What are Biofuels?
Biofuel refers to the liquid fuels produced from biomass (organic matter). Ethanol and biodiesel are two most common forms of biofuel. Biodiesel is made from vegetable oil or animal fat whereas ethanol is derived from corn starch and sugar cane.
Where do biofuels come from?
Biofuels can also be sourced from materials such as wood, agricultural products along with their by-products and waste. Research is still being carried out in search for new sources of biofuel and to improve existing methods of production.
How do Biofuels work?
Biofuels work just like gasoline which can be burned to produce energy which can be used to run cars or heat your homes. The only difference here is that biofuels are sourced from recently harvested plants. This is a major leap in reducing the dependency on fossil fuels.
Step-by-Step Production Process of Biofuels
There are few basic steps which are followed while making ethanol on a large-scale:
- Fermentation of sugars
However, the production of biodiesel involves a process called trans-esterification. It involves a chemical reaction of long-chained fatty acids with alcohol which produces fatty-acid esters.
Both of these fuels can be used to fuel cars, trains and aviation.
The biggest problem faced by these biofuels is not being as efficient and cost-effective as petroleum fuels. Therefore, they are usually used as blends with fossil fuels.
How does biofuel energy work?
To have a better comparison, ethanol is 30% less efficient as per unit of volume than normal fuel. This means that more pure ethanol is required to obtain the same gas mileage as we get from using gasoline. The use of ethanol is restricted to automobiles, trucks and motorcycles for now, specifically for engines which can adapt to ethanol.
Most of the time, ethanol is used as a mixture in gasoline. Mixed fuels are labeled with E- as prefix at the gas stations, followed by the percentage of ethanol mixed in the mixture. For example, E70 means that the mixture contains 70% ethanol and 30% gasoline.
When ethanol is mixed with gasoline, it increases the octane levels of the fuel which helps the engine to have a higher performance.
The mixtures which have low percentage of ethanol in them are also called gasohol; these do not require any alterations to the engine. As the percentage of ethanol in fuel gets higher, the engine requires more modifications.
The efficiency of biodiesel is also less than that of gasoline. However, it highly depends upon the quality and blending of the fuel. Biodiesel is labeled with B- as prefix at the gas stations, followed by the percentage of biodiesel in the fuel mix. For example, B20 is 20% biodiesel in diesel fuel.
The lower the percentage of biodiesel added, the lower the need to modify the engine. If we use pure biodiesel, in the long run that would lead to some performance and maintenance problems. These maintenance problems can be taken care of. Biodiesel is more common in European Union than in the US.
Read more on Biodiesels: Biodiesel; Definition, Pros and Cons