Biofuels are fuels obtained from biomass (agricultural crops such as palm oil, sugar cane, soybeans, etc.) or from organic waste. The fuel generated is a liquid fuel obtained from vegetable oils that can be used in vehicle engines.
This kind of fuel is considered non-renewable energy. The generation and recovery time of the fields is less than that of consumption.
The biofuels generated can be of two types, bioethanol and biodiesel:
Bioethanol, a gasoline substitute. Ethanol produces uses sugar cane, beet, corn, wheat, and oats. (cellulosic ethanol)
Biodiesel, a substitute for diesel. Biodiesel is produced from plants such as sunflower, rapeseed, palm or soybean.
This type of fuel was presented as an alternative to oil extraction. The objective of reducing the emission of millions of tons of carbon dioxide into the atmosphere. Even so, the result was not what was expected and its use is being highly criticized by environmental platforms.
What are the pros and cons of biofuel?
Pros of biofuels
Mobility compared to other alternative energy sources
Currently, more “radical” alternative energy technologies such as solar energy and wind energy have one big problem: mobility.
On the other hand, biofuel, it is quite easy to transport. It is stable and has a rather high "energy density". It can be used with minor modifications to existing technologies and infrastructure.
Currently, biofuels cost the same on the market as gasoline. However, there are more benefits to using biofuels as it is a cleaner fuel and produces less emissions when burned. Biofuels can be adapted to existing engine designs to perform well in all conditions.
However, this fuel is better for engines, it lowers the overall cost of controlling engine pollution and therefore requires less maintenance.
Cons of biofuels
Restrictions on regional suitability
Plant feedstock for biofuels is likely to be grown in certain regions. This is due to a number of reasons.
When choosing a region for the production of plant materials, one should take into account:
Water use - the less water is used to grow a crop, the better, as water is a limited resource.
Invasiveness - crops that kill native plants and are difficult to control can threaten biodiversity and severely damage the ecosystem of a region.
Fertilizers are essential nutrients for plants. Some plants require fewer organic resources than others.
Climate - In some areas, it is simply not possible to grow biofuel crops.
The problem with growing crops for fuel is that they will take up land that could be used to grow food. In a world with an ever-growing population, the problem of land availability for agricultural purposes is becoming more and more acute.
Restriction on land-use change
When clearing the land from local vegetation to grow raw materials, the blow to the environment is dealt from three sides:
The habitat of animals and micro-ecosystems is destroyed.
In the process of clearing the area from local vegetation, energy consumption increases, so production is very energy-intensive. It is associated with a large amount of pollutant emissions during processing.
The consumption of fertilizers is increasing, which will pollute the soil and through its waterways and the entire environment.
Land-use changes for biofuel production have significant drawbacks. For biofuel production, the best solution is to use existing land, but this reduces the amount of land for food purposes.
Restriction in the composition of gasoline/diesel
As a transport fuel, in modern cars, ethanol and biodiesel can only be used in conventional gasoline or diesel engines, respectively. And only in small quantities, no more than 10%. If this threshold is exceeded, then environmentally friendly fuel can safely harm the fuel system of the car and its engine.
Some biofuels can lead to pollution of the environment with hazardous substances for which there are currently no standards.
The consumption of some types of biofuels can emit greenhouse gases such as carbon dioxide or carbon monoxide.
Each new generation aims to overcome the drawbacks of the previous generation. All generations have two goals in common: not to harm the production of food crops and to simplify the process.
In this way we distinguish the following generations:
First-generation biofuels, which are generated from food crops. Food crops are explicitly grown for fuel production.
Second-generation biofuels, which are made from various types of biomass. Any source of organic carbon is considered biomass. Biomass is derived from plant and animal fats materials.
Third-generation biofuels. It is about generating biofuels through the use of algae. The production of algae to harvest oil for biofuels has not yet been carried out on a commercial scale. This type of fuel does not imply a decrease in food production.
Fourth-generation biofuels. They are manufactured using non-arable land.
What influence do biofuels have on climate change?
According to the Nobel Prize winner in Chemistry, Paul Crutzen, the gases emitted by biofuel crops increase global warming. Biofuels have an impact on the greenhouse effect.
Biofuels present the same greenhouse gas emission problems as carbon dioxide as fossil fuels. Some biofuels pollute even more.
The fields where they are cultivated do not regenerate fast enough to meet the demand for this fuel. For this reason, it cannot be considered a renewable energy source.
Are biofuels more efficient?
At the energy level, they do not suppose any improvement either. The Energy Return Rate (ERR) is less than 1 or very close to it. this means that the energy balance is zero or negative. That is, it takes more energy to produce it than is obtained from its combustion.