GG, there's no magic in regenerative braking. With electric motors, it's easy to do as the current just does it. So there's no cost in having it. But it's trivial. I'm surprised you are one of those people like Eric who think to understand something, you have to do it. We engineers imagine all sorts of things, invent it in our minds, then design it and build it. The machine does just what it is expected to do.
If there unknown knowns or unknown unknowns things can be unexpected, but for standard things that have been done for a hundred years, it's just engineering.
For cars tootling around flat towns and countryside, with sensible drivers who know how to drive efficiently, without climbing on the brakes, there is next to no energy recovered compared with the total used. When I calculated it 30 years ago, it was nearly nothing. Nothing has changed. I was a bit surprised how low it was, as I had just assumed brakes consumed a fair bit of energy going into a car. Not so.
Yes, driving up and down a mountain transporting skiers there and back, there would be a large portion, but not many vehicles do that.
Most people driving a modern electric vehicle, or an old car, or using a Qualcomm Cyberphone, have no idea what's going on inside the machine. Driving it gives no insight. So I don't see why you think me driving an electric car would make me think that regenerative braking would provide a lot of recovered energy.
Drag, rolling resistance, thermodynamic losses and air conditioners consume the great majority [99%] of the energy going into the fuel tank of a piston powered car tootling around level lands. For electric cars, the drag and rolling resistance are the same. They lose only 10% or so of energy put into the battery in the process of getting that energy to the wheels. So they are efficient like that. But don't forget the thermodynamic losses in the power station and the line losses to deliver the electricity to the battery.
Power stations are much more efficient than a dinky little internal combustion engine in a car tootling around town, but it's not a very big deal. That efficiency gain has never been enough in itself to push people to electric cars. But it is a significant help when petrol and diesel come from $140 a barrel oil. At $30 a barrel, the incentive to go electric is reduced.
It's all just dollars and sense GG. Some people make it a religion.
Mqurice
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