Generally, correct.
On 11/06/2014 07:49 AM, Robert Bruninga via EV wrote:
Energy used in driving is simple physics:
Everything you put into acceleration you get back in Momentum.
Everything you put into a hill, you get back as potential energy.
Everything you put into braking is LOST (regen gains some back).
Wind resistance goes up as the cube of speed.
True, but.... I believe, per unit distance traveled, energy lost to wind
friction goes up with the square of the speed. That is, in a given
amount of time, you cover more distance at high speed than at lower.
You experience the higher wind resistance for a shorter period of time.
So the only real control you have over energy is keeping the speed (wind
resistance) down.
Gas cars are actually MORE efficient at high acceleration when the
throttle plate is wide open and the pumping losses are minimized. So
creeping away from a traffic light does not really gain anything. BUT, if
it is a typical gas car and the engine then keeps running during the coast
phase, that too is 100% waste (engine running but doing nothing).
When people say go "light on the accelerator" they are not talking about
the rate of acceleration at all. They are talking about DON'T OVER
ACCELERATE beyond what it takes to coast to the next stop without having
to use the brakes.
Slower acceleration leads leads to lower average speed. Which leads to
lower wind losses.
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