William "Chops" Westfield mac.com> writes: > On Dec 29, 2006, at 11:58 AM, Stephen R Phillips wrote: > > > Bio Fuels are merely a drop in the bucket in terms of energy. > > They are not very efficient in terms of yield. Only thing > > I can think of is farmers can remain solvent with the idea. > > Yeah, it probably works out that the bio-fuel interest is actually > farming special interests having their way, and the hydrogen stuff > is the big natural gas producers hedging their bets (sources of About alcohol: 1) Traditional alcohol production uses wood as fire source. Not even that is needed if vacuum distillation is employed. Vacuum distillation is very energy effective (due to the use of low temperature heat sources, like sun or waste heat from fruit canning lines) and has a yield equal or higher to that of boil distillation. Also there are no hot vapors to explode outside the process, and no fire to ignite them. Note that this process requires more BTU than the normal distillation (huh?) but at a much lower temperature. Then there is adsorbtion. Freeze concentration is also an option (use the winter Luke). See more here: http://www.ces.purdue.edu/extmedia/AE/AE-117.html 1a) Heat consumption for production vs. heat of combustion is about 3x10^7J vs 1.4x10^8J. 2) Normal yield is 10+% alcohol by volume of fermented substance (no exotics here, apples, prunes, etc rejects from the market). With the same under continuous vacuum extraction the alcohol never reaches 14% in solution (which kills off the yeasts) so the yield is even higher. The yeasts do not mind the vacuum above, however it will froth 10 times more than normal. 3) Moonshine stills are NOT the way to produce alcohol. They make alcoholic beverages etc. Also we are in the 21nd century, not the 15th. 4) Rocket fuel is not anhydrous alcohol. V2 rockets used 75% ethyl alcohol + 25% water at a chamber pressure of 15 atm (with LOX oxydizer). They went up 180+km. Using a higher proportion of alcohol can melt things and degenerate into detontion mode. Current requirements for anhydrous alcohol for fuel are due to the mixing with gasoline for E85 etc. Water in E85 causes the alcohol to separate out. Thus 'real' alcohol fuel that permits 15:1 compression ratio is not anhydrous (and is also cheaper than anhydrous alcohol and easier to store). I think that the powers that be are more concerned about their tax revenue than about other things (like untaxed inebriation) when they manipulate information about alcohol in the media. Anyway alcohol is not snake oil. It will not solve all the problems, but it is one of the smaller problems. And unlike hydrogen it is not really really dangerous or hard to handle. Peter P. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist