Hey there,
I recently acquired my first EV and have been having fun trying to get the best efficiency numbers out of it. I was at ~3.5mi/kWh (5.6km/kWh), but by slowing down and taking the other road not the highway to work I got it up to 4.4mi/kWh (7.08km/kWh). Part of that was accelerating relatively slowly as this is one tip that I heard. But I’ve been thinking about it and from a simple physics calculation it should take basically the same amount of energy to accelerate an object to highway speed whether you do it very quickly or if you spread that energy over a longer period of time.
Does anyone have any insight? I don’t mind granny accelerating but if I can have the zippy fun of accelerating an EV while still staying efficient that would be awesome too :)
Thanks!
I can only speak anecdotally, but the anecdote comes from years of driving an ev. When I’m driving, the first ~8 miles I have to drive to get anywhere involves a long sequence of stop and go lights. I’ve experimented with both aggressive and very conservative acceleration in this, and what I’ve found, is that it really, really doesn’t matter.
Its practically the same. My thinking is basically that energy = energy. As long as I’m not overshooting the target speed, the rate of acceleration isn’t relevant. It takes the same amount of energy either way (in terms of observed, battery based kwh). Basically, if your target speed is the same, it doesn’t matter if you are getting to that target speed faster or slower. It takes the same kwh to get the big lump of mass from rest to that speed.
Now where I do find efficiencies is in what that target speed is. Even a bit of traffic massively increases my battery efficiency.
The bigger impact is shedding that speed I think. If you jackrabbit then brake for the next light, it’ll kill the battery even with regen.
absolutely. ideally you don’t use any brake whatsoever. breaking is absolutely the enemy of efficiency.
and jackrabbiting works if it allows you to stay in rhythm with the green lights not having to use the brakes. but you should imagine braking as basically “throwing away” energy, even with regen.