Ethanol, for those that are unaware, is pure alcohol that can be derived through a number of processes and a number of primary sources. The one that I will be focusing on today is the most common source used in the United States today, that being ‘Corn Ethanol’. Breaking down the bulk of the science used, basically the natural starch in corn is converted to combustible form of alcohol and thus, a gasoline that can be used in vehicles.
Sugar can also be used as is the common practice in all gasoline sold Brazil today, who happens to be the world’s largest sugar producer.
The practical flaws in this approach to developing what is renewable fuel fall into two distinct areas:
Economically: The current process uses corn resources that would otherwise be used as a food source to now produce gasoline. This adds increased pressure to increase corn prices as there is heightened demand. This manipulation of market prices would be stark in a drought year when the resource produced was stretched to meet original demand, without added demand for corn to be used as a fuel. This would economically make ethanol uncompetitive from a price point with traditional fuel sources.
Brazil has overcome this situation by producing ‘Sugar ethanol’ fuel at a price and performance that is superior to that of fossil fuels and thus in economically unstable times there isn’t a reversion back to original fuel sorces. This is also due to the fact that Sugar as a source of ethanol produces a much more output than that of corn.
Environmentally: Put simply, a lot of fossil fuel is burned to produce not a lot of renewable energy. For example, the process to grow the corn involves the following: A seeder to cover every hectare planting the crop, a spreader is later required to again cover every hectare spreading fertilizer (perhaps twice per crop cycle). Following this a harvester will be required to retrace every sewn hectare of land to strip the crop. All of these steps require the harvesters and tractors to burn copious amounts of diesel to produce the corn, all to produce a significantly smaller amount of ethanol fuel. Add to this the cost to transport seed and mine the fertilizer and it becomes a blatantly flawed system.
The way Brazil makes it work is that the cost of producing sugar is much lower for them as the cost of labor is much, much lower and the output of ethanol generated from sugar is considerably higher than that of what corn produces. Corn is 10-20% Greenhouse gas savings vs petrol whereas sugar is 87-96%.
I believe going forward there will definitely be a place for renewable ethanol fuel, but only if it doesn’t come at the cost of a strained food source and as long as it makes economical and environmental sense to produce. Research is already progressing towards converting animal manure (humans included) into a fuel source. There is also the prospect of removing noxious weeds and converting them into ethanol. Both products that are otherwise unwanted, able to be transformed into practical energy source… a much more logical approach in my opinion.