Biomass energy is a renewable source of fuel that can be used to heat homes, power vehicles or as an alternative for fossil fuels. This article helps you understand the basics of biomass energy or bioenergy. It takes you through the bioenergy advantages and disadvantages and enables you to make the right choice.
There is nothing known as “Perfect”.” – Albert Einstein
It could not be truer for energy resources. Now we do have a slew of energy sources to choose from but if one scores well on one count, it goes down in another. Ultimately, it is up to us, as consumers, to weigh the pros and cons and arrive at the best choice.
For example, consider solar power. It is free. It doesn’t pollute. What more can one ask for? But can we choose solar power based only on these points? Not exactly.
If you don’t take into consideration its high upfront cost, availability of enough sunlight, and access to licensed contractors for installation, you will get caught somewhere in the middle.
The same can be said about all energy sources, including biomass.
What is biomass?
Biomass is the organic matter we get from plants and animals. Until the 19th century when we discovered fossil fuels, coal and oil, biomass used to be the main source of energy.
- Agricultural produce and waste
- Wood and wood waste
- Biogenic waste
- Animal and human excrement
Plants convert the sun’s energy into chemical energy through photosynthesis. Animals and humans get this chemical energy through the food they consume. This chemical energy stored in the biomass can be directly converted to heat energy by burning it. It can also be converted into other forms of energy through various processes.
This involves heating biomass to very high temperatures in the absence of free oxygen. The fuels produced include charcoal, methane, hydrogen, renewable diesel, and bio-oil.
This is a method to process bio-oil. It is heated with hydrogen with a catalyst present at very high pressures and temperatures. The resultant fuels are renewable gasoline, renewable diesel, and renewable jet fuel.
In this process, the biomass is heated to temperatures up to 1700°F in the presence of limited free oxygen and/or steam to get syngas, a hydrogen and carbon monoxide-rich gas. Syngas can be used as a fuel directly or processed further to separate hydrogen from it or extract liquid fuels.
Using the fermentation process, biomass can be converted to ethanol, fuel to run vehicles. When biomass is subjected to anaerobic digestion, it produces renewable natural gas or biogas. Well-treated biogas can be used in the same way as natural gas from fossil fuels.
Biomass energy: Pros and cons
Biomass energy or bioenergy converts the chemical energy present in biomass to usable forms of energy through various processes. Biomass, being the organic waste generated by our various activities, is easily available and free of cost.
It is natural to ask why we have not adopted this energy source. By switching from fossil fuels to bioenergy, we can have our cake and eat it too! It has to be a win-win.
However, things are not as simple as that. It is true that if bioenergy replaces fossil fuels, the adverse impacts of fossil fuels such as pollution and resultant climate change can be controlled. Moreover, we are running out of fossil fuel fast and we need to find an alternative. Bioenergy may be the answer we are seeking.
However, bioenergy comes with its own set of limitations and disadvantages. So, before we jump into the bioenergy bandwagon, we need to consider it from all angles.
Here are the advantages and disadvantages of biomass fuels.
Advantages of Bioenergy
Bioenergy was the first energy source that humans used after the discovery of fire. Easy availability drove its usage, even without much knowledge about energy and energy sources.
Now, when we are trying to wean ourselves from the dependence on fossil fuels, bioenergy is a good choice for many reasons.
1. Bioenergy is renewable.
In the hot debate of renewable vs nonrenewable, bioenergy wins hands down. As it is derived from plants and animals, replenishing biomass is a nonissue. Trees can be planted and animals can be raised to replenish the supply of biomass.
2. Bioenergy is carbon neutral.
One of the main cons of fossil fuels is their carbon footprint. This is the main contributing factor to global warming and climate change. Bioenergy is carbon neutral as fuel production is an integral part of the carbon cycle.
At the time of burning, biomass releases carbon dioxide. But this is offset in equal measure by plants when they take in carbon dioxide during photosynthesis. Thus, making the process carbon neutral.
3. Bioenergy can reduce our reliance on fossil fuels.
Our dependence on fossil fuels is not easy to get rid of. But we are forced to look for alternatives because of their contribution to climate change and limited availability. At the rate we are using now, we will run out of fossil fuels in a few decades.
As better alternative energy sources become popular, we look forward to loosening the stranglehold of oil and coal. Biomass energy is a good alternative for those who have easy access to biomass and connected technologies.
