What is Biomass in Ecology? Use of Energy in Biomass as Biofuel

What is Biomass?

Biomass in ecology is renewable organic material from living organisms, such as plants and animals. These organic materials can be used as fuel to produce heat or electricity. Hence, in the context of energy production, biomass can be referred to as animal and plant material used as fuel to produce heat or electricity.

However, some can be used directly as fuel, such as wood logs. Hence, biofuel and biomass are used interchangeably, by some people. Waste, plants, and wood are the common organic material used for energy. These organic materials are usually called biomass feedstocks.

Biomass has stored chemical energy that is first derived from the sun as in the case of plants through photosynthesis. However, the energy gotten from these organisms can be converted directly or indirectly into usable energy. Directly,  biomass can be burned to produce heat or converted into electricity. Indirectly, it can be processed into biofuel.

Biomass provided nearly 5 quadrillion British thermal units (Btu) in 2020. Also, in the same year, it provided about 5% of the total main energy use in the United States. It happens to be an important fuel especially for heating and cooking in developing countries. Bioenergy use for electricity generation and transportation is increasing in many developed countries. The usage of biomass is seen to be a means of avoiding the emission of carbon dioxide from the use of fossil fuels.

Since biomass can be made anywhere that animals or plants live, every area has its own locally generated biomass feedstocks. These feedstocks could either be from the forest, agriculture, and urban sources. Hence there is a wide variety of biomass feedstocks available. More so, biomass is a widespread and flexible resource as it can be converted into liquid fuels, electric power, heat, or biobased products to meet local needs.

Pyramid of Biomass

A pyramid of biomass portrays the flow of energy between various trophic levels in ecology. Hence a biomass pyramid indicates the relationship between the trophic level and biomass by quantifying the biomass present at each trophic level.

A biomass pyramid is a graphical representation of the total amount of living or organic matter in an ecosystem present in a unit area at different trophic levels. Biomass quantification uses grams per square meter to show the volume of organic matter that can be found in an ecosystem at a given time.

Producers like plants and consumers like animals make up the pyramid of biomass which shows all their comparative masses at the same time. The biomass pyramid may be inverted. In a pond ecosystem, for instance, the standing crop of phytoplankton (major producers) will be lower than the mass of the heterotrophs (fish and insects) at any given time.

Biomass examples

• Human sewage and animal manure
• Wood: such as firewood
• Wood processing wastes: such as lumber, wood chips, furniture mill sawdust, paper mills, black liquor from pulp
• Agricultural crops
• Food processing residues
• Algae
• Biogenic materials in municipal solid waste: such as cotton, wool, paper, food, wood wastes

Types of Biomass

• Agricultural crop residue
• Dedicated energy crops
• Forestry residues
• Algae
• Municipal waste
• Wet waste
• Wood processing residues
• Purpose-grown grasses
• Industrial waste
• Wood energy crops
• Food waste
• Urban wood waste

Biomass feedstocks are those organic materials that make up the biomass. Such biomass includes the plants, materials, and waste listed and discussed below:

• Agricultural crop residue

Agricultural crop residues include the leaves and stalks of agricultural crops. They are abundant and widely distributed across the world. Common examples are:

• Corn stover (leaves, cobs, husks, and stalks)
• Oat straw,
• Wheat straw
• Barley straw
• Rice straw
• sorghum stubble

Selling some of these residues to a local biorefinery should be encouraged as it gives an opportunity for farmers to make extra income.

• Dedicated energy crops

Dedicated energy crops are non-food crops. They can be grown on marginal land specifically to provide biomass. There are 2 types of dedicated energy crops.

1. Herbaceous energy crop: These crops are perennial,  that is, they live for more than two years. Hence, these grasses are harvested annually after taking 2-3 years to attain full productivity. Such grasses include bamboo, switchgrass, sweet sorghum, Kochia, tall fescue, miscanthus, wheatgrass, and many others.
2. Woody energy crops: These short-rotation woody crops are fast-growing trees. They are harvested within 5-8 years after planting. Such crops include hybrid poplar, silver maple, green ash, sweetgum, sycamore, hybrid willow, black walnut, and eastern cottonwood.

