Sunday, November 15, 2009

Ethanol


I have always been fascinated by the fact that some cars are able to run on sugarcane and that it is as effective as petrol. Ever since I was told that most cars in Brazil used sugarcane as their fuel I have been interested to find out how it is possible. As well as the impacts it may have or may not have on the environment. I was also interested to see whether it may be the answer to a “greener” environment and potentially be the fuel answer to climate change. After having done some researched, I discovered the advantages and disadvantages of using ethanol as a fuel and how successful countries have been while using it as an alternative fuel. Lets take a look at what I found out.

What is ethanol and how is it made?

Ethanol is an alcohol -based fuel that is produced from the fermentation of natural resources such as; sugarcane and corn. Ethanol is mixed with gasoline to form a fuel with a higher octane rating and that releases fewer harmful emissions.

Ethanol is commonly made through the process of fermentation. The sugarcane is crushed and heated to form molasses or sucrose, which is dissolved by using water. From here the aqueous solution is fermented using yeast in temperatures between 20-35°C. This ethanol is about 15% and is diluted, in order to get 95% ethanol; it needs to go through a process of distillation where the water is removed. However in order to achieve a more concentrated substance of ethanol, a further process of molecular sieves is done. The final product is 99.9% ethanol.

There are other ways of producing ethanol using different methods, however fermentation is the most common and effective way.

Discuss the advantages and disadvantages of ethanol as an alternative car fuel.

Advantages

® Ethanol is a renewable source, it is made from sugarcane, and corn etc, these substances can be easily replaced in a significant amount of time.

® Improved emission levels – less carbon dioxide and soot released as by products.

® Less oxygen needed for combustion

® Reduces engine knock

® Biodegradable

® Carbon dioxide neutral, the carbon dioxide is said to be recycled as the plants use the carbon dioxide that has been released to photosynthesize.

Disadvantages

® Oxygenated = less energy per gram, more grams are needed for the energy to be as affective as normal petroleum.

® Increased aldehyde emissions

® Nitrogen oxides produced

® Uses vital resources – grain, land, water, it is said that food is being taken away from undeveloped countries which is contributing to famine.

® Can damage some vehicles if the engine has not been modified for the fuel.

® Energy requirements for production are high; a large amount of energy is needed during the production. Less energy is gained once the production is over.

® Non- competitive price without subsidies

® Expensive to produce compared to other fuels.

Evaluate the success of current usage of ethanol as an alternative fuel.

Brazil and the United States of America are the largest producers in the world. Brazil has one of the largest bio-ethanol programs and is said to be the only country that has a sustainable bio-fuel environment. This is due to the large amount of sugarcane being produced by farmers. 40% of the cars in Brazil use pure ethanol and the rest of the cars use 22% blend, with 78% being gasoline (E22). This large number of cars using the fuel is due to the ethanol fuel being the cheapest in the world. Brazil’s ethanol success was due to the large investment made by the government in infrastructure and research. 

The USA produces and consumes more ethanol fuel than any other country in the world. Cars in the United States are able to run on a blend of 10% ethanol. There are 1900 stations currently distributing ethanol fuel. The USA uses corn as their main source for the production of ethanol fuel.

Australia has a 10% cap on the concentration of fuel ethanol blends. The common fuel used is E10, which is 90% unleaded petrol and 10 % ethanol fuel. E10 is mostly available closer to the source of production, Queensland. Queensland in Australia’s major ethanol production state due to the large fields of sugarcane.

Countries around the world are becoming more and fonder of ethanol fuel and so production of ethanol around the world is increasing rapidly. This is due to the search for an alternative fuel to preserve non-renewable resources such as fossil fuels.

The graph shows the gallons produced per country.

 Assess the potential of ethanol as an alternative fuel.

Ethanol has the potential to be an ideal alternative fuel as the production includes the use of renewable resources instead of the non-renewable resources like fossil fuels. The carbon dioxide emissions are less and the plants, through photosynthesis, use the carbon dioxide released. 

This is shown in the diagram on the right. Countries are also able to produce their own fuel using corn or sugarcane and do not need to import fuels from foreign countries. Ethanol fuel is more environmentally friendly compared to other fuels and does not release as many harmful gases in the atmosphere.

 However there are also negatives for using ethanol as an alternative fuel. The downfall of using ethanol is that there needs to be a large amount of corn and sugarcane etc. grown in order to produce the fuel. This is a further problem, as a balance needs to be made between substances used for food and to produce ethanol. The production of ethanol requires a large amount of energy and is expensive compared to the production of other fuels. In order to use ethanol as a fuel, the engines of cars need to be modified and suited to use the fuel.

The production of ethanol fuel is becoming more popular amongst countries and the use of ethanol in the countries depends on the government’s thoughts towards the fuel. However the potential of using ethanol is increasing as the technology advances.

References

"What Countries Are the Main Ethanol Producers?" WiseGEEK: clear answers for common questions. Web. 10 Nov. 2009. http://www.wisegeek.com/what-countries-are-the-main-ethanol-producers.htm 

"What is ethanol? - www.drive.com.au." Used Cars & New Cars for Sale | Car Sales & Car Reviews - Drive.com.au. Web. 10 Nov. 2009. http://www.drive.com.au/Editorial/ArticleDetail.aspx?ArticleID=59638

"Sugarcane ethanol: Brazil's biofuel success -." SciDev.Net. Web. 11 Nov. 2009.http://www.scidev.net/en/features/sugarcane-ethanol-brazils-biofuel

success.html

"E85 | What is Ethanol?" E85 | Ethanol Gasoline Blend. Web. 11 Nov. 2009.http://e85.whipnet.net/what.is.ethanol/index.html

Digital image. Web. http://www1.eere.energy.gov/vehiclesandfuels/images/facts/fotw447.gif

Digital image. Web. http://www.ewb.monashclubs.org/images_content/FormtoFuel.gif




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