Quoted: And I understand that they can run totally on electric power from a stop, but what I was trying to say is if you're looking more than 10ft past the hood of your car, most of the time you can avoid stopping altogether, which is more efficient than having regenerative braking.
I think hybrids are a great option for a few specific types of driving, but not for most. I'm not saying they're bad, I just think they're over-rated, and a crutch for inefficient driving habits.
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You don't know how the Toyota's HSD system works.
By varying the gas pedal pressure, you can momentairly disable regenerative braking in the relatively rare event that you aren't either accelerating, criusing or actively slowing down. It is called "coasting" and is easily done at speeds of 41 MPH or lower, since that is the speed that the internal combustion engine can stop turning. Anything over that speed and the engine is freespinning if it is not using gas. Shifting into Neutral will disable regen braking at any speed. It also disables charging.
Anyway, in the example that you cited, the Prius, the car loses so little speed on a flat road that it is impossible to not use regen to come to a good stop in any reasonable length. On a flat road, the car will literally coast 2+ miles from 55 MPH. While coasting, the car is using no gas. Since 99.9% of the time, only coasting will result in smashing into the back of the last car at the stoplight at about 6 MPH less than the speed where you first are able to SEE the red light, REGEN IS NECESSARY to slow the vehicle at a rate similar to any other automatic transmission vehicle.
While anticipating a stop, you are recharging the battery. This seems far better than losing all that energy, since it is impossible under normal circumstances to "coast" all the built up energy away.
Accelerating from 0-42 MPH is possible under electric power alone, but it is pretty slow, and NOT EFFICIENT. Not to mention it is rude to drivers behind you. The most efficient way to drive a HSD vehicle is called "pulse and glide" or "brisk acceleration". The technique is to keep the ICEngine at it's most efficient speed, which is fairly high, and get up to speed faster. Once you are a couple miles per hour faster than you need, feather the pedal back to zero, and back on again to a point where the car is either coasting or is hardly using any energy to maintain speed. It is easy to get up to 50 MPH in less than 800 feet (12-15MPG), and then coast the next mile (75-90MPG) and end up far better than trying to spare fuel on the takeoff. Using battery power is NOT as efficient, since energy is lost in the conversion to storage and retrevial process. The car serves as a energy metering device. It stores unneeded energy while cruising and can dump it into a start, or in certain circumstances, a fairly long drive on electric only (up to 5-6 miles assuming flat roads and steady traffic).
Anyway, I hope this helps you understand. In a perfect world, regen would be unnecessary, but in the case of Prius, there is so little friction and drag, that the speed drop is more useful in driving than stopping.
I just wanted to add one thing. It is better to stop in the Prius than just inch forward at anything less than 5-6 MPH. The car shuts off anyway and idling is done in electric only mode. Why waste battery storage inching along at a light when you can accelerate that stretch in a far more efficient way with the ICE? At least at a stop, the electric flow stops, except to power the A/C.