Discovering and developing alternative fuels that will help us decrease our dependence on petroleum has become a high priority in recent years. This is what the world of biofuel is all about: industrial biotechnology research that explores the potential of different organic materials to create fuels that are both more sustainable and less harmful to our environment than traditional fossil fuels.
The concept of using organic material as a source of fuel is by no means a new one. Those biofuels known as “primary” (or unprocessed) biofuels—organic material in more or less its natural form—have been used for thousands and thousands of years; the most typical example of a primary biofuel is firewood. However, it is only recently that advances in technology have allowed us to explore “secondary” biofuels, which are fuels that are derived or processed from different organic sources. The two types of biofuels most commonly used today are biodiesel, which is derived from vegetable oil or animal fats; and ethanol, which is created with crops like sugar cane, soy beans, or other plants that contain significant amounts of sugar and starches.
Today, many different potential sources of biofuel are at varying stages of research and development, and each has advantages and disadvantages. Some of the top possible sources currently being explored or produced include:
Basically a type of plant fiber, cellulose can be found in everything from switchgrass to trees to corn stalks. Experts estimate that roughly 1.3 billion tons of cellulose material for potential biofuel use could be harvested in the United States alone, an abundance that could make it a tremendous biofuel source. However, before cellulose can be used as a fuel, it must be broken down into sugars—something that is more challenging than it sounds, given that the natural properties of cellulose are specifically designed to resist this process. Scientists at the US Forest Products Laboratory in Wisconsin are currently working to develop the necessary technology to break down cellulose, and thus tap into this enormous potential fuel source.
Algae and algal oil
Algae have a distinct advantage over other biofuel sources because of where they grow. As algae are water-based crops, they do not need to compete with agricultural crops for land space, an issue that is a source of considerable controversy in the production of other biofuel sources. In addition, algae are able to store up to half their body weight in fat, and they have an incredibly rapid growth rate. Although they have a fast growth rate that could keep up with long-term high demand, there’s one big problem with using algae for biofuels: the quicker algae grow, the quicker they become overcrowded, which usually results in massive die-offs. At present, the most significant obstacle to commercial algal oil production is the lack of a way to effectively control and maintain the growth of algae.
Used as a source of ethanol, corn is currently the biggest biofuel in the US. This also makes it the biggest target for those who oppose the use of food crops for fuel. But even without this controversy, experts believe that although corn may be one of our best biofuel options at present, it is not viable over the long term because the process to convert it to ethanol is both expensive and requires large amounts of energy.
Another popular biofuel source, soy is transformed into fuel through a relatively easy and inexpensive process called trans-sterification, in which oil is squeezed from the seeds and converted into products like biodiesel and jet fuel. However, as is the case with corn, the use of soy as a fuel is subject to a great deal of controversy, given that it is a dietary staple for many people worldwide.
Globally, sugar cane is the second most widely used source of ethanol after corn, but that is expected to change in the coming decade. Biofuel made from sugar cane has the advantage of using more of the plant than soy- or corn-based fuels, which only use the seed. In addition, sugar cane-based biofuels have helped tropical countries like Brazil, where the plant grows in abundance, to become energy independent. However, more widespread use of sugar cane in biofuel production may be limited, given that it can only be grown in particular climates.
Canola is commonly found throughout Canada and the United States, and like soy, it is easy and inexpensive to produce and burns much cleaner than petroleum. However, the big question about using canola oil for biofuel is whether it would be possible to produce enough to satisfy demand. In order to produce a significant amount of fuel, many acres of land would be needed, which would again raise the problem of taking land away from food crops.