• Forestry residues

Forest biomass feedstocks are of two categories:

1. The whole tree is harvested basically for biomass.
2. Forest residues that are left after logging timber. Forest residues such as tops, limbs, culled trees, and tree components that would be otherwise unmerchantable are left after logging and timber harvest.

After timber harvest, diseased, dead, poorly formed, or other unmerchantable trees are often left in the woods. Some of these wood residues and debris can be collected for bioenergy use. Also, some can be left behind to maintain proper nutrient and hydrologic features in the habitat.

• Algae

Algae are feedstocks too. The algae for bioenergy are a diverse group of highly productive organisms which include macroalgae (seaweed), microalgae, and cyanobacteria. Many of them use sunlight and nutrients to create biomass. The biomass contains essential components like proteins, lipids, and carbohydrates. These can be converted and upgraded to a variety of products and biofuels.

Furthermore, algae can grow by using saline, fresh, or brackish water got from groundwater, surface water sources, or seawater. Also, they can grow in water from produced water generated from oil and gas drilling operations, treated industrial wastewater, or municipal, agricultural, and aquaculture wastewater.

• Sorted municipal solid waste

Sorted municipal solid waste resources include mixed residential and commercial garbage. Such waste includes plastics, leather, rubber, food wastes, textiles, yard trimmings, paper, and paperboard. Using sorted municipal solid waste for bioenergy also creates an opportunity to reduce commercial and residential waste. This can be done by diverting significant volumes of these wastes from landfills to the refinery.

• Wood processing residue

Wood processing yields wood processing residues which are made up of waste streams and byproducts. These residues have energy potential. For instance, the unused sawdust, barks, leaves, and branches that are produce during the processing of wood for pulp or products can be converted into bioproducts or biofuel. These residues can be convenient and inexpensive sources of bioenergy.

• Wet waste

Wet waste feedstocks include institutional, commercial, and residential food wastes. Also included are manure slurries from concentrated livestock operations, organic-rich biosolids, organic wastes from industrial operations, and biogas that are derived from any of the above feedstock streams. Converting these waste streams into energy will help solve waste-disposal problems and create additional revenue for rural economies.

Is Biomass renewable?

Yes, it is renewable. Biomass grown through sustainable means is said to be a renewable source of energy. This is because of its growth process and energy that comes from the sun. Through a process of photosynthesis, plants absorb energy from the sun. In this process, plants convert the water from the ground and carbon dioxide in the atmosphere into carbohydrates. Since biomass comes from living matter, it grows naturally.

Therefore, the carbon dioxide released when biomass is combusted as a source of energy either for electricity production or heat, balances the effect of the amount of carbon dioxide absorbed from the atmosphere while it was growing. This simply means when biomass (plants or animals) is burned, they turn back to carbon dioxide and water. Hence releasing the sun’s energy that was initially utilized. So, bioenergy is a renewable energy source because more plants and crop waste will always exist and as long as they exist, this source of energy will last.

Biomass Energy (Bioenergy)

Every living plant and animal matter has some form of energy stored in the form of carbohydrates. The waste products these organisms leave in the environment and the remains of these organisms are referred to as organic matter.  Energy can be generated from these organic matters by producing biomass energy.

Biomass energy or bioenergy refers to the gas and electricity that is generated from biomass. Biomass energy is a renewable form of energy as defined by the IPCC (Intergovernmental Panel on Climate Change). The development of bioenergy could help mitigate the climate impact of using fossil fuels. The IEA (International Energy Agency) explains biomass energy as the most important renewable energy source, in 2017. Biomass can be converted into liquid transportation fuels that are equivalent to fossil-based fuels. The carbon from waste streams and biomass is reused into reduced-emissions fuels, bioproducts, and renewable power.

How is Biomass energy generated?

Biomass materials which are usually called biomass feedstocks are used as a source of energy. They can compose of waste products or can be grown mainly for their energy content. The energy from the sun is collected and stored in plants in the form of chemical energy. Biopower is carbon-neutral electricity produced from organic waste products. However, bioenergy or biomass energy is generated differently based on the kind of feedstock available.

How does Biomass energy work?

