The going will be tough for the future of biofuels, but with effort, they could just save us.
Petroleum is currently the most widely used form of fuel for combustion engines in the world. Second to that is the diesel engine. But what if all of that could change? Our world is possibly on the brink of a major readjustment in production, manufacture and sources of our goods, including our fuel sources due to increased energy demand and environmental awareness. Scientists are working to keep up with this demand, and biofuels could provide the answer to the problem. A study called “Biodiesel Production from various feedstocks and their effects on the fuel properties” published in 'The Journal of Industrial Microbiology and Biotechnology; Official Journal of the Society for Industrial Microbiology', looked into the properties of these ‘biofuels’, particularly biodiesels, and proposed how they could work for humanity and what must be improved before this could happen. The methods introduced and ideas set across are an incredible step forward in our goal to become more environmentally friendly.
Biodiesel is a new, renewable source of energy, that is, obviously, of biological origin. Feedstocks of biofuels are primarily vegetable oils. However, other options, such as waste cooking oils, restaurant greases, soapstock and animal fats are also being considered (though they will be harder to test at this point and must be significantly improved in terms of efficiency). Vegetable oils have been used since the invention of the diesel engine in 1900. Though until 1980, they were written off due to engine complications. The oil crisis in 1970 brought back the idea of using biodiesels and since then, the idea has been greatly expanded. The main problem faced when using biofuels was their high viscosity and low volatility. The chemical structure of diesel, along with its lighter molecular weight, makes it a much better candidate than biofuels at this point in time. But research and testing is being conducted constantly to try to even out the playing field between the two.
The problem with biodiesels at this point in time lies primarily in the area of cost. In the current economy, the price of vegetable oil is too high to be considered for fuel. The other options, as listed above, would cost less, but they do not function as well as refined oil and fatty acid sources, like the vegetable oil. Regular diesel is, at this point, the most cost efficient and best for the engines. However, besides the cost, biofuels have many advantages. When burned, exhaust emissions decrease drastically: 20% in CO, 30% in HC, 40% in particulate matter and 50% in soot emission. NO (and similar) gases do increase by 10-15%, but even this can be compensated for by retarding the fuel-injection timing (Canakci and Sanli).
The study also examines the ways in which biodiesels can be improved to close the distance between them and diesels. Of the four methods currently being experimented, trans-esterification seems to be the most promising. This involves the splitting of triglycerides in fatty acids and oils to make them more efficient and closer in chemical makeup to diesel. When trans-esterification works, the viscosity of biodiesels is lowered and their cetane number and heating value are saved, thus making them more efficient. Biodiesels are biodegradable, non-toxic, almost sulphur-less, non-aromatic and environmentally friendly, even more so when they have gone through trans-esterification. They are also a much better engine lubricant than regular diesel. Concentrating even 1% of diesel fuel with biodiesels significantly increases the lubrication of the fuel, therefore increasing engine productivity.
Production of biofuels around the world has greatly increased in the past few years. According to the study, the production in the 3 years prior to 2008 in the European Union increased two and a half fold. The European Union and the US are the two main producers of biofuels around the world, and for good reason, as they are also main consumers of all different types of fuels. If north America, Europe and other major consumers were to increase their biofuel usage by even a tiny amount, we could decrease the effects of emissions significantly, perhaps even bring us that much closer to the Kyoto protocol (and other) goals, which are proving difficult to reach.
Biofuels and their production are expensive. The economic situation for them has gone from bad to worse in the last few years (Canakci and Sanli). The study suggests that in order for them to become a reality, they must become more economically viable; in other words they must be able to compete with diesel. They must be equivalent in as many ways as possible. Viscosity, density, cetane number, flash point, cold-flow properties and oxidation stability are all factors being evaluated, and are all very important to the productivity of biodiesels. This study explains how much more viable biofuels would be if these factors were to be improved upon.
The world is at its peak in terms of sustainability. All options are being considered, and as far as this study goes, it is well worth it to look into biofuels. They may have their disadvantages, but even now, the future looks bright. If biodiesels were to be improved even a little bit, we may well have a major factor in the solution to our deteriorating habitat.
Canakci, M, and H Sanli. "Biodiesel Production from various feedstocks and their effects on the fuel properties." Journal of Industrial Microbiology and Biotechnology; Official Journal of the Society for Industrial Microbiology (2008): 13 March, 2008. Web. 14 Oct 2010. http://www.springerlink.com/content/e562773v17970310/fulltext.html
By: Rebecca Fyfe
October 14, 2010
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