Will our government force us to use E85
#11
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Joined: Aug 2006
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You're wrong. If you were dealing with equally efficient engines, then you would be more right, but changing the compression ratio also changes how efficiently the engine extracts useful work from the available energy in the fuel.
It is not really feasible to build a commercial engine that is so much more efficient running on ethanol that it will get more mpg than an equivalent power gasoline engine; but the difference will be less than a straight comparison of btu/gallon would imply, and there are some interesting laboratory alcohol engines that approach diesel efficiency.
E85 will never be mandated as a marine fuel for the simple reason that if you get too much water in E85, then the gasoline will separate from the water and alcohol. Neet alcohol, with no added gasoline, is a better marine fuel, but still unlikely to ever be mandatory. If biodiesel produced from algae becomes economically and environmentally sustainable, then market forces may gradually result in a de facto shift of marine power to diesel, but it still won't be mandated. The total amount of fuel burned by high-performance boaters simply isn't very great when compared to the total of all transportation fuel usage, so there just won't be all that much pressure for mandated marine fuel changes. On the other hand, you may well see a carbon tax added to your fuel bill.
It is not really feasible to build a commercial engine that is so much more efficient running on ethanol that it will get more mpg than an equivalent power gasoline engine; but the difference will be less than a straight comparison of btu/gallon would imply, and there are some interesting laboratory alcohol engines that approach diesel efficiency.
E85 will never be mandated as a marine fuel for the simple reason that if you get too much water in E85, then the gasoline will separate from the water and alcohol. Neet alcohol, with no added gasoline, is a better marine fuel, but still unlikely to ever be mandatory. If biodiesel produced from algae becomes economically and environmentally sustainable, then market forces may gradually result in a de facto shift of marine power to diesel, but it still won't be mandated. The total amount of fuel burned by high-performance boaters simply isn't very great when compared to the total of all transportation fuel usage, so there just won't be all that much pressure for mandated marine fuel changes. On the other hand, you may well see a carbon tax added to your fuel bill.
#12
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Joined: May 2001
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From: Lake Lanier, GA
BTU/lb (energy Content) are based on the weight of the fuel, now you have to combine that with the amount of fuel being used (Air Fuel Ratio) to get your total BTU (Total Thermal Energy)
Here is some simple Chart that I had, I'll do the math on E85 later but it winds up between gasoline and methanol.
lbs of air (lbs) A/F Ratio Pounds of Fuel (lbs) Energy Content of Fuel (BTU/lb) Total Thermal Energy (BTU)
Gasoline 42.64, 12.8:1, 2.89, 18,500, 53,176
Methanol 42.64, 6.0:1, 7.11, 9,500, 67,545
Nitromethane 42.64, 1.7:1, 25.08, 5,000, 125,412
As you can see the fuels with lower energy content put out more total BTU's sinces the overall volume is that much more due to the Air Fuel Ratio...
Last edited by RumRunner; 02-23-2008 at 09:18 AM.
#13
Payton, Indy Cars were already running on Methanol, that is why consumption did not increase.
#14
Payton, Indy Cars were already running on Methanol, that is why consumption did not increase.
#15
all this sounds great but all i know is years ago when i was dragboat racing when we took a blowngas boat and changed it to run on methanol the first thing you had to do is double the fuel going in to the motor and go up on boost. yes power came up but if we had left the boost the same and nozzles the same we would have leaned out the motor.
#20
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