Biomass is currently one of the latest sources of renewable energy. Together with solar energy and wind power it makes a convincing argument for not using fossil fuels anymore and rather reverting to natural processes to obtain the energy / power that we need. Biomass consists of plant matter that is specifically grown for its ability to generate heat or electricity. Mostly this would mean that Biomass consists of dead plant matter, but plants that are still alive can also generate heat and are therefore also included in the term Biomass.
In order to produce the heat or electricity, the biomass needs to be directly incinerated and fed fuel to keep it burning. This means that biodegradable waste can therefore also be included if it is able to burn and generate heat or electricity. Unfortunately fossil fuels also fall in this category as they are traditionally used to burn in order to generate electricity.
The main purpose of investigating biomass energy is to find sustainable, renewable energy in order to eliminate the usage of fossil fuels for the purpose of generating electricity. In the following sections we will explore what biomass energy is, how it works, its sources and it potential. It is always important to make decisions such as these based on facts rather than emotional arguments.
What is Biomass?
When looking at biomass, it is important to remember that biomass consists mainly or dead or even living biological matter. In the context of biomass energy this biological matter is usually plant-based. It is carbon based and consists of molecules of hydrogen (as well as small amounts of oxygen), nitrogen and various other smaller molecules of other chemicals. Although biomass is generally plant-based, animal matter can also be included for the benefit of the chemical molecules that it can contribute.
Why use Biomass?
One of the biggest advantages of using biomass is the fact that it is a renewable energy source. Making use of biomass energy means that the carbon emissions usually associated with burning fossil fuels are drastically reducing, thereby diminishing the carbon "footprint" left behind. This also means that it can contribute to reducing the so-called greenhouse effect, as well as the production of the so-called greenhouse gasses. All of this in turn helps to prevent and minimise global warming.
When using biomass for energy purposes, the carbon produced when burning is turned into carbon dioxide when it combines with the oxygen around it. When emitted into the air, the carbon monoxide is ‘inhaled' by living plant matter. This, in turn, then results in oxygen being released into the atmosphere, reducing the carbon production that the burning of fossil fuels causes. This means that biomass makes more biological and environmental sense when thinking about sustainable and renewable energy.
Types of Biomass
Scientists recognize four types of biomass:
- Wood and agricultural products: This consists of so-called ‘home-grown' products such as wood logs and chips etc. It is important to note that almost any biological matter can produce biomass energy. Agricultural biomass come from waste products such as fruit pits, corn cobs etc.
- Solid waste: This is everyday waste / ‘garbage' that can be used to produce energy. It is easily burnt and many plants are already using this method of generating energy.
- Landfill gas: This is methane gas that is produced during the decaying and rotting process of biological matter. Landfills are artificial environments for these processes to take place, but are just as effective in generating gas that can compete successfully with the so-called ‘natural gasses'.
- Alcohol fuels: Liquid fuels such as ethanol and methanol are produced using biological matter such as wheat, corn and potatoes. Once again, this is done during the decaying and fermentation processes.
Sources of Biomass
There are 5 distinct sources of biomass: Garbage, Wood, Waste, Landfill gases and Alcohol fuels. The biggest source of biomass currently is garbage. The day-to-day waste of households hold the biggest potential for biomass energy as it is already habit to incinerate garbage. Wood comes in at second place with the so-called ‘black liquor' its biggest contributor. Black liquor is the waste product of the pulping process.
Hot on its heels is waste with it main contributors being municipal solid waste (MSW), manufacturing waste and landfill gas. In the last place are the liquid fuels such as ethanol and methanol which are the result of the fermentation of certain plant types such as corn and sugarcane. Together these sources of biomass have the potential to produce significant amounts of energy that could successfully replace the use of fossil fuels such as coal as a source of energy.
How Biomass energy works?
The process of producing biomass energy starts with the process of photosynthesis in plants. When plants absorb sunlight, the process starts with breaking down the components of sun, air and water into products that the plant uses to grow and thrive. One waste product of the process is oxygen which the plant releases into the air. This is why plants are so important as they "clean" the air of carbon dioxide and release oxygen back into the air.
The next step comes when the plant dies and becomes a waste product. As a waste product plant matter (as well as animal waste) can be collected and burned to generate energy. Because these products are all completely natural, the waste product from the incineration process is carbon dioxide which can easily be absorbed by other, living plants. The carbon emissions are greatly reduced and in many cases not even produced.
Potential for Biomass Energy
Studies by the United States of America show that the use of biomass energy can increase sharply over the next 20 - 30 years. They are already producing 1.2 percent of their total energy needs through the use of biomass energy. It is also predicted that four percent of their transportation energy needs (fuel) can be produced in 2010 with an expectation of up to 20 percent in 2030.
The Department of Energy also believes that biomass energy can be producing up to 14 percent of the USA's energy consumption by 2030. The potential for biomass energy is huge and is making significant inroads in proving to be the most economic solution to the quest for renewable and sustainable energy sources.
Converting Biomass to Energy
In order to convert biomass into energy, scientists and energy plants can use 1 of 3 conversion methods:
- Thermochemical conversion takes place when plant matter is heated but not burned. The heating process helps the plant matter to break down into its natural gasses, liquids and solids. These are then processed to become the energy producing fuel such as methanol and alcohol that is required. The gasses are collected to help fuel the turbines that generate energy.
- Biochemical conversion is when bacteria etc. is used to break down the plant matter. It makes use of the fermentation process to break plant matter down into solids, gasses and fluids. Once these have been achieved, they are processed and turned into energy generating fuel.
- Chemical conversion is the process that converts oils (like canola oil) into useful fuels - even petrol and diesel for trucks. Algae has also been known to produce the so-called ‘biodiesel' for trucks and is acknowledged as a better source than the cooking oil from restaurants.
Biomass Energy Pros and Cons
As with any fuel, there are many pros and cons attached to it.
On the pro side, the obvious benefit is that the biomass fuel is sustainable and renewable. Although they are as effective as fossil fuels, they don't cause much pollution. Using the garbage that would normally go into a landfill helps to reduce the pollution to the environment. From a political point of view, the use of biomass energy reduces countries' need to depend on foreign countries for their oil supply.
The cons of biomass energy aren't immediately visible. The first concern is that biomass energy does release greenhouse gasses into the atmosphere. However, the amount is considerably less than that released by fossil fuels. There are special cleaning requirements for a biomass energy plant. There is also the question of how much it costs to erect a biomass energy plant compared to the cost of a fossil fuel energy plant.
Although there are also cons to the use of biomass energy, it is clear that it is still a more sensible approach to the constant threat of global warming. It may be a little too late to repair the damage already done, but it is still possible to overlook the "inconveniences" of biomass energy in order to prevent future damage and disaster.
Biomass Energy Finance
Biomass energy is still a controversial topic in many governments. There is clear competition between the supporters of fossil fuel energy and biomass energy. For this reason governments are wary of offering their support to biomass energy initiatives too quickly. In a domino effect, private investment is tied to the government's policies on biomass energy and can therefore not be tapped into easily.
Earlier this year the UK government has relented and offered their support for biomass energy pioneers, offering to finance both the non-fuel as well as the fuel aspects of building plants. This unlocks the doors for private investors into the industry. There is an biomass energy estimated £13 billion in private investment money that has been waiting for the government to change its policy on biomass energy.