The use of ethanol as a fuel dates back as far as back as 1908 when Henry Fords first model Ts ran on 100 ethanol. The engine could run on standard gasoline or ethanol that at the time was made completely from corn. To this day ethanol produced in the United States is still made from corn. Corn is used in today's ethanol because it is the most widely produced crop in the United States. Also, there is not a shortage of corn. The use of corn, going into ethanol production, has gone from 5% in 2000, to as much as 30% in 2008. (Goldemberg 2087) By the year 2022, the Renewable Fuel Standard mandates that 136 million meters cubed of bio-fuel must be used. (Hira 6929) With these policies, sugarcane ethanol will be able to compete with corn ethanol if import tariffs are low enough. The United States and Brazil are the two largest producers of ethanol. Brazil entered the ethanol market during the 1970s when they established the PROALCOOL program in response to the oil crisis of 1973 which sent gasoline prices soaring throughout the world. At the same time, the Brazilian government gave incentives to improve ethanol distribution, to produce ethanol vehicles and production facilities. Brazil's consumption of ethanol is expected to grow because of the growth in flexible fuel vehicles. Brazil's largest buyer of sugarcane ethanol is currently the United States.
The United States produced 3.9 billion gallons of ethanol in 2005, up from 3.4 billion gallons in 2004. (Hira 6929) Currently, corn is the primary feedstock being used in the production process. In 2005, Brazil, produced 4.2 billion gallons of ethanol, up from 4.0 billion gallons in 2004. (Hira 6929) Production of ethanol in Brazil utilizes sugar and molasses from sugarcane as a primary raw material and therefore shows the technical feasibility of sugar-to-ethanol production. Corn-based ethanol makes up for almost 97 percent of the total ethanol manufactured in the United States. With gasoline prices high and corn production capacity limited, sugarcane ethanol imports become a better option. Also, sugarcane based ethanol is a better alternative than corn based ethanol because of the greater efficiency of sugarcane, the economic cost and the reduced environmental impact.
The first factor to consider is the efficiency of each of the options. Corn as a feedstock is considerably less efficient than other feedstock such as sugarcane. Pimentel estimates corn uses 29% more fossil fuels than the energy it produces and huge expansions in crop land and/or productivity would be needed in order to meet just a portion of United States vehicle needs for fuel. (65) Sugarcane is the most efficient feedstock for bio-fuels, because it is priced on a competitive basis with petroleum and does not negatively impact food prices like corn does. In Brazil, sugarcane based ethanol has the opportunity for huge expansion with minimal or no impact on food production. "There are more countries that could supply sugarcane ethanol and strong evidence for demand of ethanol in countries with limited sugarcane production capacity." (Hira 6927)
There are some differences in processing for corn versus the processing of sugarcane. When processing corn, the cornstarch must be extracted and turned into sugar before it can be used as a feedstock. Both sugarcane and corn must be grown in different manners and as a result, yield different amounts of raw material per acre. Because of this and the conditions required in the climates where they grow, sugarcane and corn ethanol have a different level of energy surplus. This energy surplus, which can be explained as the amount of energy used in production minus the energy that is generated, is important because of the steps needed to grow, harvest, refine and then produce the end product. Because the fuel product is similar, the most important difference between corn and sugarcane ethanol is the energy surplus.
A Natural Resources Research study conducted in 2005 showed that corn ethanol used up to "29 percent more energy than it produced." (Pimentel 65) Another study, published in Proceedings of the National Academy of Sciences in 2006, found that "corn ethanol yielded 25 percent more energy than the energy used to produce it." (Hill 11206) The study concluded that "corn ethanol produces 1.3 times more energy than it consumes, while sugarcane ethanol produces eight times as much energy as it consumes during production." (Hill 11206) Analysts have criticized corn ethanol because of it has an negative energy surplus and also because of the amount of acreage it needs. Additionally, the Proceedings of the National Academy of Sciences study notes that "dedicating all of U.S. corn production to corn ethanol would replace 12 percent of United States gasoline consumption." (Hill 11206)
The energy content of sugarcane is divided into three comparable parts. One-third is found in the sucrose component of sugarcane which is then changed to ethanol. One-third of the energy is in the sugarcane waste that is not removed from the land. The remaining third is bagasse which is what is left over after the sugarcane is pressed. The bagasse is burned as a way of providing energy to the ethanol facility. (Hofstrand 2009) Corn by products left over from processing go into feed. Sugarcane processing by-products do not have much value, but are instead used for heat and electricity as well as energy to power the processing plants. (Gallagher 115)
Sugarcane requires less energy for production than corn because it is harvested by hand and only replanted every six years. Before ethanol was introduced, the global sugar market was already in place, and Brazil was the world's largest sugarcane producer. When ethanol was first introduced, the changeover to sugarcane ethanol was not difficult because there was a good climate, plentiful land and cheap labor. In addition, demand and public policies were supportive. Repeated improvements in production have evolved sugarcane into a large and profitable crop. 55 percent of the sugarcane being produced in Brazil was used for ethanol production in 2010. The distribution of how much sugarcane goes to ethanol and how much is left over for sugar production is determined by manufacturer. The distribution is based on expected sugar, ethanol prices and demand. There are 430 plants that convert sugarcane into ethanol in Brazil, production that has doubled in the last 10 years. 27 billion liters or 7 billion gallons of ethanol was produced in Brazil in 2010. (Gallagher 120) By 2008, Brazil was exporting 19 percent of its production. Brazil has been exporting up to 20% of its sugarcane ethanol production for the last five years as of 2010. Sugarcane ethanol decidedly has a better energy balance than corn. Some critics are concerned the industry might contribute to deforestation in Brazil by clearing rainforest for sugarcane plantations. Regardless of the possible environmental issues raised in the production process, sugarcane is still more efficient than production from corn. The prices of sugarcane ethanol and corn ethanol depend on supply and demand factors in both the United States and Brazil as well as on bio-fuel policies in each country. Supply factors include, production costs, exchange rates and raw material prices. Demand factors include bio-fuel mandates, gasoline prices and flexible fuel vehicle popularity.
