Biomass Energy Overview

The confusion about the benefits and hazards of biomass energy is still haunting the human mind. Many are unable to decide whether to use it or to abandon it. I have tried to portray a picture of the biomass power generation system and left the decision to the reader. Now it is up to you that how useful you evaluate this

technique.

  How biomass Energy Works ?

When biological material extracted from some living being is used as a renewable source of energy it is called Biomass. It is usually comprised of the flora grown to produce electricity or heat - mostly remains of forest such as dead trees or part of trees. The biomass is transformed into chemicals so it can be used to generate required energy. 3.3 per cent of United States energy comes from biomass. The biomass station works just like the fossil fuel power station. It does not include fossil fuels as they are transformed into coal, gas, petroleum by geological procedures. Fossils contain that carbon dioxide which was long abandoned in the carbon cycle and is no more considered as a part of the system.  

Plants and trees are the best mean to absorb the carbon dioxide in atmosphere. When plants are burnt to gain energy or heat then the process of combustion adds carbon dioxide into the environment. If the plants used as a source of energy are grown again than the method is carbon neutral – as the next generation of plants dilute the concentration of carbon dioxide in atmosphere. Following are the material which can be used as biomass: woodchips, wood (like poplar, willow, eucalyptus, etc.), paper, trash, agricultural crops (like sugar cane. corn), dung, animal waste, sewage, algae, sewage, etc.  

Wood has remained one of the most famous and abundantly utilized sources of heat. It is used to cook food and to warm homes. The significance of wood as the source of energy is now declining although it still provides a small percentage of energy. Fermentation of sugar cane produces alcohol which put forth energy on burning. Moreover, the cane itself and its pulp (the residue after juice extraction) can be burned to run generators. The energy produced by the biomass of sugar canes can not only use in running the mill but also to provide electricity to adjacent areas. Bio-fuels (biogas, bio-butanol, bio-ethanol, bio-diesel, etc.) can be made by bio-conversing the waste of animals and plants.  

Source for biomass  : 

Biomass energy is usually taken from three sources wood, biological wastes and alcohol fuels. Wood is used either directly or by using its waste products such as pulp that comes out as a waste product from the paper industry. The other use is that of the waste. It mainly is derived from landfills and other waste from the industry. Perhaps the best sources are concentrated waste materials. Forests are very important source of biomass for they contain a wide variety of wood that can be used in the timber processing plants.

In the field of agriculture different crops, when harvested can be of great use regarding the biomass collection and a later use. For example upon harvest of cotton, peanuts, rice sugar cane, a large amount of waste material is left behind. These items that include animal and plant manure, and crop wastes can be used as fuel.

In cities there are concentrated biomass sources such as sewage, landfills, food and dairy industries that can be used. While quickly growing crops like switch grass and cotton wood tree can also be used as fuels. So an increase in plantation would increase in our biomass sources and on the other hand would be more economic 

 

 

Biomass conversion to other useful forms of energy : 

The more common methods of transferring the biomass to other forms of energy and resources are the thermal and biochemical. The thermal conversion requires heat to convert the biomass into other compounds. The specific conditions of pressure, heat and chemicals convert same biomass to different products. The other method of conversion is natural and uses the organic nature of the biomass in this context. Biodegraders and microbes use the components in the biomass and convert them into other forms of chemicals. In this way biodiesel and other fuels can be generated provided the necessary conditions are fulfilled. Currently biomass is widely used to generate electricity. In this process the biomass is burnt and used to heat water, which produces steam. This steam is used in various steps to generate turbines and their electricity generators to produce electricity. The other important use of biomass is in the production of biogas. Biogas is energy rich and is produced when the biomass rots in the absence of air. This biogas is generated by the action of different microbes that are nature free factories of chemical conversion. The other use is waste-to-energy conversion of the biomass. The solid waste that is usually disposed off in landfills is usually converted into liquid or gaseous fuels. This is more likely to be a better way because if not used this way the solid waste would be disposed into landfills any way, so using solid waste as an energy source is a cheaper and economic way of energy production.  

