On May 7, 6:25 pm, Sam the Bam <samtheb...@[EMAIL PROTECTED]
> wrote:
> On May 6, "travis...@[EMAIL PROTECTED]
" <travis...@[EMAIL PROTECTED]
> wrote:
>
>
>
> > > > I hope you how hybrid cars work...the increased mileage
> > > > comes from the decrease in wastage of kinetic energy
> > > > through regenerative braking.
>
> > > Only a small part of the overall increased
> > > efficiency. It's mostly from operating at
> > > constant, optimal engine speed. Also
> > > from the energy saved on the transmission,
> > > engine cooling, and emissions control.
>
> > Totally wrong, but don't let that fucking stop you, man.
>
> > Hybrid cars operating on the highway do NO BETTER
> > than non hybrids with equivalent drag coefficients and
> > powertrains.
>
> > The hybrid drive system is a kinetic energy recapture
> > device...that is ALL IT IS.
>
> It's basic mechanics - an engine has
> an optimal rpm, a hybrid is designed
> to run that speed continually, charging
> the battery.
>
> Braking is only a fraction of overall
> losses (though significant in city
> driving), and regenerative recovery is
> only about 30% of that. The engine
> efficiency is the main thing.
>
> Savings on water pump is probably
> as much as regenerative recovery.
>
> > They coast downhill with the engine off and do not use
> > compression braking, which adds a few mpg. I've
> > tested this shit in a non hybrid car, btw, coasting downhill
> > or on flats versus running against the engine's compression.
> > You can recover 10% mpg just by aggressive coasting.
>
> > But, again, the hybrid system, the batteries and motors,
> > are there to reclaim kinetic energy and then reapply that.
> > That is BY FAR the largest advantage, and it is moronic
> > to claim otherwise, especially
> > when you can SEE the city/hwy mpg splits.
>
> Sam
But keep in mind there are several types of hybrids these days. Many
do NOT operate at single rpm and throttle opening (they should- that
is the best way to utilize hybrid technology). Many so-called hybrids
operate engine at variable rpm and throttle, just using electric motor
to add performance boost.
There is the series hybrid (the original kind), the parallel hybrid,
and the fancy power splitting hybrid-hybrid like the Prius that is
sort of a combination of the two other forms.
While the series hybrid maximizes engine efficiency, it is a bit
heavier and thus requires more power for equal performance.
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