The wet feedstocks or animal waste are put into large sealed tanks, called digesters. These tanks are filled with bacteria that decompose the waste. Such wet feedstocks like food waste and animal waste rot in the sealed tank. As the waste decomposes, it produces methane gas which is called biogas. This methane gas is captured and burned to heat water which produces steam. The pressure of the steam spins the turbine which houses a generator to produce electricity. Also, the methane gas can be captured and injected into the national gas grid for cooking and heating use. Also, the gas when produced can be captured and burnt to generate electricity.

The dry feedstocks that are combustible are burnt in furnaces or boilers. Such dry feedstocks like wood and other forms of dry waste when burnt heat water to create steam. The energy from the steam is directed through pipes to drives a turbine which generates electricity. Conclusively, bioenergy is a very flexible source of energy and can be a great backup for weather-dependent renewable energy sources like solar and wind.

Biomass conversion

Biomass is converted through several processes to energy. It could be through direct combustion, chemical conversion, thermochemical conversion, biological conversion, biochemical conversion, pyrolysis, electrochemical conversion, thermal conversion, gasification, and anaerobic decomposition.

• Thermal conversion

Thermal conversion involves the use of heat to convert biomass into other forms of energy and products with or without the presence of oxygen. These processes include direct combustion, torrefaction, and pyrolysis.

Direct combustion

Direct combustion involves the burning of biomass in the presence of oxygen. The heat generated is used for heat, hot water, or with a waste heat boiler to operate a steam turbine. Direct combustion is the most common process for converting biomass to energy. Literally, all biomass can be burned directly for industrial process heat, heating buildings, water, and generating electricity in steam turbines.

Torrefaction

Biomass must be dried before it can be burned. The chemical process of drying out biomass is called torrefaction. It is heated to about 200°-320° Celsius during torrefaction. Hence, the biomass is completely dried out in a manner that it loses the ability to rot or absorb moisture. It becomes a dry blackened material and may lose about 20% of its original mass but still retains 90% of its energy. The biomass is then compressed into briquettes that repel water. Briquettes are very hydrophobic making storing them in moist places possible. These briquettes are easy to burn during direct or co-firing because they have a high energy density. However, the final product of torrefaction which is an energy-dense solid fuel is usually referred to as bio-coal.

Direct and Co-firing

For direct firing, most briquettes are burned directly. During the firing process, the steam produced powers a turbine. The turbine turns a generator, hence producing electricity. This electricity produced can be used to heat buildings or for manufacturing.

Also, biomass can be co-fired or burned with fossil fuel. In coal plants, it is most often co-fired. Co-firing eases the demand for coal reducing the amount of carbon dioxide and greenhouse gases released from burning fossil fuels.

Pyrolysis

Pyrolysis converts biomass feedstocks into oil, gas, and biochar in the absence of oxygen and under controlled temperature. Biochar is a type of charcoal that is carbon-rich and useful in agriculture. It enriches the soil and prevents it from leaching nutrients and pesticides into runoffs. Biochars happen to be excellent carbon sinks that are a reservoir for carbon-containing chemicals and greenhouse gases. The produced oil and gases from pyrolysis can be used to power a generator. Also, some technologies can make chemicals and diesel from the gases.

• Chemical conversion

Biomass is converted through chemical processes to produce liquid fuels. To convert it to other forms, a  set of chemical processes may be used. Chemical conversion involves using chemical agents to convert biomass into liquid fuels that are converted mostly to biodiesel. Biomass, however, can be converted into several commodity chemicals. There is a chemical conversion process known as transesterification. This process is used for converting animal fats, vegetable oils, and greases into fatty acid methyl esters (FAME). These fatty acid methyl esters are used to produce biodiesel.

• Thermochemical conversion

Biomass can be converted to produce solid, liquid, and gaseous fuels through thermochemical processes. These processes include pyrolysis and gasification. In both processes, biomass feedstocks are heated in closed pressurized vessels at high temperatures. These vessels are called gasifiers. The difference between gasification and pyrolysis is the process temperature and oxygen amount present during the process of conversion.

