In the world of energy production, biomass is one of the common ways energy is produced using animal waste, wood pellets, etc. to create electricity. Even though there might be some environmental factors, biomass energy is called a renewable energy source. Debate is still ongoing on whether biomass is the greenest type of energy compared to others.
Over the years, biomass energy seems to be beneficial and serves as an alternative energy source with much potential to be both reliable and consistent. In the UK today, over 45% of renewable energy consumed, biomass energy provides about 12% which is quite much. That makes it the second-largest contributor after wind. Today you’ll get to know the definition, applications, types, working, environmental effect, advantages, and disadvantages of biomass energy. you’ll also get to know how biomass is converted into energy, and how it’s used to generate electricity.
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What is biomass energy?
Biomass simply means ‘Organic matter’. That is, biomass is anything that’s alive or been alive such as animal waste, crop waste, garden waste, etc. so, biomass renewable energy is the power obtained from the method of using biomass matter. Biomass obtains and stored energy from the sun, plants absorb the sun’s energy in a process called photosynthesis. The chemical energy in plants gets passed on to animals and people eat them.
The plant and animal material can also be sugarcane, corn crops, wood chips, or even dung. These materials are called feedstocks when used as biomass.
According to the EU and UN, biomass is a renewable source of energy because it can be renewed by planting more trees and plants. However, it might not be as green as one may hope because burning biomass creates a carbon debt, which could take up to 104 years to reabsorb. But it is still considered a renewable source because of the following:
- Waste residues from forest resources, mills, and scrap wood will never cease to exist.
- Forests are properly managed due to their benefits.
Biomass sources for energy include:
- Wood and wood processing wastes – firewood, wood pellets, and wood chips, lumber and furniture mill sawdust and waste, and black liquor from pulp and paper mills
- Agricultural crops and waste materials – corn, soybeans, sugar cane, switchgrass, woody plants, and algae, and crop and food processing residues
- Biogenic materials in municipal solid waste – paper, cotton, and wool products, and food, yard, and wood wastes
- Animal manure and human sewage
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Applications of biomass energy
The applications of biomass energy so vast but biomass feedstocks can be used to create 3 types of energy; heat, electricity, and biofuels, such as biodiesel. Most biomass plants are multi-taskers as they create both heat and electricity. These plants are often called CHP (Combined Heat and Power) plants. They create heat by just burning the feedstocks just as it is done thousands of years.
Applications of biomass energy can vary from small stoves used in homes to large power plants used by centralized utilities for the production of electricity. In residential applications, biomass is used mostly for cooking and heating. Wood is the most common resource of fuel, although other materials can be utilized. Woodstoves of new designs can improve the efficiency of cooling or heating system, decreasing the amount of fuel that is required.
In industry and businesses, the use of biomass energy includes space heating, hot water heating, and electricity generation. Most industrial facilities such as lumber mills, naturally produce organic waste.
In 2020, biomass energy offers about 4,532 trillion British thermal units (TBtu) or about 4.5 quadrillion (Btu) which is about 4.9% of total U.S. primary energy consumption. About 2,101 TBtu were from wood and wood-derived biomass, 2,000 TBtu were from biofuels (mainly ethanol), and 430 TBtu were from the biomass in municipal wastes.
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Types of biomass energy resources
Below are the various types of biomass energy sources:
Wood and wood waste
These are the most common form of biomass energy sources. It has been used for thousands of years by burning wood for heating and cooking. Biomass continues to be a major source of energy today, about 84 percent of wood and wood waste fuel used in the United States is consumed by the industry, commercial businesses, and electric power producers. The rest, mainly wood, is used in homes for heating and cooking.
Most common wood wastes include bark, sawdust, wood chips, and wood scrap. They provide only about 2 percent of the energy used today. Many wood and paper manufacturing industries, use wood waste to produce their own steam and electricity. This saves more money for the company and they don’t have to dispose of waste, as well as by as much electricity.
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Municipal solid waste, landfill gas, & biogas
Municipal solid waste (MSW) is garbage or trash such as food scraps, lawn clippings, and leaves. MSW can be a source of energy either by burning MSW in waste-to-energy plants or by capturing biomass. In the first one, the trash is burned to produce steam that is used for either heating or generating electricity.
in landfills, biomass rots and releases methane gas, which is also called biogas or landfill gas. Most landfills have a system of collecting methane gas which is used as a fuel source. Some dairy farmers obtain biogas from tanks called ‘digesters’ where they put all of the muck and manure from their barns.
