Ethanol production relies on the fermentation of natural plant sugars, making it possible to produce ethanol from nearly any plant substance, including waste material. Plants with a high natural sugar content, such as sugarcane, are ideal for fermentation, but according to afdc.energy.gov, 90% of ethanol in the United States is currently produced from corn.
Ethanol Production and Distribution
The sugars in a feedstock, such as corn, are fermented using a process called biochemical conversion. First, the feedstock is ground into flour and cooked with water and enzymes. Yeast is then added to the mixture to begin fermentation. The resulting substance is placed in a ‘molecular sieve’ which distills pure ethanol from the mixture. The substance that remains after distillation can be sold as an ingredient in certain animal feeds to eliminate waste and reduce material costs.
A majority of ethanol produced in the US is shipped via truck or rail. Using pipelines to ship ethanol over large distances is a highly effective method, but the unique properties of ethanol require the use of costly, specially designed pipes.
E10 and E85
Ethanol is often blended with gasoline in different ratios; the most popular blends are E10, which contains 10% ethanol, and E85, which contains 85% ethanol. Nearly any internal combustion engine can utilize E10 fuel, and this fuel can be found at an increasing number of traditional gas stations across the country. E85 can only be used by uniquely designed vehicles, called ‘flex-fuel vehicles’ (FFV), which can run on ethanol, gasoline, or any mixture of the two. Although more gas stations are offering E85 fuel than ever, it remains difficult to find in many locations.
Ethanol Benefits
Ethanol can be produced domestically in large quantities, which reduces the risks associated with relying on foreign sources of energy. Since it is alcohol-based, ethanol burns clean and emits significantly smaller amounts of greenhouse gas than gasoline and other traditional fuels. According to fueleconomy.gov, vehicles fueled by E85 experience no performance lags compared to vehicles fueled by gasoline.
Drawbacks of Ethanol
Ethanol is currently not available in many regions, making the purchase of flex-fuel vehicles out of the question for a large number of environmentally conscious consumers. Ethanol’s lower energy content compared to gasoline provides fewer miles per gallon than vehicles running on gasoline. Add the fact that ethanol cannot carry you very far to the fact that it is not widely available and you have the perfect recipe for a vehicle breakdown many miles away from the nearest ethanol fueling station.
Other Alternative Fuels
Ethanol is a strong contender in the race to fuel the future, but it is not alone in its quest to rid the world of the hazards of traditional energy sources. Other alternative fuels such as hydrogen, natural gas, and biomass are making great progress towards becoming commercially viable fuel solutions in international markets.