Pyrolysis

Pyrolysis involves heating feedstocks in a near-total absence of free oxygen to 400-500 degrees Celcius (800-900 degrees Fahrenheit). The absence of oxygen keeps the biomass from combusting and causes it to be chemically altered. This pyrolysis process produces fuels like bio-oil (dark liquid), biochar, renewable diesel, hydrogen, synthetic gas, and methane. The bio-oil (bio-crude or pyrolysis oil) produced by fast pyrolysis is processed by hydrotreating to produce renewable diesel, renewable jet fuel, and renewable gasoline.

Hydrotreating involves processing the bio-oil with hydrogen under elevated pressures and temperatures in the presence of a catalyst. Pyrolysis oil is a type of tar and can be combusted to generate electricity. Also, it can be used as a component in plastics and other fuels. Pyrolysis oil however is being studied by engineers and scientists as a possible alternative to petroleum.

Gasification

Biomass can be converted directly to energy through gasification. Gasification involves heating the feedstocks (mostly municipal solid waste) to 800-900 degrees celsius (1,400-1700 degrees Fahrenheit). The biomass is heated with controlled amounts of free oxygen or steam into the vessel to produce a hydrogen-rich gas called syngas and carbon monoxide. The molecules of the biomass break down and form syngas and slag.

Slag forms as a glassy molten liquid that can be used to make cement, shingles, or asphalt. Carbon monoxide and hydrogen makeup syngas. The syngas is cleaned of mercury, sulfur, particles, and other pollutants during gasification. Hence, the clean syngas can be combusted for electricity or heat. It can be processed into chemicals, fertilizers, and transportation biofuels.

Syngas (synthesis gas) can be used as a fuel for heating, generating electricity in gas turbines, and for diesel engines. The syngas can also be treated in order to separate the hydrogen from the gas. This separated hydrogen can be used in fuel cells or burned. Also, using the Fischer-Tropsch process, the syngas can be processed further to produce liquid fuels. Syngas can be converted into synthetic natural gas and methane to be used as a replacement for natural gas.

• Biological and Biochemical conversion

Biomass can be converted biologically to produce gaseous and liquid fuels. Many efficient biochemical processes have been developed to break down its molecules. Many of these biochemical processes can be harnessed and microorganisms are used to perform the conversion process in most cases. Such biological processes include fermentation, anaerobic digestion, and composting.

Enzymes like glycoside hydrolases are involved in the degradation of the major fraction of biomass. For more efficient degradation, recalcitrant biomass usually needs thermal treatment. This is why in biorefining applications, thermostable variants are now increasingly used as catalysts.

Biomass is fermented to convert it into ethanol which is used as a vehicle fuel. In anaerobic digestion, it is converted at diary or livestock operations and sewage treatment plants to produce renewable natural gas also called biomethane or biogas. Biogas can also be formed in solid waste landfills and can be captured from it. When renewable natural gas is properly treated, it has the same use as fossil natural gas.

Fermentation

Microorganisms are used to convert biomass feedstock biologically in fermentation. The feedstock is converted into combustible gases, chemicals, or biofuels like bioethanol and biobutanol. For example, through fermentation, molasses and starch are usually used as feedstocks to produce ethanol. The simple sugars such as maltose, glucose, and sucrose in these feedstocks are fermented into biobutanol or bioethanol.

The removal and presence of some by-products (e.g hydroxymethyl furfural) of hydrolysis reaction and osmotic pressure are the main operational variables affecting fermentation efficiency and ethanol yield. Hence, effective measures to improve the fermentation yield include:

• Selecting fermentation medium
• Selecting yeast type
• Detoxifying the hydrolysate
• Separating or removing the fermentation by-products

Moreso, biohydrogen can be produced efficiently by dark fermentation of biomass. In dark fermentation, facultative and specific anaerobic bacteria can also decompose the biomass. However, there are 2 different stages of dark fermentation:

• The first growing stage: In this stage, a high yield of hydrogen can be produced, followed by the production of butyric acid and acetic acid.
• The second slowly growing stage: In this stage,  less hydrogen and solvent are generated.

Nevertheless, dark fermentation doesn’t only produce hydrogen but produces valuable volatile fatty acid too. In dark fermentation, the major factors in determining the hydrogen production rate are:

• Inoculation source and enrichment method
• Substrate pretreatment
• Bioreactor parameters
• pH
• Temperature
• Hydraulic retention time (HRT)
• Hydrogen partial pressure

Recently, the combination of light fermentation and dark fermentation or bioelectrochemical systems has been investigated in order to obtain a higher hydrogen efficiency.

