The difference in weight is less than 10 pounds. If what you say is true, is that even measurable? Count me skeptical.
- Mark Sent from my Fuel Cell powered iPhone > On Aug 24, 2021, at 6:01 AM, Willie via EV <[email protected]> wrote: > > >> On 8/24/21 2:56 AM, Martin WINLOW via EV wrote: >> Mark: "In pondering what attraction a FCEV might have over a BEV, I hit upon >> an >>>> extremely minor one. BEVs do not shed mass as they are driven, while >>>> FCEVs do. So, FCEVs should see a very slight rise in efficiency as they >>>> expend their fuel while BEVs do not. I am NOT claiming that it should >>>> be a consideration when making buying decisions. But, since we are >>>> grasping for straws, it is SOMETHING.” >> This is only true for ICE vehicles in stop/go (ie urban) driving where you >> have to accelerate the mass of the vehicle up to speed and then lose all >> that energy braking to a stop again, repeatedly. On the open road and >> sticking to a relatively constant speed, the main force using using energy >> is aerodynamic drag (and tyre/road friction plus that of the mechanicals of >> the drivetrain). In an EV, much of the braking in stop/go energy can be >> recovered by regenerative braking, thus the ’shed mass’ argument is severely >> undermined. The same applies to hilly terrain. > > 1) I was comparing FCEVs and BEVs. No consideration of ICE. > > 2) No consideration of energy flows. Though I believe both FCEVs and BEVs > recover kinetic energy via regen. > > 3) To try to be clearer: A FCEV is lighter after it has depleted it's fuel. > It has "shed mass". A BEV is the same weight charged and discharged. Near > the end of the fuel supply, a FCEV is slightly more efficient than when it > has a full supply. A BEV should have the same efficiency when fully charged > and near fully discharged. > > Significant? No. We are "grasping at straws" for reasons a FCEV might be > better than a BEV. > > > _______________________________________________ > 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
