What Are Biofuels?
Any kind of fuel that is derived from biomass, or plant matter and animal waste, such as manure from cows, is known as biofuel, also referred to as agrofuel. It is also derived from industrial and municipal waste, forestry, and agricultural residues. In other words, they are a source of energy from plants.
Biofuels can be used as fuels for transportation and for creating electricity. Fuel used for transportation are pyrolysis oils, biomethanol, biodiesel, and ethanol.
Unlike other sources of fuel like nuclear fuels, coal, and petroleum, biofuels are renewable sources of energy. The advantage they have is that they are 'carbon neutral', which means that even though carbon is released in the atmosphere when they are burned, the plants had already absorbed that carbon.
They are therefore regarded as 'CO2 neutral', that is they do not add to the level of carbon dioxide in the atmosphere. This is the reason they are touted by environmentalists as a means of reducing CO2 in the atmosphere, by replacing energy sources that are non-renewable with agrofuels.
Using this type of energy from plants is dependent on various factors, chiefly the feedstock available, and the kind of energy that can be utilized locally.
Biofuels are of three types: gas, liquid, and solid. Amongst these, the liquids are used as fuel for vehicles, of which the two most common ones are ethanol, a substitute for petrol, which is made from grain, sugar, or corn, and biodiesel, produced from oil seeds.
Biofuel Types That Are In Use Today
The interest in biogas as a substitute for natural gas is gradually growing. It is particularly useful since its composition is almost identical, hence the burners that are used for natural gas can be used for biogas too. It can be made from animal or plant waste, or by combining the two.
Various methods are used to produce it, depending on the quantity involved and the starting material. The best method has proven to be a mixture of both. While the vegetable waste produces the hydrogen and carbon necessary, the animal waste generates the nitrogen required for the growth of the bacteria.
This was perhaps the first amongst the alternative fuels to caught the attention of the general public. One of the greatest pros of biodiesel is that it can be used in the current vehicles without an adaptation required, or very little of it. For this reason, biodiesel is a compromise, but as far as the energy scales are concerned, it balances positively.
Higher energy from plants is available which can generate higher yields in kW-hr per area, however the advantage of having a fuel that is completely compatible with the current engines and fuel technology, makes it particularly attractive.
This type of biofuel is produced from biomass, sugar cane, or agricultural crops. Cars that run on it are governed by the very same physics laws as those that use gasoline. Which means, due to the process of combustion, both of them produce CO2. However, there is a vital difference.
Since burning ethanol actually results in recycling CO2, because the process of photosynthesis while the plant had been growing had already removed it from the atmosphere. Whereas, using diesel or gasoline actually injects additional amounts of CO2, which had been fixed underground in the deposits of oil for millions of years.
Benefits Of Biofuels
Biofuels have many benefits, while they also contribute to the achievement of energy security and an economy that is more sustainable.
- Compared to diesel and gasoline, they are much cleaner fuels and do not cause as much pollution.
- Since Ethanol, which is used as an additive to gasoline, provides oxygen, it results in gasoline burning more fully, thus creating less smog.
- Biodiesel does not produce any sulfur or any other emissions of toxic matter.
- They lower the emissions of greenhouse gas, since the carbon contained in them has been absorbed from the soil and air, within the natural cycle of carbon.
- Producing biodiesel and ethanol locally results in reducing the dependence on oil that is imported, thus improving energy security.
- They help in cushioning the impact of sudden fluctuations in the supply of oil, thus acting as a protective factor against high prices of fuel.
- The plants that produce them create jobs, while also offering economic opportunities locally, for R&D and engineering companies, construction crews, feedstock processors, and farmers. The money that is invested stays in the region, which results in increasing incomes across the economy.
- Farmers also derive benefits due to new alternatives in crops, which helps in improving their profitability and stability.