The total mass of living matter in a given unit area is called biomass. This means that even if plants and animals -- however small or big, had life for a second, they constitute the biomass. It is carbon-based and composed of other molecules of oxygen, nitrogen, and hydrogen. It is a renewable source of energy as the trees and crops can be always grown back. Biomass sources that are currently being used to produce power and heat in large-scale units are solid biomass, biogas, biofuel, and biodiesel.
Plants make their food by the process of photosynthesis. During this process, they trap the sun's energy and convert it into chemical energy. This energy is obtained by animals when they eat various parts of plants. This energy can be obtained and used by human beings to meet their energy requirements. Though the search for renewable energy resources has picked momentum just a couple of decades ago, humans have been using this energy from the beginning of time.
Biomass Energy Conversion
As discussed, biomass is all around us. However, to convert biomass into some energy, so that it can be used for power generation (in industries and even at home for heating and cooking), it has to go through some chemical procedures. There are three ways in which biomass is converted into energy and then used.
In this method, the biomass is heated and not burned, and the matter breaks down into gases, solids, and liquids. With further processing, it is converted into methane and alcohol. The methane that is produced is used as fuel for steam generators.
In this process, enzymes, yeasts, and bacteria are added to the biomass, which starts the process of fermentation and turns into alcohol. Once bacteria react with biomass, methane is produced, which is further used as fuel for power and heat.
Interesting Facts about Biomass Energy
ø In fact, biomass is considered as one of the key renewable resources of the future. It already meets 14% of the world's total energy requirements and 4% of that belongs to the United States alone.
ø Chemically, biomass is made up of complex polymers of carbon, hydrogen, and oxygen. It also contains small amounts of nitrogen and inorganic materials.
ø Although fossil fuels also are formed from ancient biomass, they are not included in biomass, as the carbon atoms that they are made of, have been out of the carbon cycle for long.
ø Almost 10% of the energy consumed in the United States comes from garbage, which is called municipal solid waste (MSW). The biogenic material, like paper, cardboard, food scraps, grass clippings, leaves, leather goods, etc., form the source of biomass energy in MSW. This biomass is used to produce electricity.
ø Like crude oil processing, research is going on to devise ways by which plant biomass can be fractionated in different parts that can then be separately used to produce fuels, chemicals, and other products.
ø Biomass can be used to make energy-rich gas called biogas. Biogas is quite like natural gas that we use in the kitchen.
ø Biomass energy can be used to produce electricity, heat, and steam for the working of refineries.
ø Another useful fact about biomass energy is that it provides an option to put organic waste to good use. This aids in waste management of urban centers.
ø It is an inexhaustible source of energy, as it is derived from living things. However, biomass energy facts, such as it being an expensive process and that burning of ethanol may increase levels of nitrogen dioxide in the atmosphere are certain drawbacks of this form of renewable energy that otherwise has immense potential.
Do fossil fuels add to the carbon dioxide content of the atmosphere?
One of the pros of biomass energy is that it is not considered to contribute to carbon dioxide content of the environment. This is because biomass is formed from carbon dioxide that is absorbed by plants through the process of photosynthesis, which is released into the air once it is burnt. Then why are fossil fuels considered to add to the carbon dioxide content of the atmosphere? Well, that's 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 through biomass take place within a shorter period of time. Due to this, the carbon dioxide content of the environment is less disturbed when biomass is used as compared to burning of fossil fuels.