We explain what biofuels are and how each one is obtained. In addition, the advantages they present and types of biofuels.
What are biofuels?
Biofuels are those fuels that They are obtained from biomass or organic waste (hence its name). Biomass is organic matter from a plant or animal.
Biomass is part of the set of renewable energies, which are found in limited quantities in nature and they are produced in slow and longer periods than it takes to consume them. Diesel and gasoline, for example, are made from plant or animal fossils that take millions of years to form while their consumption is immediate.
Biomass is an energy source that, since the invention of automobiles (at the beginning of the 20th century) has become indispensable. It is used, in the industrial field, for the generation of electricity and heat. It is very common for it to be used, then, for heating homes.
As the years go by, The price of biomass has risen considerably especially based on the concerns that have arisen worldwide as a result of the emission of CO2 (Carbon Dioxide) and its impacts on the environment. Despite this, Defenders of environmental care also question the use of biomass since its production results in deforestation.
Within the biofuels from the plant world (which are the most used, especially for the operation of automobiles), they can be differentiated into two large groups:
- Bioethanol. This energy source is produced from oats, corn, wheat, beets or sugar cane and is used instead of gasoline.
- Biodiesel This biofuel, on the other hand, is used instead of diesel and is made from soybeans, palm, rapeseed or sunflower.
See also: Alternative energies
How are biofuels obtained?
Biofuels are obtained from organic waste or biomass. They are the result of different chemical or physical processes which transform those wastes or matter. Below are some examples of how to obtain them:
- Biogas It is the result of a mixture of gases that decompose organic matter through bacterial actions.
- Biodiesel. In this case, different chemical processes are used, such as transesterification from methanol or ethanol (the most used). In this process, fat molecules are converted into esters.
- Bioethanol. This biofuel, on the other hand, is obtained from the fermentation of non-crystallizable monosaccharides in the manufacture of both beets and sugar cane. It can also be obtained from the hydrolysis or fermentation of the starches of certain cereal grains. To carry out this fermentation, yeast is used. The process of obtaining this biofuel has three key stages: fermentation, distillation and dehydration.
Advantages of biofuels
Although it is true that environmental specialists warn of the consequences of the use of biofuels, such as deforestation (including Greenpeace), one of the main advantages of biofuels is the reduction of carbon dioxide emissions, in relation to fossil fuels. According to different studies, 80% of biofuels reduce carbon dioxide emissions by 30%.
Furthermore, another benefit of biofuels is the production of soot and suspended particles, which are much lower than those of other energy sources and that affect the respiratory system of people and animals.
Finally, there are those who, when comparing the relationship between the energy invested and that obtained, assure that the results are much more auspicious in the case of biofuels than fossil fuels.
Types of biofuels
There are different kinds of biofuels, if you take into account their source. In this sense we can find the following types:
- Primary They are those biofuels that come from firewood, gases from landfills, crop or animal waste. The impact (positive or negative) on the environment will depend on the procedures used to obtain energy from these materials.
- Secondary These are those energy sources that are classified according to their generation. In this sense, the following classes are found:
- First generation. They are those biofuels whose production process does not require the hydrolysis of the carbon source (for example, bioethanol and biodiesel). The raw materials used are all food sources.
- Second generation All sources other than food, so as not to put food safety at risk.
- Third generation. Those raw materials that are vegetables, but are not used as food.
- Fourth generation. Although this category is in full development, this includes biofuels produced from bacteria that have been genetically modified, for which carbon dioxide is used.
References
- “Non-renewable energies” in Solar Energy.
- “Biofuels” in National Geographic.
- “Agrofuels, a solution that causes problems” in Greenpeace.
- “Biofuels” in How do you see?