BTW regen is more like air brakes than friction brakes. It will help slow your car down (in a much more efficient manner than friction brakes) but it is not used to stop the car because the slower you go the less affect regenerative braking has (diminishing returns).

While regenerative brakes are practically useless in a panic stop they work great to slow the car down over longer distances, like long downhills or preplanned stops.

Air conditioning adds noticeable drag of its own. If one wanted to minimize friction brake usage they would maximize regen and turn the AC and "b" mode on.

I have no doubt that the friction brake pads in my hybrid will last much, much longer than brake pads on a normal car. The way I drive they are typically only used after the car has already slowed down under 20 mph.

 

AC runs off the battery, not the engine like non-hybrids.

 

True, Phil. But what he is saying is that any increase in electrical load provides a means to accept more charging current to replace that used for the load -- so more regen braking can be used.

In other words, use your AC when going down a long grade to enable increased regen braking capacity. A very subtle, and smart hint.

RFB

 

By that measure why not turn on ALL lights, seat heaters, windshield defrost (Canada only) and the radio up to full VOLUME.

 

'Cause I am only a mild hypermiler and not a real cowboy!

(Heck, I wouldn't even use the AC if it was already too cold in the cabin.)

RFB

 

I've posted before that regen braking, (B Mode), slows my wife's car down too much unless the hill or mountain is really steep, (AC on, ECO Mode on). Therefore, I don't use the B Mode very often at all.
BTW, I live in WV.

 

"B" mode enables engine compression braking during coastdown and in general will reduce the level of regen braking to be used.

 

Thanks for correcting me, now I know why it slows the car too much in the B Mode.

 

Indeed. Any major power sucker would help slow the car down. Of course "b" mode is generally not efficient so use should be kept to a minimum if MPG is your goal. I'm not sure why you would ever want to maximize drag, maybe if your friction brakes went out on a downhill? Heck might as well open the widows or open all the doors to make a real air brake in such a case .

 

Phil,

The friction brakes are used below 7 mph and in panic stops (you can also force them to be used by shifting to neutral). Regen in our hybrids currently manages to recapture about 50% of the energy that would be dissipated as heat in the friction pads. More efficient battery charging can improve this in the future as higher capacity batteries and/or ultracaps have lower losses when being charged and discharged,

JeffD