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Ethanol fuel in Brazil
Brazil’s 29-year-old ethanol fuel program uses cheap sugar cane, mainly bagasse (cane-waste) for process heat and power, and modern equipment, and provides a ~22% ethanol blend used nationwide, plus 100% hydrous ethanol for four million cars. The Brazilian ethanol program provided nearly 700,000 jobs in 2003, and cut 1975–2002 oil imports by a cumulative undiscounted total of US$50 billion. Today, Brazil gets more than 30% of its automobile fuels from sugar cane-based ethanol.
The Brazilian government provided three important initial drivers for the ethanol industry: guaranteed purchases by the state-owned oil company Petrobras, low-interest loans for agro-industrial ethanol firms, and fixed gasoline and ethanol prices where hydrous ethanol sold for 59% of the government-set gasoline price at the pump. These pump-primers have made ethanol production competitive yet unsubsidized.
In recent years, the Brazilian untaxed retail price of hydrous ethanol has been lower than that of gasoline per gallon. Approximately US$50 million has recently been allocated for research and projects focused on advancing the obtention of ethanol from sugarcane in São Paulo.
Additional recommended knowledge
The National Program for Alcohol
With the 1973 oil crisis, the Brazilian government, then run by the general Ernesto Geisel, initiated in 1975 the Pró-Álcool program.
The Pró-Álcool or Programa Nacional do Álcool (National Alcohol Program) was a nation-wide program financed by the government to phase out all automobile fuels derived from fossil fuels (such as gasoline) in favour of ethanol. It began with the anhydrous alcohol to blend with the gasoline. This mixture has been used since then and is now done with 24% of alcohol and 76% gasoline (commonly known as gasohol). The program successfully reduced by 10 million the number of cars running on gasoline in Brazil, thereby reducing the country's dependence on oil imports. The decision to produce ethanol from fermented sugarcane was based on the low cost of sugar at the time. Other sources of fermentable carbohydrates were tested such as the manioc.
Electricity from bagasse
Sucrose accounts for little more than 30% of the chemical energy stored in the mature plant; 35% is in the leaves and stem tips, which are left in the fields during harvest, and 35% are in the fibrous material (bagasse) left over from pressing.
Part of the bagasse is currently burned at the mill to provide heat for distillation and electricity to run the machinery. This allows ethanol plants to be energetically self-sufficient and even sell surplus electricity to utilities; current production is 600 MW for self-use and 100 MW for sale. This secondary activity is expected to boom now that utilities have been induced to pay "fair price "(about US$10/GJ or US$0.036/kWh) for 10 year contracts. This is approximately half of what the World Bank considers the reference price for investing in similar projects (see below). The energy is especially valuable to utilities because it is produced mainly in the dry season when hydroelectric dams are running low. Estimates of potential power generation from bagasse range from 1,000 to 9,000 MW, depending on technology. Higher estimates assume gasification of biomass, replacement of current low-pressure steam boilers and turbines by high-pressure ones, and use of harvest trash currently left behind in the fields. For comparison, Brazil's Angra I nuclear plant generates 657 MW.
Presently, it is economically viable to extract about 288 MJ of electricity from the residues of one tonne of sugarcane, of which about 180 MJ are used in the plant itself. Thus a medium-size distillery processing 1 million tonnes of sugarcane per year could sell about 5 MW of surplus electricity. At current prices, it would earn US$ 18 million from sugar and ethanol sales, and about US$ 1 million from surplus electricity sales. With advanced boiler and turbine technology, the electricity yield could be increased to 648 MJ per tonne of sugarcane, but current electricity prices do not justify the necessary investment. (According to one report, the World bank would only finance investments in bagasse power generation if the price were at least US$19/GJ or US$0.068/kWh.)
Bagasse burning is environmentally friendly compared to other fuels like oil and coal. Its ash content is only 2.5% (against 30-50% of coal), and it contains no sulfur. Since it burns at relatively low temperatures, it produces little nitrous oxides. Moreover, bagasse is being sold for use as a fuel (replacing heavy fuel oil) in various industries, including citrus juice concentrate, vegetable oil, ceramics, and tyre recycling. The state of São Paulo alone used 2 million tonnes, saving about US$ 35 million in fuel oil imports.
Researchers working with cellulosic ethanol are trying to make the extraction of ethanol from sugarcane bagasse and other plants viable on an industrial scale.
Except where noted, the following data apply to the 2003/2004 season.
The labour figures are industry estimates, and do not take into account the loss of jobs due to replacement of other crops by sugarcane
Effect on oil consumption
Most cars in Brazil run either on alcohol or on gasohol; only recently dual-fuel ("Flex-Fuel") of ethanol and the ethanol/gasohol ratio are expected to increase again with deployment of dual-fuel cars.
