What are Biofuels?
Any hydrocarbon fuel that is produced from an organic matter (living or once living material) in a short period of time (days, weeks, or even months) is considered a biofuel.
What are states of their existence?
Biofuels may be solid, liquid or gaseous in nature.
What are the different categories of Biofuels?
There are generally 4 categories of biofuels:
- First generation biofuels: These are made from food sources such as sugar, starch, vegetable oil, or animal fats using conventional technology. Common first-generation biofuels include Bioalcohols, Biodiesel, Vegetable oil, Bioethers, Biogas.
- Second generation biofuels: These are produced from non-food crops or portions of food crops that are not edible and considered as wastes, e.g. stems, husks, wood chips, and fruit skins and peeling. Thermochemical reactions or biochemical conversion process is used for producing such fuels. Examples include cellulose ethanol, biodiesel. Though these fuels do not affect food economy, their production is quite complicated. Also, it is reported that these biofuels emit less greenhouse gases when compared to first generation biofuels.
- Third generation biofuels: These are produced from micro-organisms like algae. Example- Butanol Micro-organisms like algae can be grown using land and water unsuitable for food production, therefore reducing the strain on already depleted water sources.
- Fourth Generation Biofuels: In the production of these fuels, crops that are genetically engineered to take in high amounts of carbon are grown and harvested as biomass. The crops are then converted into fuel using second generation techniques. The fuel is pre-combusted and the carbon is captured. Then the carbon is geo-sequestered, meaning that the carbon is stored in depleted oil or gas fields or in unmineable coal seams. Some of these fuels are considered as carbon negative as their production pulls out carbon from environment.
What are the advantages of Biofuels?
- Availability: biofuels are produced from biomass and thus are renewable.
- Source material: Whereas oil is a limited resource that comes from specific materials, biofuels can be manufactured from a wide range of materials including crop waste, manure, and other byproducts.
- Environment Pollution: Biofuels do not release as much carbon as fossil fuels do but fertilisers that are used in the growing bio fuels lead to greenhouse emissions. Also, biofuels can help in managing the municipal solid wastes i.e. the waste can be converted into fuel.
- Security: Biofuels can be produced locally, which decreases the nation's dependence upon foreign energy. By reducing dependence on foreign fuel sources, countries can protect the integrity of their energy resources and make them safe from outside influences.
- Economic stimulation: Because biofuels are produced locally, biofuel manufacturing plants can employ hundreds or thousands of workers, creating new jobs in rural areas. Biofuel production will also increase the demand for suitable biofuel crops, providing economic stimulation to the agriculture industry.
Are there any disadvantages of Biofuels?
- Efficiency: Fossil Fuels produce more energy than some of the biofuels. E.g. 1 gallon of ethanol produces less energy as compared to 1 gallon of gasoline (a fossil fuel).
- Cost: Pumping fossil fuels from the ground is a difficult and expensive process leading to high costs. Production of biofuels require land, this impacts cost of biofuels as well as that of food crops. Also, though growing engineered biofuel crops can benefit farmers commercially but the excess number of such crops can also lead to loss of biodiversity.
- Food shortages: There is concern that using valuable cropland to grow fuel crops could have an impact on the cost of food and could possibly lead to food shortages.
- Water use: Massive quantities of water are required for proper irrigation of biofuel crops as well as to manufacture the fuel, which could strain local and regional water resources.