There are two common biofuels which include ethanol and biodiesel. These fuels are made from biomass materials, usually blended with petroleum fuels such as gasoline and diesel fuel. Although they can be used on their own. However, using ethanol or biodiesel eliminates much burning of fossil fuel. These biofuels are usually more expensive than fossil fuels but they are cleaner-burning fuels, producing lesser air pollutants.
Ethanol is an alcohol fuel made from sugar found in grains like corn, sorghum, and wheat as well as potato skins, rice, sugar cane, sugar beets, and yard clipping. Research is still ongoing on how to make ethanol cheaper by using all parts of plants and trees. On the other hand, biodiesel is a fuel made with vegetable oils, fats, or greases such as recycled restaurant grease. It is used in diesel engines without changing them. biodiesel is a renewable fuel, is safe, biodegradable, and reduces the emission of most air pollutants.
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Environmental effect of biomass
Biomass can pollute the air when burned, although not as fossil fuels. Biomass fuels do not produce pollutants like sulfur when burned but it does release carbon dioxide, a greenhouse gas. However, when biomass crops are grown, a nearly equivalent amount of carbon dioxide is captured through photosynthesis. The different types of biomass resources and uses impact the environment in different ways. For example, the smoke from burning wood contains pollutants like carbon monoxide and particulate matter, most areas of the country won’t allow the use of wood-burning fireplaces or stoves on high pollution days. Also, collecting and using landfills and biogas reduces the amount of methane that is released into the air. Methane is one of the greenhouse gases associated the global climate change.
How biomass is converted to energy
Converting biomass to energy can take place through various processes such as:
- Direct combustion (burning) to produce heat.
- Thermochemical conversion to produce solid, gaseous, and liquid fuels.
- Chemical conversion to produce liquid fuels.
- Biological conversion to produce liquid and gaseous fuels.
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Direct combustion is the most common form of converting biomass into useful energy. biomass can be burned directly for heating buildings and water, for industrial processes, and for generating electricity in steam turbines. In a chemical conversion process known as transesterification, it is used for converting vegetable oils, animal fats, and greases into fatty acid methyl esters. It is used to produce biodiesel.
The biological conversion includes the fermentation to convert biomass into ethanol and anaerobic digestion to produce renewable natural gas. This renewable natural gas is also called biogas or biomethane.
When biomass is burnt, it releases energy in form of heat which is used to generate steam. The energy from the steam is directed through pipes to run turbines. The steam rises up to run turbines that eventually produce electricity or generate heat for homes and industries.
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Watch the video below to learn more on how biomass is converted into energy:
Advantages and disadvantages of biomass energy resources
Below are the benefits of biomass energy in their various applications.
- Biomass is a clean source of energy.
- It is good for mother nature and business.
- Biomass emits carbon dioxide and captures it back for its own growth.
- Minimizes the possibility of fill-up of landfills
- Harmful wastes are converted into useful energy.
- The emission of biomass resources is not harmful.
- Biomass energy is totally natural and doesn’t present any side effects when used.
- Biomass resources life cycle is complete.
- They are renewable resources.
- Biomass energy dials back on fossil fuel dependence.
- Biomass resources can be used to develop diverse products.
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Despite to good benefits of biomass energy resources, some limitations still occur. Below are the disadvantages of biomass energy in its various applications.
- Biodiesel such as ethanol is comparatively inefficient to fossil fuel.
- They are sometimes mixed with fossil fuel to perform better.
- Combustion of biomass requires lots of space.
- Gasses such as methane are emitted into the environment when biomass resources are burned.
- Using biomass energy results in environmental degradation.
- It may be harmful to mother nature.
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According to the EU and UN, biomass is a renewable source of energy because it can be renewed by planting more trees and plants. biomass renewable energy is the power obtained from the method of using biomass matter. Biomass feedstocks can be used to create 3 types of energy; heat, electricity, and biofuels, such as biodiesel. That is all for this article, where the definition, applications, types, working, advantages and disadvantages of biomass energy. you also learned how biomass is converted into energy, and how it’s used to generate electricity.
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