Table of Contents
What is biomass energy?
Biomass energy produces heat and/or electricity by incinerating organic material that comes from either plants or animals. The organic material from animals consists of manure from cows, horses or chickens. And many indigenous populations in the Andes mountain range of South America collect waste from their llamas and alpacas. Once it’s collected, it is dried into a petrified state, then incinerated to heat their homes, boil water and cook food. In other parts of the world, the same process may occur. For organic plant material, the process of incineration is the same. Organic plant material, once dried, can become a fuel used to generate energy in the form of heat1.
For many parts of the developing world, burning organic plant material to generate heat for daily life is still common. In the developed world, biomass was the primary source of energy until the mid-to-late 1800s. Now, biomass energy is produced through the incineration of human waste, like garbage. Many municipalities in the United States may have their biomass plants to help create the electricity needed to meet the energy demands of their citizens. Biomass energy plants are also used with other renewable energy sources to help produce electricity at the main facility. For example, a wind farm may work with a biomass power plant to produce electricity when the wind is either too slow or too high to run the wind turbines.
What is used to create biomass energy?
Different types of organic plant material can be used for biomass energy production through photosynthesis. When the plants are alive, they harness the power of the sun to give themselves life. When they die, that energy remains within the plant until it’s burned. For example, if a tree is turned to firewood and then burned to heat a home, the tree’s original energy absorbed through photosynthesis is released through combustion to heat the house.
Here are some of the examples of the different types of plant organic material commonly used to produce biomass energy:
- Crops and waste produced from agricultural food processing: Often, leftover waste is not used in food production — like the stalks and husks of corn. When dried, these types of crop waste can be incinerated to produce biomass energy. Typical crops include soybeans, sugar cane, switchgrass, algae and corn.
- Wood: Firewood, wood pellets, wood chips, lumber, recycled furniture, waste and sawdust from lumber mills, and the leftover pulp from paper mills can all be used as biomass fuel.
- Municipal solid waste: Many of our products come from paper, cotton and wool products and can be incinerated to create biomass energy. Additionally, yard waste, like lawn clippings and leaves, can also create biomass energy.
Is biomass a renewable source of energy?
Yes, biomass energy is considered renewable. The main reason biomass can be viewed as a renewable energy source is because there is a constant supply of material to burn. In another sense, biomass energy is seen as renewable because the energy source that creates organic plant material comes from the sun. Biomass energy sources also can be grown or produced in a relatively short amount of time. When you compare that to the time it takes the Earth to have sources of fossil fuels, the planet can produce biomass resources as fast as it uses them. Not only is biomass energy renewable, but it could also be considered carbon-neutral. If trees can be planted as quickly as they are burned to produce biomass energy, the carbon dioxide produced during combustion will be absorbed by the living trees, forming a continuous cycle2.
What are some examples of biomass energy?
Biomass energy can come in many forms, like human and animal waste or organic plant material. Different types of organic plant material include firewood, wood pellets, wood chips, lumber and the waste produced from sawmills and paper mills. Additionally, crops like corn, soybeans, sugar cane, switchgrass and algae can be used in one form or another to produce biomass energy.
How does biomass energy work?
Biomass energy is a process of combustion. No matter the organic material used, it’s through combustion that the energy is released. Whether it’s through the creation of biomass fuels (ethanol and biodiesel) or the design of a biomass electric facility, when the organic material is incinerated, the energy is released. Here is a quick breakdown of how a waste incineration plant works3:
- Preparation: All the waste collected to potentially enter the waste incineration facility needs to be sorted to remove metallic and oversized items. Once sorted, the garbage is shredded to maximize efficiency in preparation for combustion.
- Combustion: The sorted and shredded waste is sent into an oxygenated combustion chamber, where it is heated to temperatures that range from 1,800 to 2,200 degrees Fahrenheit.
- Energy generation: When the garbage is combusted, the gases produced are cooled with water to create steam. The steam is used to turn turbines which are attached to generators. The generators produce electricity from the turbine motion.
- Pollutants control: When the steam and gases are cooled, they are treated through several EPA-mandated pollution control systems. These systems contain scrubbers, filters, and precipitators to reduce harmful gases that would otherwise affect the atmosphere.
- Release: The treated steam and gases are released into the atmosphere.
This is an example of one of the more complicated processes of biomass energy production. A more straightforward example is simply burning wood in a wood stove to heat the interior of a home in the winter. Either way, biomass is a dependable source of energy that is both renewable and carbon-neutral.
What are the advantages of biomass energy?
Biomass is a unique form of energy production; however, it is not new technology having been around since the beginning of humanity. Here are some of the main advantages of using biomass in its modern form to produce energy4:
- A widely available renewable source of energy: Whether it’s trees, crops and agricultural byproducts, animal manure, or the garbage produced by our society, the materials needed to produce biomass energy are readily and abundantly available.
- Carbon-neutral: When biomass energy is produced outside of a facility, say at a family campfire, the carbon dioxide produced from the combustion of organic plant material is absorbed by the plants currently living on Earth. As long as the plants are replaced as quickly as they are consumed, ideally, the entire process should be carbon-neutral.
- Less waste in landfills: By burning our waste rather than simply collecting it into landfills, we can help reduce the adverse environmental effects that landfills create.
There are other advantages to using biomass energy, these are simply some of the most impactful benefits worth discussing.
What are the disadvantages of biomass energy?
As we discussed the main advantages of biomass energy, it is only fair to discuss some of the main disadvantages. Here are some of the most impactful disadvantages of using biomass to generate energy:
- Can create harmful gases: Burning biomass fuels can produce many different types of gases. Although biomass can be considered carbon-neutral, the process can still make other dangerous gases such as methane. Regulators in the energy sector are working to implement systems that emit fewer gases.
- Poor use of resources: Biomass fuels like ethanol and biodiesel are produced through harvesting corn and other agricultural products for the sole purpose of creating energy. Some argue that with so many in the world suffering from food scarcity and starvation, would those resources be better used to feed vulnerable populations rather than burning them for vehicles?
Every type of energy source is going to have its advantages and disadvantages. Despite its drawbacks, the benefits overwhelmingly outweigh the negatives.
How much energy is produced by biomass?
Biomass is used across many sectors of the economy in the United States. You can see biomass energy used in the industrial, transportation, residential, commercial, and electricity generation sectors. In 2020, approximately 4.9% of energy consumption in the U.S. could be attributed to biomass energy.
How efficient is biomass energy?
In general, biomass used for traditional uses like heating homes and cooking food may be considered an inefficient use of resources. However, it is through biomass facilities and power plants that combustion is much more efficient. For biomass to be highly efficient, it can be used alongside other forms of energy production, known as co-firing, which is done by adding biomass material as a partial substitute for fuel in highly efficient coal boilers, which helps decrease harmful emissions5.
Is biomass energy sustainable for the future?
Yes, biomass energy is sustainable for the future; however, it cannot be solely relied upon to meet the entire planet’s energy needs. Biomass energy is used with other renewable energy sources like wind, solar, and hydroelectric energy to provide energy in the power grid. Biomass is a part of the future of our planet as we move away from fossil fuels and toward a future of clean and sustainable energy.