In different parts of the world, especially in China, farmers put their garbage and manure in large tanks void of air. The biomass is then converted into biogas which in turn is used for cooking food and lighting their homes. Keeping in mind the environmental hazards related to the use of gasoline there is an expensive yet environmental friendly use of alcohol, ethanol. Corn and wheat are the sources for alcohol production through fermentation. Sometimes ethanol and gasoline are mixed together so as to make it more environment friendly and less expensive. The industrial use of biomass is in the field of fermentation where the crops can be fermented to give ethanol fuels, that burn smoothly and are environmental friendly. This requires special crop production for the soul purpose of ethanol production. The other way of ethanol production is the usage of wood but that is not very efficient because of lack of effective methods and technology available.

 

Environmental Impacts : 

On combustion the biomass generate air emissions. These emissions depend upon the type of biomass fuel and the technology used. Mostly various gases like CO2, SO2 and NOx (Nitrogen oxides) are emitted. The major part of the wood, approximately 50% is carbon based. Sulfur is present in very small quantities. The nitrogen gases are emitted in varied amounts depending upon the techniques of biomass usage, but in general the level nitrogen gases released from biomass emission is greater than the coal or other hydrocarbon fuels which seeks better processes to control its emission. Wood is mostly taken from forests and so needs very strict observation regarding its treatment as biomass, because once wood from forest is removed with non-constructive forestry techniques, the renewal of the lost wood could take a very long time for reforestation, thus causing imbalance in nature’s normal levels of carbon. The carbon thus released is not fixed back and therefore creates higher levels of carbon dioxide in the atmosphere leading to various environmental problems, most important of which is the global warming. On the other hand plant manure and wastes of agriculture are a good renewable biomass source and thus can be a more appreciated choice where the carbon source is renewed again by simply more plantation.  

One important advantage of biomass usage is the lesser emissions of carcinogenic elements in the environment, unlike the hydrocarbons and fossil fuels.  

But the biomass has its hazards too. For example in waste-to-energy conversion of biomass there is a possibility of toxic heavy metal release like mercury and cadmium into the atmosphere. But using efficient technique and machines in the process may lower down the risk of heavy metal release.

If we use biomass in a proper and controlled way, keeping in mind the hazards and problems related to the environment and use better and more precise methods then the renewable biomass would certainly be a better option than the potentially hazardous hydrocarbon energy sources.

Advantages of Biomass Energy : 

The best thing about this technique is the utilization of wastage to create energy but the process has its limitations. I will give you a picture of both. The biomass energy is quite profitable. Let us review some of its advantages:

• The biomass is abundant in nature and is a renewable source of energy.
  
• Source of energy is very cheap.
  
• The best part of this procedure is the utilization of waste of multi types.
• The level of air pollutants (like carbon mono oxide and ethanol) can be controlled and reduced by Ethanol. The biomass absorbs carbon dioxide during its growth so on the whole there is no addition in the quantity of green house gas.
• Biomass can not only produce electricity but also heat for the homes.
• Biomass decreases the reliance on fuels like oil and petroleum.

Disadvantages of Biomass Energy  : 

However there are disadvantages of the biomass. Some of them are as follows:  

• Although the net addition of carbon dioxide is zero but the burning of biomass is a polluted procedure.
• The plan may not be effective in terms of cost. Like fossil fuels the product is not ready to use. The processing of biomass is comparatively expensive.
• Hazardous chemicals like sulphar dioxide and nitrogen dioxide are produced as a result of biomass burning.
• It is not environment friendly method as the number of trees cut down affects the ecological balance. Animals lose protection and natural habitant as a result of cutting trees.
• Large lands are required to grow enough amount of biomass that are necessary for producing bio-fuels.
• The growth and collection of fuel on such massive level is also very tough.