Anaerobic digestion

Anaerobic digestion is another biological process of using anaerobic bacteria for converting biomass into biogas. The primary factors in anaerobic processes that determine the biogas production efficiency include:

• pH
• Temperature
• Carbon to Nitrogen ratio (C: N)

If a biomass feedstock has high cellulose content, the efficiency of anaerobic digestion will be lower. Hence, feedstocks with high cellulose content are usually pretreated to improve the efficiency of biogas production. The feedstock is pretreated in order to degrade them into simpler compounds. These common pretreatment methods are:

• Mechanical grinding
• Fungal and Enzymatic hydrolysis
• Acid and Alkali chemical treatment
• Steam explosion

Also, it has been studied that adding exogenous catalysts to the fermentation process could further enhance the biogas yield and digestion rate.

Anaerobic decomposition

Anaerobic decomposition is a biological process where microorganisms (mostly bacteria) break down organic matter in the absence of oxygen. This process is an important biological process in landfills. In this process, biomass is crushed and compressed, creating an anaerobic or oxygen-poor environment.

Hence in such an anaerobic environment, the biomass decays producing methane. Methane, however, is a valuable energy source and can replace fossil fuels. Anaerobic decomposition can also be applied on livestock farms and ranches in addition to landfills. The animal waste and manure can be used as feedstocks and converted to sustainably meet the energy needs of the farm.

• Electrochemical conversion

Through electrochemical processes, biomass can be converted to electrical energy directly. This is through electrochemical (electrocatalytic) oxidation of the organic matter which can be performed directly in the following:

• A direct carbon fuel cell
• Direct liquid fuel cells such as a direct ethanol fuel cell
• A direct methanol fuel cell
• Direct formic acid fuel cell
• An L-ascorbic Acid Fuel Cell (vitamin C fuel cell)
• A microbial fuel cell

Indirectly, the fuel can be consumed also through a fuel cell system that contains a reformer. This reformer converts the biomass into a mixture of hydrogen and carbon dioxide before it is consumed in the fuel cell.

Biomass as fuel (Biofuel)

Biomass happens to be the only renewable energy source that can be converted into liquid biofuels like cellulosic ethanol, renewable hydrocarbon fuels, and biodiesel. Biodiesel and ethanol are the two most common biofuels in use. Biodiesel is produced by combining ethanol with animal fat, vegetable oil, or cooking fat. The fermentation of biomass that is rich in carbohydrates forms ethanol.

However, biofuels do not function as efficiently as gasoline. Hence they can be blended with gasoline to be able to power vehicles and machinery, efficiently. Also, they do not release the emissions associated with fossil fuels. Biofuels can be used in most vehicles and airplanes. Biofuels as transportation fuels help to alleviate demand for petroleum products. Also, it improves the greenhouse gas emissions profile of the transportation sector.

Biofuel types

• First-generation biofuels
• Second-generation biofuels

Biofuels are grouped based on the source of biomass into two main types:

1. First-generation biofuels: These biofuels are produced from food sources that are grown on arable land. Examples of such food sources are corn, sweet sorghum, and sugarcane. The carbohydrate content present in this sugar or starch-based feedstock is fermented to produce bioethanol. Bioethanol is an alcohol fuel that serves as an additive to gasoline or in a fuel cell to produce electricity. Bioethanol is widely used in the United States and Brazil. In Europe, biodiesel is produced from oils in crops like sugar beets, soy, oil palm, or rapeseed and is the most common biofuel in Europe.
2. Second-generation biofuels: These biofuels are produced from non-food-based feedstocks. Such examples of non-food-based biomass sources are perennial energy crops, municipal waste, wood chips, algae, and agricultural waste. The biomass used to make the fuels can grow on arable land but are byproducts of the main crop. Also, they are grown on marginal land. Waste from agriculture, industry, household and, forestry can also be used for second-generation biofuels. For instance, by direct combustion, using gasification to produce syngas, or anaerobic digestion to produce biogas. Cellulosic biomass gotten from grasses and trees (non-food sources) is being developed for ethanol production. Also, biodiesel can be made from leftover food products such as animal fats and vegetable oils. Secondary-generation fuels include a number of synthetic diesel/gasoline-equivalent, cellulosic ethanol, bio-butanol, and methanol.

