I think it's well established that hard acceleration is inefficient. Certainly, you should seek to avoid using the friction brakes as much as possible. You should also avoid using regen, since it only recaptures a portion of the energy required to accelerate the car; on the flat, that means lifting off the accelerator just enough to reduce current draw to zero, which has to happen much earlier than you are used to when approaching an intersection. You'll want to use regen to the minimum extent possible to slow the car as you approach a stop.
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I'm still wondering about this one. I have questions about both halves of the above statements. And yes, I know it's an old thread.
Isn't the energy usage the area under the curve? Therefore, would it be more efficient to rapidly get up to the desired speed, then lift up the accelerator pedal and run for a longer period of time using a smaller amount of energy vs slowly accelerating up to speed and staying there? In the first scenario, you use far more energy per second, but for a far shorter period of time.
In regards to stopping, if you can't anticipate a light turning red, doesn't it pay to feather the accelerator to maintain regeneration for the longest time possible, even at lesser amounts of regeneration vs keeping the car rolling as long as possible, then taking your foot off the accelerator and getting maximal regeneration, but for a far shorter period of time (perhaps 1 second at most compared to 6-10 seconds by feathering the accelerator?
Acceleration: if a single-motor drivetrain you have a simple efficiency curve which says that it's better to use less power. Also, basically, the power required to maintain speed increases more rapidly than speed. As a result slower is intuitively better. But, there's a fly in the ointment: non-drivetrain power, which includes the battery heating/cooling, cabin climate control, lighting and computer systems.
Let x be extra power of non-drivetrain use. Let s be speed in mph. Let p be power to maintain speed s. Let a be additional power to maintain speed i mph higher.
Time saved per hour = ni/n(n+i) = i/(n+i). If (1-i/(n+i))(p+a+x) < p+x, it's better to use the extra power, but given that time savings/kW will rapidly diminish with speed (as n increases, for a given a, i decreases), I suspect that the speed and acceleration windows won't be very large.
Braking:
As I understand it, yes, the general rule is to maintain steady, low regen, over none and then a lot. Decide on a point of no return in advance, and then be ready to react to the change to yellow., so you can regen low and steadily if the light changes. But, consider other drivers: when you decelerate early you reduce the available space on the road for other drivers so you may contribute to congestion behind you. Also, if approaching an I tersection with a turning lane, remember that drivers behind you may miss a cycle if they can't turn early.
is more efficient than blasting up to the desired speed.