4. Bioenergy is versatile.
Using various processes and technologies, biomass can be converted into a wide range of fuels to satisfy a variety of needs. It is the most versatile and adaptable among alternative energy sources.
Ethanol, biodiesel, methane gas, hydrogen, renewable natural gas, the list goes on.
5. Biomass is easily available.
Almost like the sun, wind, and water, biomass can be found across the world. Unlike fossil fuels, there is no threat of running out of biomass supply. However, unlike the sun, wind, and water, it doesn’t replenish on its own. We must take adequate action to maintain the abundance of biomass.
6. Bioenergy is less expensive.
Easier availability of biomass, its low cost, and cheaper technologies involved mean producing bioenergy is cheaper when compared to most energy sources, especially fossil fuels.
7. Bioenergy can reduce the waste problem.
Most of the waste generated worldwide is biodegradable. Instead of letting it create a problem for the civic authorities, it can be put to better use by generating bioenergy. Waste that would otherwise go into landfills and create hassles for humans and the environment is used to generate bioenergy. This means fewer landfills and more land for humans.
8. Bioenergy can be produced onsite.
The monopoly of large power companies can be broken by switching to bioenergy. You no longer need to depend on the grid for your energy needs. Nor do you need to cope with the soaring energy rates.
If you have the basic requirements in place, you can meet your energy needs with the bioenergy you generate onsite.
Disadvantages of Bioenergy
There are always two sides to a coin. Bioenergy indeed is an alternative worth considering replacing fossil fuels. However, it also comes with some disadvantages that you need to be aware of.
While some disadvantages result from fuel usage, others are from its production process or application.
1. Bioenergy is not as clean as it is made out to be.
Carbon neutrality is indeed true for bioenergy. However, when it is burned, carbon is not the only harmful by-product. This can result in polluting the environment, though not as extreme as fossil fuels. However, it is the worst polluter among renewable resources.
The polluting aspect of bioenergy is a huge setback to its claim as an alternative to fossil fuels.
2. Bioenergy extraction involves high costs.
Though less expensive when compared to fossil fuels, among other renewable energy sources, bioenergy is far from the cheapest option. When other alternatives like solar, wind, or water energy are feasible options, biomass is not worth the investment.
The cost of bioenergy includes the cost involved in maintaining biomass resources and replenishing the biomass used up. It also includes the cost of transportation and the cost of setting up the machinery.
3. Bioenergy can lead to deforestation.
Maintenance is one key aspect that makes bioenergy renewable. When enough attention is not paid to this aspect, bioenergy will lose its edge as an alternative to fossil fuels. Failure to replenish the biomass used can result in extensive deforestation.
Large-scale adoption of bioenergy can aggravate environmental degradation and crisis. Massive felling of trees for generating biomass, even if replanted, can affect the habitat of wildlife. Moreover, replanting trees to replace the ones cut down for biomass generation may not be feasible if bioenergy is adopted on a large scale.
4. Bioenergy needs large land spaces to grow biomass.
In densely populated areas of the world, setting aside enough land space to grow biomass to keep up its supply for bioenergy production may not be possible. This places restrictions on where bioenergy plants can be built. Space requirements dent the prospects of bioenergy among renewable resources like solar and wind.
5. Bioenergy requires large quantities of water.
To grow biomass, good irrigation infrastructure and ample water availability are preconditions. This is sure to raise the cost of the setup and result in water scarcity for the consumption of humans and wildlife.
The question also arises why water cannot be used directly to generate energy. As we know already, it is less polluting than bioenergy.
6. Biofuels are not as efficient.
Though they are carbon-neutral, the efficiency of biofuels is not comparable with fossil fuels. Often biofuels are mixed with small quantities of fossil fuels to ramp up their efficiency. This takes the advantage right out of the equation.
7. Bioenergy technologies are still in the development stage.
We have indeed come a long way from burning wood for cooking and heating. However, much more needs to be done to smooth out the wrinkles in the different stages of bioenergy generation. Especially when there are better alternatives available, bioenergy naturally takes a back seat.
The amazing prospects of bioenergy are clearly evident. Carbon neutrality is its main selling point. When compared to fossil fuels, it scores high on almost all aspects. However, there are some aspects that need improvement, especially its efficiency and the cost and land space requirement. Better technologies can help in its adoption on a large scale.
Until then, it is still a feasible option for small-scale operations. It offers a lucrative use for the waste generated at the same time saves on energy bills.