Presently the use of ethanol as fuel by Brazilian cars - as pure ethanol and in gasohol - replaces gasoline at the rate of about 27,000 cubic metres per day, or about 40% of the fuel that would be needed to run the fleet on gasoline alone. However, the effect on the country's overall oil use was much smaller than that: domestic oil consumption still far outweighs ethanol consumption (in 2005, Brazil consumed 2,000,000 barrels of oil per day, versus 280,000 barrels of ethanol). Although Brazil is a major oil producer and now exports gasoline (19,000 m³/day), it still must import oil because of internal demand for other oil byproducts, chiefly diesel fuel (which cannot be easily replaced by ethanol).
According to government statistics Brazil produced 17.471 billion litres of ethanol in 2006. For 2007 Wagner Rossi, president of Companhia Nacional de Abastecimento, expects a production growth of 21.9%, bringing the total ethanol production to 21.298 billion litres.
Comparison with the United States
Brazil's sugar cane-based industry is far more efficient than the U.S. maize-based industry. Brazilian distillers are able to produce ethanol for 22 cents per liter, compared with the 30 cents per liter for corn-based ethanol. Sugarcane cultivation requires a tropical or subtropical climate, with a minimum of 600 mm (24 in) of annual rainfall. Sugarcane is one of the most efficient photosynthesizers in the plant kingdom, able to convert up to 2% of incident solar energy into biomass. Ethanol is produced by yeast fermentation of the sugar extracted from sugar cane. Sugarcane production in the United States occurs in Florida, Louisiana, Hawaii, and Texas. In prime growing regions, such as Hawaii, sugarcane can produce 20 kg for each square meter exposed to the sun.
U.S. corn-derived ethanol costs 30% more because the corn starch must first be converted to sugar before being distilled into alcohol. Unfortunately, despite this cost differential in production, in contrast to Japan and Sweden, the U.S. does not import Brazilian ethanol because of strict U.S. trade barriers (tariffs) corresponding to a levy of a 54-cent per gallon. These are promoted by the powerful American sugar lobby, which does not want a competitor to high-fructose corn syrup, and domestic sugar interests. The United States and Brazil lead the industrial world in global ethanol production. On March 9, 2007 Ethanol diplomacy was the focus of President Bush's Latin American tour, in which he and Brazil's president, Luiz Inacio Lula da Silva, agreed to share technology. The Brazilian sugar cane trade agreements permit various Central American (Colombia, Costa Rica, and Panama), Caribbean, and various Andean Countries tarrif-free trade thanks to concessionary trade agreements.
The improvement in air quality in big cities in the 1980s, following the widespread use of ethanol as car fuel, was widely evident; as was the degradation that followed the partial return to gasoline in the 1990s.
However, the ethanol program was not perfect and brought a host of environmental and social problems of its own. Sugarcane fields were traditionally burned just before harvest, in order to remove the leaves, kill any snakes and fertilize the fields with ash. The smoke produced each season produces the same amount of carbon pollution as the sugarcane would have produced if it were left in the field to rot, which is relatively little. However, the smoke greatly impacts the sugarcane-growing parts of the country, turning the sky gray and air hazardous throughout the harvesting season. As winds carry the smoke into nearby towns, air pollution goes critical and respiratory problems soar. This practice has been decreasing of late, due to pressure from the public and health authorities. In Brazil, a recent law has been created in order to ban the burning of sugarcane fields, and machines will replace human labor as the means of harvesting cane. This not only solves the problem of pollution from burning fields, but new machines also have a higher productivity than people.
Many nations have produced alcohol fuel with limited destruction to the environment. Advancements in fertilizers and natural pesticides have all but eliminated the need to burn fields, however chemical pollution from runoff may turn out to be just as harmful to the environment as the smoke. To ensure long-term viability for Brazil’s ethanol fuel industry, growers must be focused on sustainability rather than short-term productivity.
Since sugarcane only requires hand labor at harvest time, this shift also created a large population of destitute migrant workers who can only find temporary employment as cane cutters (at about US$3 to 5 per day) for one or two months every year. This huge social problem has contributed to political unrest and violence in rural areas, which are now plagued by recurrent farm invasions, vandalism, armed confrontations, and assassinations.
Some question the viabiliy of biofuels like ethanol as total replacements for gasoline/crude oil. One concern is that sugarcane cultivation will displace other crops, thus causing food shortages. However, these concerns seem to be groundless. Despite having the world's largest sugarcane crop, the 45,000 km² Brazil currently devotes to sugarcane production amount to only about one-half of one percent of its total land area of some 8.5 million km². In addition, the country has more unused potential cropland than any other nation. Some commentators, like George Monbiot, fear that the marketplace will convert crops to fuel for the rich, while the poor starve and biofuels cause environmental problems. It is unclear how this would be different from the current situation, as most food crops are grown and exported to richer nations, and neglects the very real environmental problems that the burning of fossil fuels causes. The cultivation of sugarcane for energy production is only likely to increase as fossil fuels become increasingly scarce and more expensive.
Exports of Brazilian ethanol
|This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Ethanol_fuel_in_Brazil". A list of authors is available in Wikipedia.|