I am fairly sure that 65mph will lead to greater than 250Wh/mi consumption (but it will be close). 75 mph gives about 275Wh/mi.
In any case, 250Wh/mi (indicated) would result in about 290 miles of range for a full 100% to 0% discharge, by my calculations.
(1 - (65/70)^2) * 100% = 14% less air resistance at 65mph vs 70mph. It shouldn't be close at all.
I checked this over the weekend.
At 65mph, I got 255Wh/mi. (Results in 280-285 miles of range, to 0 rated miles displayed.) It
was close! Also I think at 75mph the consumption is probably higher than 275Wh/mi (probably closer to 290Wh/mi).
Data points and methodology here:
Disappointing Range in P3D. Is this normal?
I modified my statement to be a max of 85Wh/mi due to aero at 75 mph. But I said absolute max (the higher it is the better improvement you can get by going slower). I actually think it is lower than 85Wh/mi @75mph due to aero losses.
That's bonkers low. That's what I'm saying. Go look at the actual modeling of this people have done. Nothing like that.
You were correct on this, and I was totally wrong. At 65mph, it seems to be around 140Wh/mi (so more like 186Wh/mi due to aero at 75mph).
just have a hard time wrapping my head around why, if the contribution of aero is as large as you say, NO ONE reports better than about 200Wh/mi (230Wh/mi in the P3D+), for modest speeds, for the AWD. I mean, it takes energy to move the car, turn those wheels, overcome that friction.
As I said, had a hard time wrapping my head around why. But it turns out that the hill driving (where I am forced to use regen) really hurts the efficiency as that process is only 70% efficient, or whatever. That made the perceived "floor" of my efficiency artificially high. On a flat test course, my efficiency improved a LOT more at low speeds than I anticipated. In other words, due to the mandatory regen I deal with daily (hills) and general stop and go in my area, the best achievable numbers in the Performance are actually a lot lower than what I normally get.
In typical driving in hilly SD, you never get the numbers that I get on my test course. So, that threw off my perception of the true floor.
Summary:
You were right. And, steep hills matter a LOT - they will hurt your efficiency significantly, even for round trips, if regen takes place - the more regen, the more they hurt. For the same reason, stop-and-go hurts - it is crucial to avoid doing any regen, it looks like.
As for 150Wh/mi, it does fit. Go seek out those models you were talking about.
You are correct.
I fit my own model, though I need more data points of higher quality to make it better. As you said,150Wh/mi @70mph fits (it's actually maybe as high as 162Wh/mi). This model is kind of a guess, as I made up the lower speed datapoints. More datapoints on a flat course would be ideal. I haven't compared to the EPA coefficients yet as I'm more interested in my own car here, and the EPA doesn't test the P3D+ (though the aero coefficient should be fairly similar)
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And my post with discussion of this (highly speculative) model, which really needs more datapoints from a longer test course:
Disappointing Range in P3D. Is this normal?
Summary of expected ranges in ideal conditions (all to 0 rated miles - of course you can go further beyond that by several miles), using 230-235Wh/rmi constant:
55mph -> 214Wh/mi -> 330-340 miles
65mph -> 255Wh/mi -> 280-285 miles
75mph (extrapolated) -> 295Wh/mi -> 242-247 miles
These are all guesses based on my short test course, and there could be substantial error...need better data...
