline.
Craig Venter 's company Synthetic Genomics is genetically engineering microorganisms to produce fuel directly from carbon dioxide on an industrial scale.
'First-generation biofuels' are biofuels made from sugar, starch, vegetable oil, or animal fats using conventional technology. The basic feedstocks for the production of first generation biofuels are often seeds or grains such as wheat, which yields starch that is fermented into bioethanol, or sunflower seeds, which are pressed to yield vegetable oil that can be used in biodiesel. These feedstocks could instead enter the animal or human food chain, and as the global population has risen their use in producing biofuels has been criticised for diverting food away from the human food chain, leading to food shortages and price rises.
The most common first generation biofuels are listed below:
Vegetable oil
Biodiesel
Bioalcohol
Biogas
Solid biofuels
Syngas
Second generation biofuels
Supporters of biofuels claim that a more viable solution is to increase political and industrial support for second-generation biofuel implementation from non food crops, including cellulosic biofuels. 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 (e.g. Miscanthus ). Second generation (2G) biofuels use biomass-to-liquid technology, including cellulosic biofuels from non food crops. Many second generation biofuels are under development such as biohydrogen, biomethanol, DMF, Bio-DME, Fischer-Tropsch diesel, biohydrogen diesel, mixed alcohols and wood diesel.
Cellulosic ethanol production uses non food crops or inedible waste products and does not divert food away from the animal or human food chain. Lignocellulose is the "woody" structural material of plants. This feedstock is abundant and diverse, and in some cases (like citrus peels or sawdust) it is a significant disposal problem.
Producing ethanol from cellulose is a difficult technical problem to solve. In nature, ruminant livestock (like cattle ) eat grass and then use slow enzymatic digestive processes to break it into glucose (sugar). In cellulosic ethanol laboratories, various experimental processes are being developed to do the same thing, and then the sugars released can be fermented to make ethanol fuel.
Scientists also work on experimental recombinant DNA genetic engineering organisms that could increase biofuel potential.
Third generation biofuels
Algae fuel, also called oilgae or third generation biofuel, is a biofuel from algae . Algae are low-input, high-yield feedstocks to produce biofuels. It produces 30 times more energy per acre than land. With the higher prices of fossil fuels (petroleum), there is much interest in algaculture (farming algae). One advantage of many biofuels over most other fuel types is that they are biodegradable, and so relatively harmless to the environment if spilled.
The United States Department of Energy estimates that if algae fuel replaced all the petroleum fuel in the United States, it would require 15,000 square miles (38,849 square kilometers ), which is roughly the size of Maryland .
Second and third generation biofuels are also called advanced biofuels.
Algae, such as Chlorella vulgaris, is realtively easy to grow, but the algal oil is hard to extract. There are several approaches, some of which work better than others. See: Prospects for the Biodiesel Industry.
Fourth generation biofuels
An appealing fourth generation biofuel is based on the conversion of vegoil and biodisel into gasoline.
Craig Venter 's company Synthetic Genomics is genetically engineering microorganisms to produce fuel directly from carbon dioxide on an industrial scale.
Biofuels can be defined as a combustible fuel produced from biomass. These fuels are solid, liquid, or gas and derived from recently grown biological material .