While we strive to deal with the imminent decline of world oil supplies we also need to consider the impact of oil alternatives. Biofuel production has been held up as a solution to our oil dependence. Biofuels have also been promoted as a replacement for oil, implying that we will be able to maintain our lifestyles even after the oil supply has run dry.
This is certainly a worthy goal, but how realistic is this and at what cost will this fuel be produced? The basis of biofuel production is the conversion of plant sugars into ethanol, which can then be used as a fuel. There are two broad types of sugars available in plants, and the choice of which to use as the fuel source directly affects the profitability of the fuel generated from the plant.
The first type is simple sugars, with one or two sugar molecules joined together. These are the sugars that we digest from plants, which are we get our energy from. These sugars are mainly present in the fruits of plants. An example of this is the corn cob. This part of the corn plant is high in energy. Making ethanol from this part of the plant is profitable since the sugar molecules are easily converted into ethanol with the help of organisms such as yeast.
The second source of sugars in the plant is in the plant body itself, the tough fibrous material called cellulose. This is comprised of the same sugar molecules present in the fruit, but are bonded together in long strands. These strands are very difficult to break down into simple sugars and involve complex enzymes such as cellulase. These can be produced commercially but this is an expensive process. The result of converting cellulose into ethanol is both a lower yield and a higher cost per unit of fuel, but its great advantage is that any plant matter, even cardboard and paper, can be converted into fuel. There is no need to reduce the availability of food with cellulose conversion.
Presently almost all biofuel production is carried out using the simple sugars from corn cobs or similarly sugar rich plants such as sugar cane. Clearly, by using these crops to make fuel we are reducing the availability of food. With global demand for food rising and prices rising with it, it seems irresponsible to be using what little agricultural land we have to be making oil substitute fuels.
We cannot afford to supplement our fuel supply by sacrificing food production. By researching improved methods for producing cellulase or other substances that do the same job we could indeed have a genuinely clean source of energy that will be continuous and not damage the planet.
This is certainly a worthy goal, but how realistic is this and at what cost will this fuel be produced? The basis of biofuel production is the conversion of plant sugars into ethanol, which can then be used as a fuel. There are two broad types of sugars available in plants, and the choice of which to use as the fuel source directly affects the profitability of the fuel generated from the plant.
The first type is simple sugars, with one or two sugar molecules joined together. These are the sugars that we digest from plants, which are we get our energy from. These sugars are mainly present in the fruits of plants. An example of this is the corn cob. This part of the corn plant is high in energy. Making ethanol from this part of the plant is profitable since the sugar molecules are easily converted into ethanol with the help of organisms such as yeast.
The second source of sugars in the plant is in the plant body itself, the tough fibrous material called cellulose. This is comprised of the same sugar molecules present in the fruit, but are bonded together in long strands. These strands are very difficult to break down into simple sugars and involve complex enzymes such as cellulase. These can be produced commercially but this is an expensive process. The result of converting cellulose into ethanol is both a lower yield and a higher cost per unit of fuel, but its great advantage is that any plant matter, even cardboard and paper, can be converted into fuel. There is no need to reduce the availability of food with cellulose conversion.
Presently almost all biofuel production is carried out using the simple sugars from corn cobs or similarly sugar rich plants such as sugar cane. Clearly, by using these crops to make fuel we are reducing the availability of food. With global demand for food rising and prices rising with it, it seems irresponsible to be using what little agricultural land we have to be making oil substitute fuels.
We cannot afford to supplement our fuel supply by sacrificing food production. By researching improved methods for producing cellulase or other substances that do the same job we could indeed have a genuinely clean source of energy that will be continuous and not damage the planet.
About the Author:
Get more information on this important topic in the What Is Biofuel section of Roger Vanderlely's website, www.green-planet-solar-energy.com. You can also read about the associated issue of fossil fuels, how they are produced and what the problems and benefits are of their use.
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