With recent wide swings in the unit price of gasoline, the most critical calculation is dollars per 100 kilometers whether it is accomplished by a heat engine or by an electric motor. This is best averaged from tank-full to tank-full, or full charge to full charge.
---- Original message ---- >Date: Sun, 26 Jun 2011 07:53:23 -0700 (PDT) >From: "John M. Steele" <[email protected]> >Subject: [USMA:50751] Re: MPGe = miles per gallon equivalent? >To: "U.S. Metric Association" <[email protected]> > > The trip computers aren't perfect either. > > The classic way of computing REAL fuel economy is > always fill your tank carefully to the same "full" > point, record the gallons, and divide by the miles > driven (either from the trip odo, or the reading of > the main odo at this fillup and the previous. It is > hard to get exactly the same fill, so fuel used vs > fuel added can easily differ by a gallon. It is > best to average over a few tanks. > > That is the way to compare reality to both the > window sticker and the trip computer. For alternate > fuels, you would first have to measure in the units > in which it is dispensed then convert or adapt to > using the dispensed units. (I don't understand Brits > who laboriously determine MPG when their fuel is > metered in liters.) > > ------------------------------------------------ > > From: Kilopascal <[email protected]> > To: John M. Steele <[email protected]>; > U.S. Metric Association <[email protected]> > Sent: Sun, June 26, 2011 10:35:39 AM > Subject: Re: [USMA:50747] Re: MPGe = miles per > gallon equivalent? > I would think they may have a benefactor who is > supplying the funds during the time before they sell > their vehicles and are able to recoup their costs. > Yes, the money has to come from somewhere. > > I find it humorous that in an attempt to make up new > units in order to inform the ignorant, it instead > makes it more complex. Have they figured out a way > for the average drive who has a difficulty in doing > simple calculations to figure out from their > driving how efficient their cars really are? Or > will it all be up to on-board computers to give > these people the numbers? > > It just seems that technology has become the medium > by which the old units are given an extended life. > Why change when you can have a computer convert > easily modern metric units into old fashioned > units? Between the '70s and now, the technology was > developed to make metrication unnecessary. This > isn't actually a good thing and actually creates a > greater golf between those on the metric side and > those on the pre-historic side. > > Metrication in the '70s was probably the last chance > and now with the window closed the difficulties in > dealing with the growing and prosperous metric world > can only increase, even with technology that can let > one see the numbers they prefer. > From: John M. Steele > Sent: Sunday, 2011-06-26 08:58 > To: Kilopascal > Subject: Re: [USMA:50747] Re: MPGe = miles per > gallon equivalent? > Maybe it will take them until introduction to build > the current order book. However, it would seem to > raise the question of what do they do for revenue in > the meantime. We had a plant manager who used to > say "Sometimes you have to shoot the engineers and > just make product." The manufacturing staff should > be able to make (and sell) the existing product > while the engineering staff concentrates on the new > product. > > In a quick read, the Wikipedia article seems mostly > accurate, but is dead wrong on CAFE vs window > sticker fuel economy. CAFE does not consider "well > to wheels," it is a "tank to wheels" computation. > However, it weights (by total miles) the ACTUAL > dynometer performance on each segment. Because > accessories are off, and the drive segements are not > very reflective of real driving style, those actuals > correspond VERY poor with real world (on roads) fuel > economy of typical drivers.. For the window > sticker, the city and highway figures are multiplied > by "reality factors" (which the EPA standardized) > and re-averaged by miles.. In reality, the "reality > factors" vary between classes of cars, and high > mileage cars are generally less likely to attain > their window sticker in the real world than low > mileage cars. > > ------------------------------------------------ > > From: Kilopascal <[email protected]> > To: [email protected]; U.S. Metric > Association <[email protected]> > Sent: Sun, June 26, 2011 8:26:00 AM > Subject: [USMA:50747] Re: MPGe = miles per gallon > equivalent? > You may find this of interest: > > http://mashable.com/2011/06/23/tesla-roadster-dead/ > > > The Tesla Roadster electric car is dead (see update > below). Tesla Motors announced Thursday it would > stop taking orders for the $109,000 vehicle in two > months, concentrating instead on the development of > its next-generation Model S electric car, a > four-door sedan that will cost about half as much. > > The iconic Tesla Roadster, now in version 2.5, has > been a specialty two-seater from the get-go. It > impressed reviewers with its snappy acceleration, > sporty carbon-fiber body designed (update: and > built) by Lotus, and relatively long 245-mile-rated > range. But that $109,000 sticker price for the > hand-built car — a “base price” that usually > went much higher with sport options — proved too > steep for the mass market. > > For mainstream drivers, Tesla announced plans for a > lower-priced electric car in 2008. The Model S will > sell for around $57,400 (up from its previously > announced $49,000) when it’s ready for sale in > mid-2012, according to The New York Times. > > We caught our first glimpse of a flashy Model S > prototype at the Consumer Electronics Show last > January, where we were awestruck by its sleek design > and huge instrument panel powered by an Nvidia > graphics processor. > > Update: While the Tesla Roadster as we know it is on > its way out, a Tesla Motors spokesperson tells us > “a version” of it is coming back: “The > Roadster will always be the cornerstone of Tesla, > and we look forward to bringing back a version of > the supercar that takes full advantage of our > advanced electric powertrain in the next several > years.” > > Take a close-up look at the Model S, on which all of > Tesla’s hopes are now pinned: > > > > A Wikipedia article on mpge: > > http://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equivalent > > > > > > ------------------------------------------------ > > No virus found in this message. > Checked by AVG - www.avg.com > Version: 10.0.1388 / Virus Database: 1513/3727 - > Release Date: 06/26/11
