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range penalty from fast starts?

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If only conservative forces were involved, the amount of energy required to get the car to 60 mph is the kinetic energy of the car at 60 mph (0.5*m*v^2), regardless of how you got to 60 mph, i.e. fast or slow acceleration. But there are non-conservative forces involved in propelling a car. Hence it makes a difference how you get from point A to point B, i.e. how you accelerate.

As an example, suppose I accelerate slowly so at the end of 1/4 mile I am going 40 mph. Alternatively, I could accelerate quickly getting up to 40 mph and then maintain speed to finish out the 1/4 mile trip. I am able to make accurate measurements of energy usage with my car (non-Tesla). In the first case, I measure the total energy required to be 0.120 kWh. In the second case, it is 0.148 kWh. Much of the difference results from the additional friction due to higher average speed for the second case. That accounts for 0.01 kWh of the difference. The remainder of the difference, 0.018 kWh, is mainly due to motor efficiency effects. The motor operates more efficiently during acceleration. With slow acceleration, you are accelerating longer and the motor is operating more efficiently longer. The remainder is due to less efficient transmission of power from the motor to the road during fast acceleration.
 
If only conservative forces were involved, the amount of energy required to get the car to 60 mph is the kinetic energy of the car at 60 mph (0.5*m*v^2), regardless of how you got to 60 mph, i.e. fast or slow acceleration. But there are non-conservative forces involved in propelling a car. Hence it makes a difference how you get from point A to point B, i.e. how you accelerate.

As an example, suppose I accelerate slowly so at the end of 1/4 mile I am going 40 mph. Alternatively, I could accelerate quickly getting up to 40 mph and then maintaining speed to finish out the 1/4 mile trip. I am able to make accurate measurements of energy usage with my car (non-Tesla). In the first case, I measure the total energy required to be 0.120 kWh. In the second case, it is 0.148 kWh. Most of the difference results from the additional friction due to higher average speed for the second case. That accounts for 0.01 kWh of the difference. The remainder of the difference, 0.018 kWh, is mainly due to motor efficiency effects. The motor operates more efficiently during acceleration. With slow acceleration, you are accelerating longer and the motor is operating more efficiently longer. The remainder is due to less efficient transmission of power from the motor to the road during fast acceleration.

It's kind of useless to compare an ICE to an EV like this, since the drive train inefficiencies in and ICE drive train are much greater and much more varied with different RMPs and gears than in an EV. [Edit, sorry, I re-read your post and you're likely referring to another EV, right?]

Also, in you example you did go the 1/4 mile in a shorter period of time when accelerating faster, did you not? That is the main reason why you spent 0.028 kWh more, not the acceleration. With slower acceleration going a given distance you take more time to go the distance, this being the main reason why it costs you less energy. It's not a coincidence the 400 mile record with the Model S was set going at an average of 30 mph, was it? However, my claim would be that the guy (and his son) would have been able to almost the same distance had he accelerated quite aggressively from 0-30 mph the times that he did need to accelerate, so long as this driving behavior didn't cause him to have to brake or let off the accelerator a little later.

Just to go all the way with my line of reasoning. Imagine you were to go a given distance and arrive at a given time. You could either accelerate slowly and reach a certain cruising speed, then hold this speed and arrive at your destination. OR you could accelerate faster, come to a slightly lower cruising speed and hold this speed and arrive at the exact same time. I would argue that in some cases you would actually use less energy accelerating fast and holding a slightly lower cruising speed. The increased losses from accelerating faster would be lower than the energy gained from less air resistance at a slightly lower cruising speed. Remember all this assumed same distance traveled at the same time (not arriving faster or going further).
 
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It's kind of useless to compare an ICE to an EV like this, since the drive train inefficiencies in and ICE drive train are much greater and much more varied with different RMPs and gears than in an EV. [Edit, sorry, I re-read your post and you're likely referring to another EV, right?]

Also, in you example you did go the 1/4 mile in a shorter period of time when accelerating faster, did you not? That is the main reason why you spent 0.028 kWh more, not the acceleration. With slower acceleration going a given distance you take more time to go the distance, this being the main reason why it costs you less energy. It's not a coincidence the 400 mile record with the Model S was set going at an average of 30 mph, was it? However, my claim would be that the guy (and his son) would have been able to almost the same distance had he accelerated quite aggressively from 0-30 mph the times that he did need to accelerate, so long as this driving behavior didn't cause him to have to brake or let off the accelerator a little later.

I am driving a PHEV in EV mode--no ICE and no gears are involved.

Yes--I end up going the 1/4 mile in a short period of time with faster acceleration. 0.010 kWh of the difference is accounted for by friction with the faster overall speed of the 1/4 mile trip with faster acceleration. The remainder, 0.018 kWh, is due to motor efficiency and efficiency in transmitting power from the motor to the road.

An electric motor is more efficient under higher load, higher output power, up to a point. During slow acceleration, you are operating the motor more efficiently for a longer period of time. It operates less efficiently when providing less power to maintain constant speed, i.e. after reaching 40 mph, the remainder of the trip uses much less power to maintain constant speed of 40 mph.
 
Can I state 0-30!=30-60? (Though it feels almost the same!)

You are absolutely right, it is not the same. The Energy needed to accelerate from 0-30 is only 1/4 of the energy needed to accelerate from 30-60. Or the other way, double the speed requires 4 times the energy.
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m = mass, v = speed, E = energy.