Sugarcane ethanol
Sugarcane ethanol is a biofuel made from the fermentation of sugars extracted from sugarcane. It is primarily used as a transportation fuel, either in its pure form or blended with gasoline. Brazil stands out as the largest producer of sugarcane ethanol, leveraging its agricultural advantages and government support to establish a successful industry. In recent years, the increasing volatility of crude oil prices has heightened interest in this alternative fuel, particularly among oil-importing nations seeking to diversify their energy sources and reduce reliance on foreign oil.
The production of sugarcane ethanol is praised for its potential environmental benefits, including lower greenhouse gas emissions compared to traditional gasoline. Moreover, it offers socio-economic advantages by creating jobs in rural areas involved in its production and distribution. However, the viability of sugarcane ethanol is contingent upon government policies and support, particularly to manage the balance between food supply and biofuel production, which can lead to food price increases and biodiversity loss. While Brazil's success offers insights, replicating its model in other developing countries may require sustained governmental backing and careful management of agricultural practices to ensure sustainability.
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Sugarcane ethanol
Summary: Ethanol can be made by the fermentation of sugars produced by sugarcane. It is used primarily as a transport fuel, either in pure form or as a gasoline additive. Brazil, the world’s largest ethanol producer, commonly makes ethanol from sugarcane.
The interest in sugarcane-based ethanol was reinforced at the beginning of the 21st century by the increasing volatility and rapid surge in crude oil prices. The high dependence of the majority of the world’s developed and developing countries on a handful of oil and gas producers in Middle East and West Asia, plagued by spare capacity concerns and geopolitical tensions, has made it almost inevitable that these dependent nations must diversify their energy resources. Ethanol from sugarcane provides an attractive alternative, with its potential technical, social, economic, and environmental benefits as compared to gasoline and ethanol produced from other sources. However, its commercial viability and competitiveness is largely dependent on prolonged government nurturing and support of the sugarcane industry. Furthermore, large-scale production of ethanol from sugarcane may trigger a food-fuel trade-off, leading to increased food prices loss of biodiversity as scarce land resources become increasingly dedicated to biofuel-producing sugarcane crops.
The interest in sugarcane-based ethanol as an alternative fuel for transport, especially in oil-importing developing nations, is motivated by the need to diversify energy sources and lower exposure to the price volatility of the international oil market. Sugarcane-based ethanol is especially attractive for the heavy oil-importing countries (for instance, landlocked countries) that pay high prices for delivered petroleum but already have a comparative advantage in production of sugarcane. Furthermore, production of ethanol from sugarcane holds the promise of contributing to rural development by creating jobs in production, manufacture, transport, and distribution of feedstock and products.
In 2023, Brazil used pure sugarcane-based ethanol in about 20 percent of its vehicles; in the rest of the nation’s vehicles, it used at least 25 percent ethanol blend. Some developing countries, including China, used 10 percent ethanol blend; India mandated a 5 percent ethanol blend. Brazil’s National Alcohol Program (PROALCOOL) started as a response to the Middle East oil embargo of 1973. At that time, Brazil’s dependence on foreign oil made it even more vulnerable than the United States. Brazil’s program has been extremely successful, although its development has not come without hitches. The feedstock costs account for 58 to 65 percent of the cost of ethanol production in Brazil. Thus, commercial viability of ethanol is critically dependent on the cost of cane production. However, the center-south region of Brazil has no parallel in terms of productivity, and the ethanol produced in the region is the cheapest in the world. This could be attributed to the country’s rain-fed cane cultivation, availability of large amounts of unused land, constant support through decades of research, and commercial cultivation.
Furthermore, most distilleries in Brazil belong to sugar mill/distillery complexes that are capable of changing the production ratio of sugar to ethanol. This capability enables plant owners to take full advantage of fluctuations in the relative prices of sugar and ethanol, as well as benefit from the much higher price that can be fetched by converting molasses into ethanol. Besides, flex-fuel vehicles, which were introduced in Brazil in 2003, have further increased the attractiveness of building hybrid sugar-ethanol complexes. In 2020, more than 84 percent of all motor vehicles produced in Brazil are now flex-fuel: able to run on any mixture of alcohol and gasoline, as well as on 100 percent alcohol. These engines can also operate with regular gasoline alone if there is a shortage of biofuels.
Moreover, ethanol in Brazil provides significant reductions in greenhouse gas (GHG) emissions compared to those from gasoline, a result of the relatively energy-efficient nature of sugarcane production, the use of bagasse (left over after the juice has been squeezed out of sugarcane stalks) as process energy, and the advanced state of sugar farming and processing. Thus, the savings in net energy value or balance (that is, the difference between the energy in the fuel product, or output energy, and the energy needed to produce the product, or input energy) and associated GHG emissions from blending of sugarcane-based ethanol with gasoline, on a life-cycle basis, may turn out to be much greater than ethanol produced from other sources, such as corn.
However, in order to ensure that ethanol is produced from sugarcane in a sustainable manner and enhances savings in net energy value and GHG emissions, ethanol plants should be produced using biomass and not fossil fuels; cultivation of annual feedstock crops should be avoided on land rich in carbon (above- and belowground), such as peat soils used as permanent grassland; by-products should be utilized efficiently in order to maximize their energy and GHG benefits; nitrous oxide emissions should be kept to a minimum by means of efficient fertilization strategies; and the commercial nitrogen fertilizer used for crops should be produced in plants that have facilities to mitigate the nitrous oxide gases generated during production.
A critical issue is whether Brazil’s success in achieving self-sufficiency and a commercially competitive sugarcane-based ethanol industry can be replicated elsewhere. In this context, it deserves to be mentioned that Brazil’s success was preceded by more than 20 years of government support. The country continues to maintain a significant tax differential between gasohol (80 percent gasoline and 20 percent ethanol) and hydrous ethanol. A large number of countries around the world are growing sugarcane, but none has been able to match Brazil’s sugarcane cost structure. Thus, continued support in the form of subsidies—indirect, direct, or both—may be needed to launch and maintain a sugarcane-based biofuels industry in most developing countries. Although a rapid surge in crude prices is expected to make ethanol production and consumption viable in the near future, governmental policy making will remain hinged to uncertainty and hence may lack adequate clarity with regard to the extent of support necessary to render a burgeoning ethanol industry self-sustaining.
Bibliography
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Energy Sector Management Assistance Program. “Potential for Biofuels for Transport in Developing Countries.” Report 312/05. Washington, DC: World Bank, 2005.
Gerdal, B. Hahn-Ha, M. Galbe, M. F. Gorwa-Grauslund, G. Liden, and G. Zacchi. “Bio-ethanol: The Fuel of Tomorrow From the Residues of Today.” Trends in Biotechnology 24 (2006).
Sloat, Linsey, et al. "The World Is Growing More Crops - But Not for Food." World Resources Institute, 20 Dec. 2022, www.wri.org/insights/crop-expansion-food-security-trends. Accessed 1 Aug. 2024.
Sorda, Giovanni, Martin Banse, and Claudia Kemfert. “An Overview of Biofuel Policies Across the World.” Energy Policy 38 (2010). Sousa, Dayanne, et al. "Brazil's Beloved Sugar-Cane Cars Are Slowing EV adoption." Bloomberg, 19 Jul. 2023, www.bloomberg.com/news/features/2023-07-19/why-brazil-is-falling-behind-in-the-electric-car-transition?embedded-checkout=true. Accessed 1 Aug. 2024.