Yes the wh/mi hours are painfully high. The good news is that there is plenty of room for improvement!
Your thoughts on acceleration are interesting, have you gathered any good test data on it?
At some point in my testing, once I have a good baseline, I will do a run or two accelerating at WOT up to the cruising speed on the test route.
Marginal changes in acceleration might not show as much measurable difference given all of the other variables... wind, temperature, etc.
Here are a few examples where light or heavy acceleration would change the efficiency. 1) recommendations on this site; to use a light throttle to help increase efficiency. 2) a top fuel dragster briefly makes as much power as a 747 and uses a lot of fuel to go 1/4 mile. If it were to drive the 1/4 at suburban street speeds, it would probably use less fuel.
Of course both of these examples are gasoline based, not electric. Is there a difference? Testing should provide some good clues....
Wayne
Quote:
Originally Posted by fb_bf
Before you start driving more conservatively, I wanted to point out that the energy lost in accelerating a mass to a given velocity is the same whether you do it slowly or quickly. The POWER required to accelerate faster is the difference. Your batteries store energy, so as long as your accelerating to the speed you want, (not going faster, then slowing down) it shouldn't matter how fast you accelerate. I've been waiting to bring this up in a forum to see the reaction of the people responding. For an electric car the extra losses from accelerating quickly would be related to additional I^2R losses since you driving more current to get that faster acceleration. I don't know how much that is in these motors. It might be that there isn't that much range penalty for having fun with an electric car. You really need to get an accurate assessment of the wh/m number at 50 mph. You mentioned you where doing the measurement on a road with a slight incline. Even slight inclines make a big difference. I do my measurements going both ways on a road, then average the results. My controller (soliton JR.) can log this information while I drive. That is one way to measure it. You can check out my site to see how to measure your coefficient of drag doing coast down tests. I have a spread sheet there to help. If it is confusing just contact me. I'd be glad to help. Those wh/m numbers seem too large to me.
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