Biopower

Biomass power is carbon-neutral electricity that is generated from renewable organic waste. The energy that is stored in biomass can be released to generate renewable electricity or heat energy. Hence, biopower technologies convert renewable biomass fuels into electricity and heat energy. The biopower technology uses one of these processes of bacterial decay, burning, and conversion of biomass to gas or liquid fuel.

Biopower can be generated through the following ways:

• The combustion or gasification of dry biomass or biogas (methane). Biogas is captured through anaerobic digestion.
• Cofiring of biomass and fossil fuels (mostly coal). This biopower means is a low-cost means of reducing greenhouse gas emissions and reducing air pollutants in power plants. It also improves cost-effectiveness.
• Thermal energy is often generated through the direct combustion of wood chips, wood pellets, and other sources of dry biomass.

Furthermore, the CHP (combined heat and power) operations usually represent the most efficient use of biomass. It utilizes about 80% of potential energy. These facilities capture the waste steam or heat from biopower production. Then pipe the captured heat or steam to nearby buildings to chillers for cooling or to provide heat.

In biomass power plants, wood waste and other waste are burned to produce steam. This steam runs a turbine to generate electricity or provides heat to homes and industries. Fortunately, new technologies like combustion engineering and pollution controls have advanced in a way that any emissions from burning biomass in industrial facilities are usually less than emissions produced when using fossil fuels.

Bioproduct

Bioproducts can be made from biomass in addition to electricity and fuels. Biomass can also be converted into chemicals. These chemicals can be used for making plastics and other products that are typically made from petroleum.

As in the production of energy, biomass can be an alternative to fossil fuels. It can also provide a renewable alternative for many industrial materials and products made from natural gas or petroleum. Products like lubricants, biobased foams, fertilizers, plastics, and industrial chemicals are a few of the possible examples.

Bioproducts are made with some component of biological or renewable materials from biological sources such as agriculture and food processing. Here are examples of bioproducts:

• Bio rubber and Biofoams from plant oils and latex
• Chemicals and resins such as paints, lubricants, and solvents
• Bioplastics made from plant oils and sugars
• Biocomposites are manufactured from agricultural and forestry bio fibers. These bioproducts are used in the production of automobile door parts and panels.
• Pharmaceutical antibodies and vaccines which are produced by genetically modified plant and natural source medicinal compounds
• Biocosmetics such as body creams, soaps, and lotions
• Biochar is carbon-rich and useful in agriculture. It enriches the soil and prevents it from leaching nutrients and pesticides into runoffs.

Biomass vs coal

Coal’s approximate chemical formula is  CH. The hydrogen (H) is converted to water and the carbon (C) to carbon dioxide when coal is burned. Energy is gotten from both hydrogen and carbon. Then one carbon dioxide (CO2) is emitted into the atmosphere.

Biomass, on the other hand, the chemical formula is CHO which is similar to coal with an oxygen atom added. However, the oxygen atom reduces the energy of biomass compared to coal. This is because the carbon is half-burned and that energy is not available. So when biomass is burned, energy is gotten from the hydrogen atom (H), and some energy is gotten from the further burning of CO. Then one carbon dioxide (CO2) is emitted into the atmosphere.

At this level, in terms of carbon dioxide emission, biomass is a worse fuel than coal. The reason that biomass is a low-carbon fuel is that biomass breathes carbon dioxide from the atmosphere. Hence storing it in its tissue. Though biomass emits carbon dioxide into the atmosphere when burned. It still absorbs exactly the same amount of carbon dioxide in the process of photosynthesis when it regrows. This cycle is carbon neutral.

Biomass vs Fossil fuel

Biomass comes from recently living organisms, in contrast to fossil fuels. Hence, the carbon in biomass can continue to be exchanged in the carbon cycle as carbon dioxide is released when biomass is burned. However, since it releases the same amount of carbon dioxide that the organic matter absorbed while it grew, it balances the carbon in the atmosphere.

