Well, until you start going uphill then weight becomes significant again. FWIW, back in the day I noticed that my diesel F-250 was significantly better at coasting than my other vehicles. Yeah it had crap aerodynamics, but 3 tons of inertia does make a difference
My PGP public key: https://vanderwal.us/evdl_pgp.key December 30, 2021 6:02 PM, "Bill Dube via EV" <[email protected]> wrote: > On 12/31/2021 4:17 AM, paul dove via EV wrote: > >> Well, that’s not how efficiency is measured but I think I know what you >> mean. The Wh per mile is >> mostly a function of weight. Aero starts to weigh in around 55mph. On >> conversions a good estimate >> is weight divided by 10. My car weighs 3100 lbs with me in it and I got >> around 300wh/m. Tesla beat >> this by making the battery a larger percentage of total weight by using >> aluminum. No one else comes >> close. I think the Bolt is close to the rule of thumb. > > At the wall is probably the best way to measure efficiency. It is > what the consumer cares about most. That is what I would care about, for > sure. > > Weight doesn't make nearly the difference in efficiency as does the > frontal area. > > Often, the weight of a car is sometimes reflected in the frontal > area, however, but there is not much correlation. > > Rolling resistance is roughly proportional to speed (and the > weight,) while aerodynamic drag is proportional to the frontal area and > the _cube_ of speed. That cube term adds up very quickly. Aero drag > starts to dominate at about 30 mph. Nothing else matters much over ~60 mph. > > Bill D. > > _______________________________________________ > Address messages to [email protected] > No other addresses in TO and CC fields > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > ARCHIVE: http://www.evdl.org/archive > LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org _______________________________________________ Address messages to [email protected] No other addresses in TO and CC fields UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub ARCHIVE: http://www.evdl.org/archive/ LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
