wrote:

> In alt.autos.ford FanJet > wrote:
>
wrote:
>>
>>>Someone else suggests that all of the energy ultimately comes from
>>>gasoline in a hybrid. That's not true. Regenerative braking helps a
>>>lot.
>
>
>>This would be true if you only drove down hill and somehow got up the
>>hill for free. Think about it.
>
>
> If I only drove downhill, I wouldn't need an engine, but I would have to
> change the brakes frequently.
>
> While going downhill, my hybrid can use the energy that would have been
> burned off as heat to replace the battery energy that I used going uphill.
> I see this every day in my Honda, which has a battery level gauge. The
> battery level decreases going uphill, and recovers going downhill. At some
> point the batteries are full, and braking is conventional. The difference
> is noticeable.
>

But the energy to recharge the batteries still comes from gasoline. It
takes gasoline to get to the top of the hill so that you can
regeneratively charge the batteries on the way down. Yes, recapturing
this energy that would otherwise be lost to heat via the brakes is a
good thing, but it isn't a perpertual motion machine.


Matt