Comparing biomass with fossil fuel. When burning fossil fuels, carbon dioxide is released adding more carbon dioxide into our current atmosphere. Hence breaking the carbon balance. Also, bioenergy dials back on fossil fuel dependence as fossil fuels are non-renewable forms of energy. Fossil fuels take years to produce because they are basically the remains of dead plants and animals buried underneath the crust of the earth. They are the leading sources of energy and generate a lot of power than biomass. Even though fossil fuels generate more power than biomass, they emit dangerous fumes to the environment. Hence causing severe environmental pollution which results in global warming and climate change. on this note, bioenergy is an alternative to reduce the dependence on fossil fuels and their adverse effects.

Nevertheless, it can’t be ignored that biomass is comparatively inefficient to fossil fuel. Ethanol, for instance, which is biodiesel is inefficient against gasoline. In addition, In order to function properly, it is usually blended with gasoline. Moreso, ethanol when used over time impacts combustion engines greatly. Biomass has a lower energy density than fossil fuels because about 50% of biomass is water. In the energy conversion process, this water is usually lost. Engineers and Scientists estimate that it is not economically efficient to transport biomass more than 100 miles from where it is processed. Hence, converting biomass into pellets can increase the fuel’s energy density. Thus making it more advantageous to ship.

Biomass Advantages

1. Bioenergy is a clean source of energy.
2. It helps to reduce foreign oil dependence.
3. Using biomass as an energy source helps to minimize the fill-up of landfills.
4. Biomass is versatile and can be used to produce diverse products.
5. Bioenergy dials back on fossil fuel dependence.
6. The emissions generated when biomass is burned are not harmful.
7. Biomass is a renewable source and is bountiful in nature.

• Biomass is a clean source of energy

Bioenergy is a clean renewable source of energy because its initial energy comes from the sun and plants. Even though bioenergy emits carbon dioxide, it is eco-friendly and clean. This is because, for its own growth, it captures the carbon dioxide back. Whereas the carbon dioxide emitted by fossil fuel is harmful because it can be a bad air pollutant if released into the environment.

• It helps to reduce foreign oil dependence

Biomass helps in foreign oil dependence reduction. Using biomass can help reduce dependency on foreign oil. This is because biomass can be used as biofuels which are the only renewable liquid transportation fuels available.

• Using biomass as an energy source helps to minimize the fill-up of landfills.

Bioenergy helps in waste management as it converts harmful wastes into useful energy. For instance, the waste that would have to fill up landfills can be collected for transformation and combustion into a valuable energy source.

• Biomass is versatile and can be used to produce diverse products

Biomass is versatile and can be used to generate thermal energy, renewable electricity, or transportation fuels. It can be used to produce diverse products like ethanol, biochar, biofuels, etc. Ethanol is derived from different crops and used to make alcoholic beverages and used as biodiesel to power most cars. There is no limitation to the series of ways biomass can be obtained and used, as long as there is an abundance of living organisms on earth.

• Bioenergy dials back on fossil fuel dependence

Bioenergy dials back on fossil fuel dependence as fossil fuels are non-renewable forms of energy. Fossil fuels take years to produce because they are basically the remains of dead plants and animals buried underneath the crust of the earth. They are the leading sources of energy and generate a lot of power than biomass. Fossil fuels examples are oil, coal, and natural gas.

Even though fossil fuels generate more power than biomass, they emit dangerous fumes to the environment. Hence causing severe environmental pollution which results in global warming and climate change. On this note, bioenergy is an alternative to reduce the dependence on fossil fuels and their adverse effects.

• The emissions generated when biomass is burned are not harmful

The carbon dioxide, biomass releases is harmless. These days, most energy companies find it difficult to control their carbon dioxide emissions. This is dangerous as these emissions can impact the ozone layer. Hence, leading to an increase in the greenhouse gases effect that can cause global warming and climate change.

Since bioenergy is totally natural, it doesn’t present adverse effects when used. Additionally, since trees and crops are sustainably farmed, they can offset carbon emissions as they absorb carbon dioxide through respiration. The amount of carbon that is re-absorbed in some bioenergy processes even exceeds the carbon emissions that are released during fuel usage or processing.

