Niro does well in this comparison!

[TandM]

Dash pictures are all I have to work with atm. One thing that puzzles me about yours, is that 316 mi/(4.7 mi/kwh) implies a 67.2 kWh battery, not 64 kwh. That said the full size of the battery when the user invisible part of it used to maintain battery capacity by avoiding true 100% charges is something like 67.4 kWh. I wonder if your computer is using the whole battery instead the 64 kWh cap.

I did three experiments setting ACC to 70 mph and resetting the consumption info after coming to speed for some highway drives. ACC response time was set to slow since I have noticed that uses less aggressive braking and acceleration so is presumably more efficient.

The photos were taken very soon after exiting the highway each time. The first was on the somewhat hilly (but I believe overall downhill) drive on I-280 from San Francisco to the South Bay. There was enough traffic, I bet my average speed was around 66 or 67 mph.

The second is mostly flat drive on US-101 to San Jose, though I forgot to reset consumption info until I was a mile or so into the drive. The third is the same drive coming back although. I should also note on the first drive for some reason the regen braking did not kick in for most of my deceleration on the exit ramp, which partly explains the worse result.

The bottom line is there is no way I will hit 300 miles on a single charge at using ACC set to 70 mph, though these averages do take me close to the official range of 240 miles on a full charge.

Next opportunity I will try some drives at 55 mph on the same routes routes using ACC, and then do a manual comparison at about those same speeds.

The calculation for range on the GOM (Guess-O-Meter) is not a straight number of mi/kWh times battery size (it takes into account recent driving history for how economically you drive, where you are heading if you have the destination set, temperature, etc) .

A few key differences, I have both winter packages meaning my efficiency would be different than yours (I am thinking that at 55° outside you were probably running heat). I am pretty sure I have my ACC set to normal (I can check that tomorrow if needed) but I know my regen is set to 3 (because I like it aggressive and I drive a lot of hilly routes into the foothills of the Appalachians so I want to capture back all the power I can on those downhills). I rarely make short trips (all of your calculations are very short trips).

I have one drive in particular (which I had just made before the photo above) that I really have no traffic (there are times I make the drive that I probably see just a 50 cars or less in 100 miles on the highway - the drive is about 350 miles round trip with only about 5 miles not being interstate or state highway) so I have no change in speed due to braking for people (though one trip did involve stopping for a cow).

 

[David T in Silicon Valley]

Glad your values are similar. For a moment I wondered if I had something wrong with my vehicle. Well, I will try the same experiment at lower speed. Air drag does scale as v^2 so net force against the motor should be Cv^2 + F_r where F_r is rolling resistance. F_r is pretty small based on how far I can coast with regen braking off so I suspect improvement will be ~25% or about 4.6 kWh/mi. I will let you know. As for whether it is worth it, we can pick that up after we have more data.

Meanwhile....

unless you're forced to.

conjured up something bizarre in the recesses of my twisted mind.

C: Oh, heaven forbid: I am one who delights in all manifestations of the Terpsichorean muse!
O: Sorry?
C: 'Ooo, Ah lahk a nice dance 'yer forced to!​

http://www.montypython.net/scripts/cheese.php

 

[niro525]

Dash pictures are all I have to work with atm. One thing that puzzles me about yours, is that 316 mi/(4.7 mi/kwh) implies a 67.2 kWh battery, not 64 kwh. That said the full size of the battery when the user invisible part of it used to maintain battery capacity by avoiding true 100% charges is something like 67.4 kWh. I wonder if your computer is using the whole battery instead the 64 kWh cap.


I did three experiments setting ACC to 70 mph and resetting the consumption info after coming to speed for some highway drives. ACC response time was set to slow since I have noticed that uses less aggressive braking and acceleration so is presumably more efficient.

The photos were taken very soon after exiting the highway each time. The first was on the somewhat hilly (but I believe overall downhill) drive on I-280 from San Francisco to the South Bay. There was enough traffic, I bet my average speed was around 66 or 67 mph.


View attachment 7764


The second is mostly flat drive on US-101 to San Jose, though I forgot to reset consumption info until I was a mile or so into the drive. The third is the same drive coming back although. I should also note on the first drive for some reason the regen braking did not kick in for most of my deceleration on the exit ramp, which partly explains the worse result.
View attachment 7765View attachment 7766

The bottom line is there is no way I will hit 300 miles on a single charge at using ACC set to 70 mph, though these averages do take me close to the official range of 240 miles on a full charge.

Next opportunity I will try some drives at 55 mph on the same routes routes using ACC, and then do a manual comparison at about those same speeds.

I get similar results of 2.9-3.8 mi/kWh. The lower efficiency in my experience is from higher % normal driving and freezing temps.

David, temp could be a confounder. TandM lives in 84F climate. Isn't the optimal temp for the NCM battery around 75F?


David, also have you seen the paper (dx.doi.org/10.1021/am506712c)?

 

[wizziwig]

Our numbers are all in the ballpark for typical highway travel (well under 4 miles/kWh). TandM's results are an anomaly that I'm not going to try explaining because there is not enough information provided. His photo doesn't show the trip computer so can't tell the average speed. We don't know the wind conditions. We don't know the elevation changes. Temperature does play a huge role and 84 degrees not only helps the battery chemistry but also reduces air density which helps lower drag. Climate controls add more complexity. This is why I said earlier there are way too many variables to compare EV range between different owners and conditions unless you have a very large sample size or can conduct the tests under controlled and repeatable conditions (such as the indoor EPA test cycles).