> One more note: the drive train efficiency shouldn't be counted when > computing the effect of regen to extend range.
Quite the opposite! You expend energy on friction and windage losses when accelerating AND when decelerating. Thus when computing the efficiency of regen, you have to count those losses TWICE. You also have to consider the friction and windage losses when maintaining a steady speed. If all your driving comprised acceleration followed immediately by deceleration - no steady speed operation at all - then of course regen would recover a greater percentage of the original energy. The computation of efficiency values for this special case will be left as an exercise for the reader. ;-) =+=+=+=+=+ It seems to me that the ideal application for regen would be an airport shuttle or something similar - a vehicle which makes extremely frequent stops. Consider the Mountain Coaster, an exprimental "people mover" from the mid- 2000s, which used an electric drive with regen (and Zebra battery!). https://web.archive.org/web/20070504102744/http://www.brusa.biz/applications/ e_coaster.htm http://tinyurl.com/qypzw8e Especially with the terrain covered, I can't imagine designing a vehicle like this WITHOUT regen. Regrettably, in the page linked above, regen is mentioned only in passing. There's no discussion of the amount of energy recovered (or even theoretically recoverable). David Roden EVDL Administrator http://www.evdl.org/ _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
