Math math math -Kyle
On Thu, Oct 14, 2010 at 1:49 PM, Kurt Nolte <[email protected]>wrote: > Perhaps, but you ( not you personally, average driver you) won't > notice typically 5%. At 20mpg, 5% mileage drop is only 1mpg. Most > folks see a 1-2 mpg variance between tanks as a matter of course, > based on driving conditions and style. Most of the folks claiming to > see massive mileage drop from ethanol seem to claim an average of > 30mpg. 95% of 30mpg is still 28.5, a difference of 1.5mpg. > > On a 300 mile trip you're going to pump 10.52 gallons instead of 10.0 > for the 30mpg vehicle, 15.8 versus 15.0 for the 20mpg case. The number > of people who actually track their receipts and fuel purchases closely > enough to notice a half gallon variance is very small (I'm one of > them, as I'll notice a .1-.2 gallon difference for the same mileage). > Even lower are the number of people who go the same number of miles > between fills, which would be requisite for noticing a difference in > volume to be meaningful. > > A gallon of "standard" gasoline has 114000 BTUs in it. Industry > accepts a variation of 3% from this figure, so it can range between > 110580-117420BTUs per gallon for standard 87 octane regular unleaded. > Premium gasoline has app. 1% less energy than regular, by the way, > reflecting the increased amount of anti-knock additives. > > Ethanol has 76100 BTUs per gallon. This figure basically does not > change, as ethanol is a single chemical compound. No additives, no > extra volatiles, no nothing of the sort. Water content will change > this, granted, but then you're talking about EXX, not straight > ethanol. > > If we take a high-standard gallon of gasoline and make it into a > gallon of E10, we have .90*117420+.10*76100 = 113288, or 99.38% of the > energy of "standard" gasoline, or 102.44% of the lower acceptable > content limit. Similarly a low-standard gallon of E10 will have 93.97% > and 96.88% of standardized and low-limit gasoline respectively. > > This means that your two industry extremes are a .62-6.03% loss in > energy content per gallon with respect to "standard" gasoline, and you > aren't going to have any clue where in that spectrum your base stock > gasoline will fall. > > Hmmmm, yes, I can see where people are killing their wallets on E10. > > Add in the fact that folks have made ridiculously unscientific > statements like "I always see 8-10% drop on fuel I know has ethanol in > it" and you now /know/ that there's a bias to it. Proper data would be > blind, possibly even double-blind. > > I would have absolutely no issues with conducting a double-blind study > using anti-ethanol subjects to determine the real-world relative fuel > economy loss of E10 and E15 (and maybe E20) to E00. Only modification > I would make to the vehicles involved would be the addition of a fuel > cell, which would allow more accurate fuel volume readings. Allow a > third party (say, a local fuel distributor) to mix the fuel up and > simply label four containers A, B, C and D. Fuel the vehicles daily, > taking odometer readings each time, and allow them to be driven as > normal (minus fueling stops) for a period of say 2-4 weeks. To take > different driving styles and routes into account you would need > several individuals driving each fuel mix, as well as possibly run a > second test in which each participant was given a different mix to > drive on for a similar time period. > > The results of something like that would be FAR more impartial than > anecdotal, self reported fuel economies, which will invariably use > different methodologies, stations, fuel qualities and so on. > > As for higher cost, well... around here, all the "straight gas" > stations are charging /more/ for their product than the ones with the > "may contain up to 10% ethanol" stickers on the pumps. Sometimes as > much as 15 cents more per gallon. E10 @ $2.68 per gallon and 28.5mpg > will cost you 9.4 cents per mile. E0 @ 2.83/gallon and 30mpg will cost > you 9.4 cents per mile. Even at the more common 10 cent per gallon > premium you're spending 9.3 cents per mile, a "savings" of 1.2 cents > over the course of a (12 gallon) tank, or a grand total of $15 savings > a year if you drive 15k miles and don't ever suffer worse mileage than > 30mpg on E0. > > Yes, E10 is making us poor. Sorry, carry on. > > -Kurt > > On Thu, Oct 14, 2010 at 2:08 PM, Anthony <[email protected]> wrote: > > It may not be 33%, but it is closer to 5%. A gallon of Ethanol does > > not contain the same energy that a gallon of gas does. E10 will not > > get you as far as straight gas. You will not go as far for a higher > > cost. > > -- > You received this message because you are subscribed to the Google Groups > "Nighthawk Motorcycle Lovers!" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]<nighthawk_lovers%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/nighthawk_lovers?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en.