Using bioenergy has the potential to greatly reduce greenhouse gas emissions. Burning biomass and burning fossil fuels releases about the same amount of carbon dioxide. However, the difference is, fossil fuels release carbon dioxide captured by photosynthesis millions of years ago which is an essentially new greenhouse gas. Whereas, biomass releases carbon dioxide that is greatly balanced by the carbon dioxide it must have captured while growing.

• Biomass is a renewable source and is bountiful in nature

Bioenergy is stored within living matter and can be harvested when needed unlike other renewable sources of energy like wind or solar. Since biomass products emanate from living matter, they literally cannot run out as long as living creatures are on earth. Also, biomass products will continue to exist as far as someone is available to transform the living matter and waste products into useful energy.

Algae or plants biomass can easily regrow in a short period of time and are always available. Likewise, municipal solid waste, trees, and crops are available consistently and can be managed sustainably. Hence biomass is a bountiful and renewable source in nature. For instance, chicken droppings are the main source of biomass fuel in the UK. Countries like the United States and Russia with acres of forest have lumber in bountiful supply as a source of bioenergy.

Biomass Disadvantages

1. Biomass in comparison to fossil fuel is inefficient.
2. In comparison to fossil fuels, biomass has a lower energy density.
3. Utilizing biomass effectively may lead to environmental degradation.
4. Biomass combustion needs a lot of space.
5. Methane gas emissions due to biogas production may be harmful to the environment.
6. Burning biomass could release some pollutants.

• Biomass in comparison to fossil fuel is inefficient

Biomass is comparatively inefficient to fossil fuel. Ethanol, for instance, which is biodiesel is inefficient against gasoline. In addition, in order to function properly, it is usually blended with gasoline. Moreso, ethanol when used over time impacts combustion engines greatly.

• In comparison to fossil fuels, biomass has a lower energy density

Biomass has a lower energy density than fossil fuels because about 50% of biomass is water. This water is usually lost in the energy conversion process. Engineers and Scientists estimate that it is not economically efficient to transport biomass more than 100 miles from where it is processed. Hence, converting biomass into pellets can increase the fuel’s energy density. Thus making it more advantageous to ship.

• Utilizing biomass effectively may lead to environmental degradation

The use of trees as feedstocks results in environmental degradation. This is true in the context that in order to satisfy a country’s energy need, the amount of lumber needed may be outrageous. To power up an electricity plant or satisfy a country’s energy needs, a significant chunk of forest would have to be cleared. Over time, this habit would eventually interfere with the natural habitats of most animals and plants, as well as leading to huge changes in the area’s topography.

So biomass can become non-renewable, once feedstocks are not replenished as quickly as they are used. Take a forest for instance that can take hundreds of years to re-establish itself, even though the time frame is still a much shorter time period than a fossil fuel such as peat takes to replenish itself. For 3 feet of peat to replenish itself, it can take 900 years. Forested areas that have matured for decades are able to remove more carbon than newly planted areas. So, the advantages of using the wood from trees for fuel are not balanced by the regrowth of the trees if forested areas are not sustainably cut, re-planted, and given time to grow and remove carbon.

Furthermore, to develop, most biomass needs arable land. Meaning that land used for biofuel crops like soybeans and corn will become unavailable to provide natural habitats or grow food.

• Biomass combustion needs a lot of space

Biomass combustion needs a lot of space as the burning of biomass products needs a big chunk of land. A large landmass is required for the ease and convenience of burning. This is because biomass emits gasses like methane to the environment. Hence, it is normally produced in areas that are far away from residential areas.

• Methane gas emissions due to biogas production may be harmful to the environment

Utilizing human and animal waste as biomass feedstock may save a lot regarding carbon dioxide emissions. However, methane gas would increase significantly. This methane gas could impact the ozone layer. In other words, using bioenergy has its own fair share of pollution in the environment.

Additionally, when working with waste products, the smells can be disgusting and may attract unwanted creatures like pests. These attracted pests may pose grave health dangers like bacteria infestation.

• Burning biomass could release some pollutants

Some particulates and pollutants like carbon monoxide, nitrogen oxides, carbon dioxide, and others are released when burning biomass. Burning biomass can create smog and may even exceed the number of pollutants released by fossil fuels. This can happen if the pollutants released are not captured and recycled.