The organic or waste materials obtained from the plants and animals, is known as biomass. Since plants and animals contain energy, the biomass also contains energy. Plants get energy from the sun by the process of photosynthesis, while the animals eat plants; hence biomass is an important source of energy.
The energy obtained from biomass is called as biomass energy. The biomass energy is type of alternative or renewable energy since the plants and trees will keep on growing and generating the wastes continuously, so this source of energy will be available for unlimited period of time.
The various types of garbage collected in our cities are also a type of biomass. Though the living plants are not considered to be the biomass, the garbage left by them in the form of fallen leaves, dead trees, broken branches of the trees, wasted and leftover crops, chips and pieces of wood etc are all considered to be biomass. The bark and saw dust left from the lumber mills and even the tires and livestock manure can be considered as biomass.
The trash from the house and offices contains some paper products that cannot be recycled back to the other paper products but they can also be used as the biomass. Recycling such wastes for producing biomass fuel would reduce pressure on our landfills. It is unbelievable that all these materials that create lots of disposal problems can be used to generate energy that too in the form of electricity.
In US, California itself produces almost 60 million bone dry tons of biomass every year, of which almost five million tons is used to produce biomass energy in the form of electricity. The biomass collected in California comprises of lumber mills wastes, wooden waste collected from urban areas, residues from the agricultural lands and forests, and other livestock.
The wastes generated by the humans and animals like cows are also types of biomass. By using this type of biomass for producing energy it becomes easier to manage and control the landfills.

Biomass used as the Source of Energy
All the types of biomass contain one or the types of plants and animals wastes. When the biomass obtained from plants it is burnt it catches fire instantly or after some time and releases a lot of heat. During burning the chemical energy stored within the biomass is converted into heat energy. The heat produced during the burning of biomass can be used for a number of applications like heating water, heating the rooms, producing steam, cooking the food, and for other domestic and industrial applications.
Some decomposing garbage, and wastes from humans and animals can also be used as biomass to produce methane gas, which can be used directly as the fuel. Methane is an important part of natural gas, which is used extensively as a cooking gas and also for running a number of vehicles like cars and trucks. The methane gas obtained by this method is also called as the landfill gas or biogas.

The Fuels Obtained from Biomass
Besides using the biomass for producing heat, it can also be used to produce fuels. The fuels produced from the biomass are called as biofuels. The biofuels can be used independently to or in combination with the other fuels like gasoline and diesel. Some of the popular biofuels made from the biomass are ethanol, biodiesel and natural gas.
Ethanol is produced by fermentation of sugar which can be found in sugarcane, grains like corn, sorghum and wheat, and other sources like potato skins, rice, sugar beets and yard clippings. The biodiesel can be produced from vegetable oil and animal fat feedstock. In this age of escalating fuel prices, biodiesel is one of the most popular types of alternative fuel for the vehicles. Biodiesel is mixed with traditional diesel in certain proportions to power the vehicles. The biodiesel is a clean fuel and does not produce any pollution. The natural gas can be obtained from the biomass like cow dung, human wastes, and livestock wastes. Methane, which is important part of the natural gas, is produced from the biomass.

Benefits of Using the Biomass Energy
Here are some of the important benefits of biomass energy:
1) Biomass energy is obtained mainly from the plants, animals, human wastes and garbage which would have otherwise created dirty environment and lots of disposal problems. When converted to biomass energy most of the wastes get burnt completely or they get converted to useful manure. Thus using biomass energy helps keeping our surroundings clean.
2) Biomass is a renewable source of energy that would last as long as there is plant, animal, and human life on the earth.
3) Biomass helps producing indigenous fuels and helps reducing dependency for fuels on other countries. 
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