Biofuel is defined as solid, liquid or gaseous fuel obtained from relatively recently lifeless biological material and is different from fossil fuels, which are derived from long dead biological material. Also, various plants and plant-derived materials are used for biofuel manufacturing.

Globally, biofuels are most commonly used to power vehicles, heat homes, and for cooking. Biofuel industries are expanding in Europe, Asia and the Americas. Recent technology developed at Los Alamos National Lab even allows for the conversion of pollution into renewable bio fuel. Agrofuels are biofuels which are produced from specific crops, rather than from waste processes such as landfill off-gassing or recycled vegetable oil.

There are two common strategies of producing liquid and gaseous agrofuels. One is to grow crops high in sugar (sugar cane, sugar beet, and sweet sorghum) or starch (corn/maize), and then use yeast fermentation to produce ethyl alcohol (ethanol). The second is to grow plants that contain high amounts of vegetable oil, such as oil palm, soybean, algae, jatropha, or pongamia pinnata. When these oils are heated, their viscosity is reduced, and they can be burned directly in a diesel engine, or they can be chemically processed to produce fuels such as biodiesel. Wood and its byproducts can also be converted into biofuels such as woodgas, methanol or ethanol fuel . It is also possible to make cellulosic ethanol from non-edible plant parts, but this can be difficult to accomplish economically..

Biomass

Biomass is made from many types of waste organic matter (both animal and vegetable) such as crop stalks, tree thinning, wooden pallets, construction waste, chicken and pig waste, agricultural waste and lawn trimmings.

It is used to produce power, heat & steam and fuel, through a number of different processes. Although renewable, biomass often involves a burning process that produces emissions such as Sulphur Dioxide (SO₂), Nitrogen Oxides (NO_x) and Carbon Dioxide (CO₂), but fortunately in quantities far less than those emitted by coal plants. However, proponents of coal plants feel that their way of doing it is a lot cheaper and there is a lot of dispute over this.

Biomass is one of the few forms of energy that can be used in a carbon negative mannerFact: date=March 2009. When biomass is combusted to produce heat, it releases less carbon than was absorbed by the plant material during the plant's lifecycleFact: date=March 2009. This is because (1) approximately one third of the carbon absorbed by the plant during its life is sequestered in its rootsFact: date=March 2009, which are left in the soil to rot and fertilize nearby plant life, and (2) combustion of biomass produces 1-10% solid ashFact: date=March 2009 (depending on type of plant used), which is extremely high in carbon (this ash is commonly used as fertilizer).