English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

2007-03-12 11:22:48 · 4 answers · asked by kohlirosy 1 in Science & Mathematics Chemistry

4 answers

To reduce gasoline consumption..

2007-03-12 11:25:06 · answer #1 · answered by Anonymous · 1 1

Because they grow a lot of sugarcane and that can be converted to ethanol efficiently and they dont have to pay for oil.

Because sugarcane grows so fast in Brazil they can make it into fuel ethanol cheaper than buying crude oil to make gasoline.

Since the Ethanol is from a plant that just grew taking CO2 out of the air, using ethanol for fuel takes as much CO2 out of the air as it puts back when it is used so it is good for global warming as well.

The ethanol powers the car just like gasoline (if minor modifications have been made to the car's engine).

2007-03-12 18:45:56 · answer #2 · answered by Dr Fred 3 · 0 0

Ethanol can be produced from plants, so the need for oil is reduced. This is the coming thing, so get ready for it. This will reduce our need to keep OPEC happy. Maybe someday we can tell the camel jocks to "kiss our gas hole".

2007-03-12 18:26:51 · answer #3 · answered by Dino4747 5 · 1 1

Ethanol fuel in Brazil
From Wikipedia, the free encyclopedia
Jump to: navigation, search

Gasoline on the left, alcohol on the right at a filling station in BrazilIn Brazil, ethanol fuel is produced from sugar cane which is a more efficient source of fermentable carbohydrates than corn as well as much easier to grow and process. Brazil has the tropical climate that is required for the productive culture of sugarcane. Brazil has the largest sugar cane crop in the world, and is the largest producer of ethanol in the world. High government sales taxes on gasoline, as well as government subsidies for ethanol, have cultivated a profitable national ethanol industry. Nearly all fueling stations in Brazil offer a choice of either gasoline type C or hydrated ethanol.

Contents [hide]
1 The National Program for Alcohol
2 Electricity from bagasse
3 Program statistics
4 Effect on oil consumption
5 Environmental effects
6 Social implications
7 Exports of Brazilian ethanol
8 References
9 External links



[edit] The National Program for Alcohol

An early poster, prior to flexi-fuel engines, promoting alcohol fuel warns Brazilians not to mix standard petrol with alcohol fuel, and not to use alcohol in unconverted enginesWith the 1973 oil crisis the Brazilian government, then run by the general Emílio Garrastazu Médici, 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. 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.


[edit] Electricity from bagasse

Sugar cane plant (Saccharum officinarum).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. This is small by today's standards, about one third the size of new plants. Finland's fifth nuclear plant currently under construction is for 1,600 MW. This plant's expected cost of electricity production is EUR 2.37 c/kWh which for Finland was cheaper than coal or natural gas at 2003 prices, not counting carbon emission costs or penalties for the carbon based fuels. http://www.world-nuclear.org/info/inf76.htm

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.


[edit] Program statistics
Except where noted, the following data apply to the 2003/2004 season.

land use: 45,000 km² in 2000
labour: 1 million jobs (50% farming, 50% processing)
sugarcane: 344 million metric tonnes (50% sugar, 50% alcohol)
sugar: 23 million tonnes (30% is exported)
ethanol: 14 million m³ (7.5 anhydrous, 6.5 hydrated; 2.4% is exported)
dry bagasse: 50 million tonnes
electricity: 1350 MW (1200 for self use, 150 sold to utilities) in 2001

The labour figures are industry estimates, and do not take into account the loss of jobs due to replacement of other crops by sugarcane


[edit] Effect on oil consumption
Most cars in Brazil run either on alcohol or on gasohol; only recently dual-fuel ("Flex Fuel") engines have become available. Gas stations sell both fuels. The market share of the two car types has varied a lot over the last decades, in response to fuel price changes. Ethanol-only cars were sold in Brazil in significant numbers between 1980 and 1995; between 1983 and 1988, they accounted for over 90% of the sales. 80% of the cars produced in Brazil in 2005 were dual-fuel, compared to only 17% in 2004.

Ethanol-fueled small planes for farm use have been developed by giant Embraer and by a small Brazilian firm (Aeroálcool), and are currently undergoing certification.

Domestic demand for alcohol grew between 1982 and 1998 from 11,000 to 33,000 cubic metres per day, and has remained roughly constant since then. In 1989 more than 90% of the production was used by ethanol-only cars; today that has reduced to about 40%, the remaining 60% being used with gasoline in gasohol-only cars. Both the total consumption 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)[1]. 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).


[edit] Environmental effects
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 also 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 and kill snakes. Therefore, in sugarcane-growing parts of the country, the smoke from burning fields turns the sky gray throughout the harvesting season. As winds carry the smoke into nearby towns, air pollution goes critical and respiratory problems soar. Thus, the air pollution which was removed from big cities was merely transferred to the rural areas (and multiplied). 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 such machines have a higher productivity than people.

Many nations have produced alcohol fuel with no destruction to the environment. Advancements in fertilizers and natural pesticides have eliminated the need to burn fields. With condensed agriculture, like hydroponics and greenhouses, less land is used to grow more crops.


[edit] Social implications
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.


[edit] Exports of Brazilian ethanol
On 19 December 2005, the government-based Petrobras announced a contract with the Japanese Nippon Alcohol Hanbai for the creation of a joint-venture based in Japan to import ethanol from Brazil. The company, Brazil-Japan Ethanol, will have as its main object the creation of an ethanol market in Japan.

The U.S., potentially the largest market for the Brazilian ethanol, currently imposes trade restrictions on Brazilian ethanol in order to encourage domestic ethanol production, most of which has so far been based on processing corn instead of sugar cane or soybeans, which is much less efficient. There is concern that to allowing the heavily subsidized Brazilian ethanol to enter the U.S. market without taxation will undercut the budding ethanol industry in the United States (see a letter from six Democratic Senators to President Bush at http://harkin.senate.gov/news.cfm?id=255348 ). Others argue that rather than impose trade restrictions on the import of the Brazilian product, that the U.S. should make subsidies of its own available to support its fledgling domestic producers.

Sweden also has a large import from Brazil due to its 5% use of ethanol in all of its fuels. [1]

2007-03-12 18:26:57 · answer #4 · answered by theARTSlover003 3 · 0 0

fedest.com, questions and answers