Intriguing...so the little cars are deceptive?

If the question is should you avoid EV altogether like most things in this world "it depends." If you are using the P&G on level land the idea is not to run in EV, don't use the battery, so don't recharge the battery.

However there are cases where using EV makes some sense and if you can get regen to charge the battery it can save gas. The ideal case might be stop and go traffic where you are on EV all the time, followed by a perfectly placed downhill to recharge. Even when using P&G in low speed conditions there will be traffic signals that will sometimes turn red. I will coast as long as I can to slow leading up to the red light but will drop into regen so I don't have to use brakes.

I've also found on long trips I can improve my mileage when the road is a series of small hills while not causing any real elevation change. On highway 5 in California there are places where the hills are 100-200 feet high. Go up the hill using both ICE and EV then regen on the way down.

None of these cases involves stacking up lots of "little cars in the bars" though.

 

The little green cars are a bad thing, but if you have to brake, they are better than nothing. For maximum gas mileage, you want to drive at a steady speed without every accelerating or slowing down, and have an engine perfectly matched to that one load. Obviously it can't be done, but you can try. The little green cars mean you have recaptured some energy that would otherwise be wasted, so that is good, but they also mean you have been using the brakes, which is bad. It doesn't make sense to worry about them, but don't pride yourself on how many you get.

Tom

 

You're right on target. The green emblems indicate regenerated energy, converted from kinetic energy to electric energy to stored chemical energy, with conversion losses on the way and back again when it is later used. Better is to let that kinetic energy go to work for you immediately and most efficiently by gliding instead of regenerating.

I look at this way: Every time I coast (foot totally off the go-pedal) I've wasted a little fuel. Every time I brake regeneratively I've wasted more. Every time I use the friction brakes (a hard stop or any braking below 7 MPH) I waste even more. Certainly some of this waste is unavoidable, but part of getting maximal fuel economy is route planning and anticipatory driving to reduce the need to decelerate with anything but gliding.

 

Oops, Chris, I missed this after you first posted it. :sorry:

Thanks for the kind words. The summary screen you saw is probably the one from CAN-View, an add-on device that is no longer available except to those who are converting their Prius to a plug-in version.