- slide 1 of 5
Times have been changing. No distance is too great and no loved ones too far. Just of think someone you'd like to see and in a matter of few hours, you can reach your destination. Thanks to airplanes. However, just consider the amount of fuel that is used by these airplanes – 1 gallon every second! With this, all the steps taken for climate change, global warming and depleting resources receive a back seat. However, the advancement of technology has helped us mitigate the harmful effects of burning carbon fuels. This is how biofuels came into the picture.
- slide 2 of 5
Biofuels for Airplanes
Due to the huge consumption of fuels by airplanes, biofuels are certainly good news. However, there is no fixed formula to produce biofuels as the term biofuel covers all of the fuels obtained from biomass. This biomass (solid biomass, liquid fuels and biogases) is broken into various components and re-combined to produce apposite fuel. Different processes involve either thermal conversion or biochemical conversion or a combination of both to break-down the biomass. However, standard biofuels are not suitable for aircraft. Research and development suggests that biofuels need to have properties similar to crude oil-based fuels to be used for aircraft.
- slide 3 of 5
Types of Biofuels used on Jets
Plant oils such as jatropha oil, coconut oil, palm oil & camelina oil are hydro-treated to convert them into aviation fuel, a type of fuel known as the Hydro-treated renewable jet (HRJ) fuel. Biofuel made from palm oil is twice as expensive as regular aviation fuel; the reason being, massive deforestation is necessary to obtain palm oil. However, the actual amount of biofuel required for flights remains unknown; the only estimate being Virgin’s test flight in the year 2008 that used five percent of biofuels (which required 1, 50,000 coconuts as well babassu nuts) for just one flight.
Sugar based biofuels can also be converted into aviation fuels after some processes. Various techniques are under development to utilize this fuel. Biobutanol and isobutanol process involves fermentation by bacteria such as E.coli. Although this faces some technical difficulty, it could be overcome using synthetic biology. Another fuel, Biogasoline undergoes thermal conversion so that it can be suitable for aircraft. Bio-Forming engages a series of treatments on biomass which is followed by an aqueous re-forming process that breaks down organic hydrocarbons into hydrogen, carbon dioxide, alcohols and other components. After this, the fuel is abstracted from water. A small pilot-plant making such bio-fuel is being operated in the United States, with plans to switch to a full-fledged one in near future. Lastly, biocrude can also be made suitable for aviation. The process involves exposing of biomass to high temperature using a catalyst in the absence of oxygen. This type of biofuel has already been refined by four test flights.
Another process known as Fischer-Tropsch gasification is also utilized to make biofuels suitable for aircrafts. It exposes biomass or fossil fuels to high-temperatures which turns them into synthetic-gases, followed by conversion into liquid hydrocarbons and then liquid fuel that can be used in airplanes. This technology is being used in South Africa to produce road-transport fuel from coal, which received certification in 2008. This synthetic fuel can be obtained from natural gas, a coal-biomass mixture, or biomass alone.
The production of synthetic fuel from biomass requires a huge cost, ample amount of energy for conversion, cost of feedstock and most importantly, large reserves of biomass which currently is practically impossible. However, there is another option for this known as the pyrolysis process. Here the capital cost is low and the size of the plants required also is comparatively smaller. But again, this option comes with its disadvantages, mainly environmental pollution.
- slide 4 of 5
Biofuel from Algae
Biofuels can also be produced from algae; an environmentally sustainable option. Research is being conducted on utilizing algae to produce various types of biofuels, inclusive of HRJ fuel & biocrude for the aviation sector. A test flight has already been done based on biofuel blended from algae & jatropha. But scientists predict that this biofuel will be commercially available only around 2020 as it faces certain problems like production of the right type of algae, resources to grow algae (including the water body, either expensive closed-reactors or natural ponds) and risks to marine life etc.
In a nutshell, biofuels for airplanes have major repercussions which need to be reconsidered. It remains sure that aviation biofuels can see the light of the day in the near future. The option is not entirely impossible if technical barriers are given some consideration. Going by the quantity of vegetable oil required, biomass probably would be a better option. If vegetable oils are used to produce biofuel, it will again lead to deforestation and the whole idea to use biofuels will go to waste. The increase in pressure on forests has lead to depleting groundwater, eroding soils as well as extinct bio-diversity and jungle fires. Thus, there’s a need to create proper balance between destruction and plantation which will answer all the problems. But indeed, aviation biofuels will bring a revolution and change the current scenario, allowing people to meet their loved ones in a matter of few hours and also without harming the ecosystem.
Use of Biofuels in Airplanes
The increase in carbon emission from the airline industry is taking a toll on the environment leading to problems such as climate change and various natural calamities. To fight against this, the airline industry is in the process of taking some drastic steps which will change the way you fly.