Biomass Energy

Living things have been used to generate energy since the stone age when cavemen used wood to cook food and protect themselves from cold and animals. Did you know that the use of wood to generate heat energy is called biomass energy? Biomass is an organic material which comes from plants and animals.

Table of Contents

What is biomass energy?
Ways to produce biomass energy
Advantages and disadvantages
Practice problems
FAQs

What is Biomass Energy?

Biomass energy can be produced from a variety of organic wastes, including wood, garden debris, agricultural waste, animal waste, sewage and municipal solid waste, food scraps, and animal faeces. The energy that can be created from biomass may be utilised in a variety of ways, for example, as a form of fuel for cars, an alternative source of energy for different types of businesses, and to generate electricity.

There are two types of biomass energy:

Renewable
Non-renewable

The sun is the primary energy source used in the creation of biomass. Through photosynthesis, plants transform solar energy into chemical energy for food, consume it as fuel for their growth, and then turn it back into energy.

Ways to Produce Biomass Energy

There are several ways to produce biomass energy, such as the following:

Thermal Conversion

Energy can be produced from burning biomass through thermal conversion. Thermal conversion includes heating the biomass to burn, dehydrate, or stabilise it. Raw materials like municipal solid waste (MSW) and waste from paper or timber mills are among the most used biomass sources for thermal conversion.

The common processes which produce different types of energy are as follows:

Direct firing and co-firing

The steam created through the direct firing process drives a turbine that rotates a generator and generates electricity. The electricity generated can be utilised for generating heat in buildings or for industries.

Additionally, biomass can be co-fired alongside fossil fuel. Co-firing avoids the requirement to construct additional biomass processing facilities. This minimises the overall amount of carbon dioxide and additional greenhouse gases emitted by the combustion of fossil fuels.

Pyrolysis

Pyrolysis is the process of heating biomass to temperatures ranging from 200° to 300° C (390° to 570° F) in the absence of oxygen.

A black liquid known as pyrolysis oil, a synthetic fuel called syngas, and a solid byproduct called biochar, are obtained from pyrolysis.

Pyrolysis oil is a form of tar commonly referred to as bio-oil or biocrude. It can burn to produce electricity.

Syngas could be turned into methane and utilised as a natural gas substitute.

Biochar is a carbon-rich substance that can be used in agriculture. By enhancing the soil, biochar protects it from losing nutrients and toxins to wash away. Additionally, biochar makes a superior carbon sink.

Gasification

A biomass source (often MSW) is heated to above 700°C (1,300°F) through the gasification process while being exposed to a set amount of oxygen. The molecules degrade, releasing syngas and slag.

Syngas can be converted into automotive biofuels, additives, and fertilisers, and they also can be burned to generate heat or power.

Slag is a molten, glassy liquid. It can be used to create asphalt, cement, or shingles.

Anaerobic decomposition

Anaerobic decomposition is the method by which microbes, typically bacteria, decompose substances in the absence of oxygen. Biomass decomposes and yields a valuable source of energy, methane, in an anaerobic environment. This methane can replace fossil fuels.

Biofuel

Biomass is the only form of renewable energy which can be processed into liquid biofuels like ethanol and biodiesel. Biofuel has been employed for running automobiles.

High-carbohydrate biomass, such as sugarcane, wheat, or corn, is fermented to produce ethanol. Ethanol and vegetable oil, animal-based fat, or residual cooking fat are combined to create biodiesel.

Biochar

The pyrolysis byproduct biochar is useful for both environmental and agricultural purposes. Charring biomass preserves its carbon content by sequestering it. Biochar additionally helps to improve soil quality. It is permeable. Biochar absorbs and holds onto water and nutrients when used back into the soil.

Black Liquor

When wood is turned into paper, a poisonous, high-energy liquid known as "black liquor" is produced. Most black liquor consumed by paper mills is used to power their facilities.

Hydrogen Fuel Cells

Hydrogen, which could be chemically extracted from biomass and utilised to produce electricity and fuel automobiles, is abundant in nature. Hydrogen fuel cells fuel transport vehicles, lifting equipment, boats, and submarines, and they are currently being researched for use in aeroplanes and other automobiles.

Advantages and Disadvantages of Biomass Energy

There are both pros and cons to using biomass energy:

Advantages

Some of the advantages of biomass energy are as follows:

Biomass energy is a type of renewable energy.
Biomass is a dependable resource that can generate energy whenever needed.
The fact that biomass is plentiful is one of the main advantages of biomass energy.
Biomass energy transforms garbage to create something productive that would normally remain in the dumpsite.
Biomass can be regarded as a carbon-neutral energy source since it integrates into nature's carbon cycle, whereas standard fossil fuels may not.

Disadvantages

The disadvantages of using biomass energy might be as follows:

The cost of producing biomass energy can be very significant.
Biomass energy facilities require a large amount of room, primarily for storage.
Numerous other greenhouse gases, including nitrogen oxides, carbon monoxide, and methane, are also released when burning wood and other biomass fuels.
While biomass energy is a renewable energy source, this isn't particularly advantageous for the environment.
Relying solely on biomass energy could have adverse impacts on the environment.
Compared to other sources of energy, biomass energy is less effective.

Practice Problems

Q1. Which of the following can be used to replenish nutrients in the soil?

A. Coal ash
B. Biofuel
C. Biochar
D. Soda

Answer. C. Biochar can be used to replenish nutrients in the soil. It is porous in nature and improves soil quality by absorbing nutrients and water in the soil.

Q2. Biomass can be used to make ___________.

A. Biochemicals
B. Automobile fuel
C. Fibres
D. Chemicals

Ans. B. Biofuels are significantly used in several vehicles. It is also used to generate heat energy and electricity.

Q3. Production of bio-ethanol is through fermentation of starch compounds and _______.

A. Sugar
B. Alcohol
C. Acid
D. Methane

Ans. A. Sugar is used along with starch compounds fermented for the production of bio-ethanol.

FAQs

Q1. Which ecosystem contains the most biomass?
Ans. The ecosystem in forests certainly contains the highest biomass concentration. This is due to the size and robustness of the trees. This is because wood and wood waste are the most important biomass energy sources in the modern world.

Q2. What is the unit of biomass?
Ans. The typical unit of biomass is grams per square metre (g/m2).

Q3. Which state is the largest producer of biomass in India?
Ans. The leading states for biomass power generation are Chattisgarh, Madhya Pradesh, Gujarat, Rajasthan and Tamil Nadu.