ESL Lesson 1
Oil in Our Every Day Life
ESL Lesson 2
The History of Mining
ESL Lesson 3
Economic growth
ESL Lesson 4
Delivery Systems
ESL Lesson 5
Cities and Population Movement
ESL Lesson 6
Recycling
ESL Lesson 7
Rubber
ESL Lesson 8
Farming
Sugarcane Ethanol
Key questions on energy options
Is the energy source sustainable?
Sustainable, for reasons I outlined in this article.
What are the potential negative externalities (effects) of producing/using this
energy source?
Few potential negative externalities to my knowledge. I have heard mention (heard about) that expanded sugarcane production will be at the expense of rain forest, but the sugarcane plantations in Brazil are not near the rain forests. I do not know if rainforests in other tropical countries may be put in danger by expanded sugarcane production.
What is the EROEI?
The energy return on sugarcane ethanol appears to be in the (8:1) range, which would make it better than gasoline. More on that below.
Is it affordable?
It is affordable, but the U.S. punishes Brazilian ethanol with a $0.54/gallon tariff to protect its unsustainable corn ethanol production.
Are there better alternatives?
For a liquid fuel that will fit in the current transportation infrastructure, I don't think sugarcane ethanol can be beaten (find something better) with existing technology. But it can't provide our current level of energy usage.
Are there other special considerations?
The industry can provide an economic boost to tropical countries, where it is sorely needed.
In summary, are the advantages of the source large enough to justify any
negative consequences?
In my opinion, the advantages of sugarcane ethanol justify the costs, provided habitat (ecosystem/forest) is not being destroyed to grow more sugarcane.
I find it shameful that the U.S. subsidizes an unsustainable and polluting industry like grain ethanol, and punishes a sustainable industry like sugarcane ethanol. Farmers in the U.S. can grow sugarcane in some areas within the country, but the subsidies are for corn not sugarcane. Yet even with those tariffs in place, Brazil can still ship their ethanol to the U.S. and compete with homegrown corn ethanol prices.
The energy return on sugarcane ethanol as it has been calculated does appear to be in the (8:1) range, which would make it better than gasoline. On the face of it, this seems absurd. Nature has already done the major processing for fossil fuels, and turned ancient plant material into long-chain, energy dense compounds. In the case of sugarcane ethanol, a lot of energy inputs are required, especially for purifying the ethanol, but those inputs are being satisfied by burning the sugarcane ethanol residues (wastes) to produce process heat. Therefore, they are not being counted against the energy output.
However, gasoline accounting is not done in this manner (way). When oil is refined to liquid fuels, a lot of fuel gas is produced. That fuel gas tends to be burned in the refinery to produce process heat, but I have still charged that against the energy balance I calculated above. If I had done the energy accounting as is done with sugarcane ethanol, one could state that the energy return of gasoline is actually only the initial energy required to get the oil out of the ground, which averages about (17:1) worldwide. The refining step would get a free pass, since the energy in the oil is ultimately used to refine the oil. So no, the energy balance of sugarcane ethanol is not in fact better than that for gasoline.
Worlds' largest producer is Brazil which can produce at an EROEI between 8.3 and 10.2 More info at: http://i-r-squared.blogspot.com/2006/10/report-brazilian-ethanol-is.html
Continue to: Cellulosic Ethanol
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Rubber
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Bio-fuels and Ethanol
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Liquid Fossil Fuels
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Grain Ethanol
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Sugarcane Ethanol
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Cellulosic Ethanol
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Biodiesel
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Biomass Gasification
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Wind and Solar
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Conservation
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