1 B IOENERGY

Bioenergy is energy contained in living or recently living biological organisms, a definition which specifically excludes fossil fuels. Plants get bioenergy through photosynthesis, and animals get it by consuming plants. Organic material containing bioenergy is known as biomass. Humans can use this biomass in many different ways, through something as simple as burning wood for heat, or as complex as genetically modifying bacteria to create cellulosic ethanol. Since almost all bioenergy can be traced back to energy from sunlight, bioenergy has the major advantage of being a renewable energy source. However, it is important that bioenergy be harnessed in a sustainable fashion. A specific plant or substance used for bioenergy is called a feedstock. Feedstocks are usually converted into a more easily usable form, usually a liquid fuel. Types of Bioenergy Liquid biofuels Liquid biofuels have attracted much attention and investment because they can be used to replace or supplement traditional petroleum-based transportation fuels and can be used in existing vehicles with little or no modification to engines and fueling systems. They can also be used for heating and electricity production. Large quantities of liquid biofuels are presently used in many countries, and the potential exists to greatly expand their use in the future. The two most common kinds of liquid biofuels are ethanol and biodiesel, but a range of other liquid fuels exist or are being developed. Solid biofuels Solid biofuels include wood, manure or charcoal burned as fuel as well as more recent innovations like high-density clean burning pellets. Solid biomass can be burned for heat or to produce electricity either by itself or as part of a co-firing power plant.

Biofuel
DEFINITION Biofuels is a collective term for liquid fuels derived from renewable sources, including ethanol, biodiesel, and other renewable liquid fuels. i. biofuels are liquid or gaseous fuels produced from biomass resources and used in place of, or in addition to, diesel, petrol or other fossil fuels for transport, stationary, portable and other applications; ii. biomass resources are the biodegradable fraction of products, wastes and residues from agriculture, forestry and related industries as well as the biodegradable fraction of industrial and municipal wastes. 3.2 The scope of the Policy encompasses bio-ethanol, bio-diesel and other biofuels, as listed below:-i. bio -ethanol: ethanol produced from biomass such as sugar containing materials, like sugar cane, sugar beet, sweet sorghum, etc.; starch containing materials such as corn, cassava, algae etc.; and, cellulosic materials such as bagasse, wood waste, agricultural and forestry residues etc. ; ii. biodiesel: a methyl or ethyl ester of fatty acids produced from vegetable oils, both edible and non-edible, or animal fat of diesel quality; and , iii. other biofuels: biomethanol, biosynthetic fuels etc.

TYPE OF BIO FUEL

1. 2. 3. 4. 5.

Bioethanol Lipid derived biofuels Biomass-to-liquid(BtL) fuel Bio methane Bio hydrogen

Pathway of different bio fuels

2 B IOETHANOL
Ethanol, also known as ethyl alcohol or grade alcohol, is a flammable, colorless chemical compound, one of the alcohols that is most often found in alcoholic beverages. Its molecular formula is C2H6 O, Bio ethanol can be produced from any biological feedstock that contains appreciable amounts of sugar or material that can be converted into sugar such as starch or cellulose. Two example of feedstock for ethanol production are sugar beets and sugar cane which contain high percentages of sugar. Sugar can be easily fermented. For example, Brazil developed a successful fuel ethanol program from sugarcane. In Europe, sugar beets are used for ethanol production. Corn, wheat, barley, rye and other cereals are typical feedstocks containing starch in their kernels. Starch can relatively easily be converted into sugar and then into ethanol. Other starchy crops that can be used for bioethanol production are sorghum grains, cassava and potatoes. Advantage of bio ethanol is that its octane number is higher than the octane number of conventional fuel. When stored as a pure fuel it has a low vapor pressure than gasoline, and has less evaporative emissions. The major part of engine exhaust steams during ethanol combustion consists of the component nitrogen, carbon dioxide and water. All three components are non-toxic to human health.

3 L IPID DERIVED BIOFUELS

A large portion of biofuels can be received from lipid sources. There exist mainly two types of fuels that are based on lipids: pure plant oil' (PPO) and biodiesel. Due to similar primary process steps of PPO and biodiesel, they are together under the title "lipid derived fuels". For example, feedstock production and oil extraction are the same process steps for both fuels. But, for the final production of PPO some additional purification steps are necessary, whereas for biodiesel the transesterification step has to be applied. Nevertheless, both end products (PPO and biodiesel) are completely different in properties.

4 B IOMASS-TO-LIQUID(BTL) FUEL

5 B IO METHANE

6 B IO HYDROGEN

S OME FACTS ABOUT BIO FUEL

Biomass includes varied organic matter like grass, leaves, wood, wood chips, rice husk, peanut shells, sugarcane fiber, sewage etc. Biomass energy is renewable form energy because plants can be grown in a short time. So it is considered one of the key renewable resources of the future. Did you know it already meets 14% of the world's total energy requirements and 4% of 14% of the energy is the United States alone. Scientists are trying to find more efficient ways of using biomass energy so it has greater benefits for the environment than fossilized fuels. Biomass energy will help the world cut down on waste production and emission of greenhouse gasses. Biomass is made of complex polymers of carbon, hydrogen and oxygen. It also contains small amounts of nitrogen and inorganic materials. Although fossil fuels also are formed from ancient biomass, they are not included in biomass as the carbon atoms that they are made of, because it have been out of the carbon cycle for long. One of the biomass energy pros is that it is not considered to contribute to carbon dioxide content of the environment. It is so because biomass is formed from carbon dioxide that is absorbed by plants though the process of photosynthesis which is released back into the air once it is burnt. But then why are fossil fuels considered to add to carbon dioxide content of the atmosphere? It is because while fossil fuels are releasing carbon-dioxide into

the atmosphere that was removed thousands of years ago, the removal and addition of carbon dioxide though biomass takes place within a shorter period of time. Due to this the carbon dioxide content of the environment is less disturbed when biomass is used than when burning fossil fuels. One of the oldest ways of extracting biomass energy is by burning the sources to get heat. The other non combustible methods are through thermal, chemical and biochemical methods. About 10% of the biomass energy used by United States comes from garbage. This biomass is used to produce electricity.Biomass can be used to make energy-rich gas called biogas. Biogas is like the gas that we use in most kitchens.

R EFERENCE
1. http://bioenergy.ucdavis.edu 2. Biofuel technology handbook 2007 by Dominik Rutz &Rainer Janssen. 3. National policy on biofuel : government of India ministry of new and renewable energy 4. Biofuels Issues and Trends October 2012: U.S. Department of Energy