The cost of production for sugarcane ethanol is made up of raw materials, refining costs, and transportation costs from Brazil to the United States. Brazilian sugarcane is grown over a six year cycle. For the time period from 2006 to 2008, on average, the cost of production for sugarcane ethanol in Brazil was 24% lower than corn ethanol in the United States. (Crager 7404) Advantages over the competition can be made by achieving lower raw material costs, having better efficiency in processing and lastly, favorable exchange rates. (Gallagher 114) Food and bio-fuel markets are infinitely tied to one another. The cost of bio-fuels as an alternative to petroleum depend on the feedstock, corn or sugarcane, what country they are produced in, and the supply and demand growth of petroleum in general. (Hira 6925) Depending on the weather, the processing of the raw material and land quality, sugarcane is the cheapest bio-fuel. (Hira 6926) Costs of for corn ethanol in the U.S. $546 is per ton, while sugarcane in Brazil can cost $387 per ton. (Hira 6926)
The last factor to consider is the impact on the environment of each alternative. Developing crops for fuel requires a substantial amount of land and resources. In many cases, the land and resources might already be dedicated to food production. Current interest in ethanol fuel in the United States mainly lies in bio-ethanol, produced from corn, but there have been many discussions about how useful bio-ethanol will be in replacing gasoline in vehicles. Concerns relate to the large amount of land needed for crops, as well as the energy and pollution generated throughout the whole cycle of ethanol production.
Hira states that sugarcane fuel can have up to a 90% reduction in carbon dioxide emissions while corn ethanol leads to only 20-25% reduction. In 2009 80% of cars in Brazil where flex fuel. (6926) Brazil's 30-year-old ethanol fuel program uses cheap sugarcane, mainly bagasse for process heat and power, plus 100% ethanol for four million cars. Brazil gets more than 30% of its automobile fuels from sugarcane based ethanol.
The capability of the United States to increase its total amount of land for corn crops would mean reducing the amount of land used to grow other crops for food. (Crago, et al.7404) In contrast, presently, Brazil uses 1.6% of its total cropland and pasture land, with sugarcane ethanol production accounting for only 5%. (Crago, et al.7404) This means that food production would not be compromised if cropland was allowed to grow to accommodate the growing expansion of sugarcane production. (Crago, et al.7404) Crago, et al. concludes that because it is feasible to get 45% more sugarcane ethanol per land unit that corn ethanol, sugarcane ethanol is more efficient in it use of land. (7404) To replace all gasoline with ethanol from corn, the United States would need almost 350 million acres of dedicated corn. This does not include any corn for humans or animal feed. All the present United States area cultivated with corn comprises only 75 million acres. Currently, the U.S. needs almost 400 000 barrels/day of ethanol but produces only 300 000+ barrels/day.
Processing corn and sugarcane is very different. Processing of sugarcane provides all of the electrical and mechanical energy needed from burning the bagasse with even a surplus at least 10% that can be sold back to the government. Corn requires another source such as oil or natural gas to process it's energy needs in the refinery. Ethanol yield (gallons/acre) for sugarcane under good growing conditions is twice that for corn. For all these reasons, sugarcane ethanol is seven times more energy efficient. The use of sugarcane bagasse for fuel in the production of ethanol and eliminating gasoline by using ethanol removes the emission of 2.6 tons of CO2. (Goldemberg 2096) Sugarcane ethanol is a suitable replacement for gasoline because photosynthesis that occurs with the growing of the sugarcane during the next season reabsorbs the carbon dioxide. Another factor lowering the cost of producing sugarcane ethanol in Brazil is the availability of feedstock through much of the year. In Brazil, sugarcane ethanol plants operate nine months out of the year as the climate permits harvesting over several months.
There are three important differences when comparing the use of sugarcane or corn in the production of ethanol. First of all, the efficiency of sugarcane over corn is apparent in several factors. Sugarcane can be converted directly into ethanol while corn has to be converted into sugar then ethanol. Sugarcane is planted every six years which produces five harvests, then replanted. Corn is only planted yearly and harvest once each year. Sugarcane produces about 35 tons per harvested acre while corn on yields 8.4 tons per harvested acre. An acre of sugarcane results in about 560 gallons of ethanol while corn only produces about 420. (Hofstrand 2009)
Another difference proving that ethanol is a better option than using corn in ethanol is the cost of production. Not only is sugarcane cheaper to grow than corn per gallon of ethanol, but it can also be refined and produced at a lower cost. In addition, the by-product of harvesting corn can only be used for feed and the mills must use gas or coal to fuel production of the ethanol. Meanwhile, the unused waste from sugarcane is used to produce energy to power the processing mills, reducing the cost of energy needed to run the plants.
The last factor to consider in comparing ethanol to corn is the environmental impacts of each alternative. Currently, about nine million acres of land are used for sugarcane growing and about 28 million acres for corn. There is concern that expansion of corn cropland will be at the expense of other food crops while there is huge potential in Brazil to expand sugarcane acreage without damaging the acreage of other food crops. There is also significant evidence that production of sugarcane ethanol results in much less carbon dioxide emissions than corn. Therefore, the air and water quality issues for corn ethanol production raise some serious environmental concerns.
