Ya. They have more fingers and toes than I have. rodhall
-----Original Message----- From: Kyle Munz <[email protected]> To: [email protected] Sent: Thu, Oct 14, 2010 2:51 pm Subject: Re: [Nighthawk Lovers] Re: Slightly OT... Fuel 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]. 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. -- You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. 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