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| quote: | Originally posted by colonelcrisp
If you look at the potential chemical energy contained in one metric tonne of corn vs the potential chemical energy contained in one metric tonne of sweet crude, it doesn't take much to realize which is more efficient. not to mention in the case of ethanol, the production process is highly energy consuming. biodiesel is a different process but still requires alot of energy to produce. Oil refining on the other hand isn't much better on the energy consumption, but when you look at the chemical energy your producing in teh byproducts of fractional distillation, it far outweighs the energy input.
Biodiesel production - you get biodiesel, of the two popular fossil fuel substitutes, biodiesel is the most efficient, but it still requires 27% more energy to produce than you get out of it. source
Ethanol production - you get ethanol (natives jump for joy), and you get corn mash which can be in turn blended with sileage and fed to cattle. It is also the Least efficient alternative as if you take into account the energy required to farm and harvest the corn, you put more energy in than you get out of it. source
Crude oil - you get kerosene (naptha), gasoline, diesel oil, asphalt, and a host of complex hydrocarbon chains which are further processed into PVC, ABS plastics, etc etc |
This is why I propose using algae oil as a biofuel. This gets rid of the energy problem you mentioned earlier. Look how much algae oil can be produced vs. other crops:
Sources: http://www.algaefuel.org
http://oakhavenpc.org/cultivating_algae.htm
In addition, the National Renewable Energy Laboratory within the Department of Energy states that:
"Under optimum growing conditions micro-algae will produce up to 4 lbs./sq. ft./year or 15,000 gallons of oil/acre/year [I know the graph I posted above says 10,000 but it is around that ballpark]. Micro-algae are the fastest growing photosynthesizing organisms. They can complete an entire growing cycle every few days." Sustainability is not an issue.
Also algae are low input-high energy yield source producing 30 times more energy per acre than feedstock land (aka ethanol from food crops such as corn)
Source: http://www.washingtonpost.com/wp-dy...8010303907.html
Another benefit to using algae oil is that we don't have to deprive farmers of their corn crop anymore. "According to a U.N. expert....Jean Ziegler, the United Nations special reporter on the right to food and sociology professor at the University of Geneva and the University of the Sorbonne in Paris....he stated that blame for the record high price of some staple grain crops is directly attributable to biofuel initiatives.
"This much is factually accurate it appears. Between September 2006 and November 2006 corn prices rose 55 percent. Corn prices are at record highs of over $3 USD per bushel. The Wall Street Journal says this is largely due to the new industrial demand for corn for ethanol conversion. This has caused food producers such as Tyson to struggle."
All in all poor people have more to eat around the world and famers get to keep a roof over their heads which is mainly what this thread was originally about.
Source: http://www.dailytech.com/Biofuels+S...article9436.htm
Last but not least is that algae fuel are biodegradable so if it leaks into the ground or atmosphere it will do no harm to the environment. In fact another way they are beneficial is that they suck up CO2. This is why the best to place algae bioreactors are next to the top source of CO2 and that would be fossil fuel based power plants such as coal.
The only problem here is not energy efficiency because as I noted above algae yields a high energy output, but rather the cost to run this type of technology. I think these guys said it best:
"The biggest challenge is cutting the cost of production, which by one Defense Department estimate is running more than $20 a gallon.
“If you can get algae oils down below $2 a gallon, then you’ll be where you need to be,” said Jennifer Holmgren, director of the renewable fuels unit of UOP, an energy subsidiary of Honeywell International. “And there’s a lot of people who think you can.”
Source: http://www.nytimes.com/2007/12/02/u...r=1&oref=slogin
I believe in that last sentence. There are a lot of people including me who await a cost effective technology to come to fruition.
A cool fact. If you exclude the cost of biofuel production, "according to Michael Briggs: “The operating costs, including power consumption, labor, chemicals, and fixed capital costs (taxes, maintenance, insurance, depreciation, and return on investment) worked out to $12,000 per hectare. That would equate to $46.2 billion per year for all the algae farms, to yield all the oil feedstock necessary for the entire country. Compare that to the $100 - $150 billion the U.S. spends each year just on purchasing crude oil from foreign countries, with all of that money leaving the US economy.” Scientists at NREL think that these new fuels will become competitive by 2010."
Source: http://www.greenfuelonline.com/gf_files/algaefuel.pdf
Conclusion: What have we learned?
-Algae type of biofuels are sustainable and yield a high energy output.
-Algae can displace corn as a biofuel and poor people can eat again!
-Reduce greenhouse emissions, particularly CO2
-Reduce, if not, eliminate our dependence on foreign oil and maybe terrorism in the Middle East. (<---think about that one)
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