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Tests like this should be round trips in the same temp and wind speed and direction.
It's hard to get identical results on longer tests.
With the cruise set at highway speed D or L should not matter one bit.
Hmmm... well then that is a challenge i will take to see some exact numbers... thanks Norton!!
 

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Trying something different and noting the difference isn't a test. A test controls for as many variables as possible to give assumptions about the results a high degree of probability.

A - B - A testing is a minimum testing criteria when many variables cannot be controlled. A is the initial state, B is the modification, and A is repeating the initial state again to ensure the variables in the B test didn't change much (should get similar results in both A tests). If the A tests aren't close, it suggests something changed like wind speed or direction, temperature, etc, and that the B results are suspect.
 

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Trying something different and noting the difference isn't a test. A test controls for as many variables as possible to give assumptions about the results a high degree of probability.

A - B - A testing is a minimum testing criteria when many variables cannot be controlled. A is the initial state, B is the modification, and A is repeating the initial state again to ensure the variables in the B test didn't change much (should get similar results in both A tests). If the A tests aren't close, it suggests something changed like wind speed or direction, temperature, etc, and that the B results are suspect.
Due to this is real world, I will get as close to the same as possible... but pretty sure I can't be this exact as you infer.... but point is well taken
 

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1. Race drivers are rarely coasting...no need for D mode
2. more likely, but also more complicated. These are not 1950's race cars where it is all seat of the pants and guts, they are very computerized. Likely multiple regens for different speeds and g-forces...maybe even customized to each race course.
3. I would guess they are actually similar to the Bolt in L....strong but not full regen when off the throttle, full regen available with a paddle, but with friction brakes only.

Think how much faster they can drive/how much deeper into the corners they can go fast, if they aren't as worried about overheating their friction brakes. Easier to design effective cooling for the motor and battery than the brakes
Race cars are driven with two feet, regardless of transmission type (single speed, sequential, manual with clutch), so the transition time between between throttle and brake pedal is almost negligible compared to right foot driving a two pedal road car.
 

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SN,
I did a little experiment on driving in L at highway speeds versus D... L ate up more "juice" not sure why, but I only use L for in town or below 45... does this make sense?
How big was the difference? I can imagine a lot of unrelated factors that might make a difference, but the only thing specific to "L" vs "D" I can think of is if you tend to let the speed drift up and down more in "L" mode than "D".
 

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Race cars are driven with two feet, regardless of transmission type
Left foot braking is a rare talent to accomplish, even amongst really good drivers. However some cars necessitate left foot breaking (like go carts) because there is a physical bar separating the left and right pedals.

What is interesting about the Bolt is that the Brake input overrides the throttle input allowing you to stand on both at the same time. Left foot braking can be most effective in older turbo cars where you are attempting to keep the turbo spooled. In any car it can be useful to rotate the rear end by tapping the brake with your left foot in a hard corner to upset the rear end. I have occasionally used LFB but normally find it easier and more natural to operate the brake and throttle at the same time with my right foot.
 

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Race cars are driven with two feet, regardless of transmission type (single speed, sequential, manual with clutch), so the transition time between between throttle and brake pedal is almost negligible compared to right foot driving a two pedal road car.
Yes, race cars are very often driven with two feet, but what does that have to do with anything in my post you quoted? We were only talking about varying levels of regen, and the likelihood that Formula E cars have a very sophisticated regen braking profile which may reduce the use of the friction brakes.
 

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How big was the difference? I can imagine a lot of unrelated factors that might make a difference, but the only thing specific to "L" vs "D" I can think of is if you tend to let the speed drift up and down more in "L" mode than "D".
I think it was pretty minor difference, but that is a guesstimate.... If i could drive in town commute I would only use L and I bet I could get my efficiency up to 6+ per Kwh...
 

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You don't want to be pegging torque at those speeds anyway for the sake of your tires.

Of course what hasn't been discussed much is - aggressive acceleration is often paired with more aggressive stopping. There might be some penalty for tending to regen more if you drive it like you stole it, vs. trying to avoid heavy regen.

FWIW, in my case, I hit 4.2-4.4 mi/kWh average during the summer:
AC on with recirc
On way to work, up and over a steep hill, then 45-50 MPH (speed limit 40) for a few miles, then 50 MPH (45 limit) for a few miles, a smaller up-and-over hill at 55 (maybe 1-2 miles?), half a mile at 35, then 55 (55 limit) for 6 miles
On the way home, instead of the hill I may instead do 60 MPH (55 limit) on the interstate for a longer distance - for various reasons, it's easier to do this for the return than the outbound

During winter, I average 2.9-3.0 on the same route. :(
I'm hoping to possibly build a multistage counterflow Peltier dehumidifier over the summer that will allow me to run much more recirc next winter, and get that winter efficiency up.
Do you put the heat on in the winter, or just use the seat and steering wheel warmers??
 

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I tried to explain L driving to My GF, she said it is too complicated and did not even want to try it. There will always be some that cannot adjust after learning to drive initially.
Could be a processing question. It felt really confusing to me when I read about it. I found it completely intuitive when I tried it.
 

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On this thread I asked how people got so much higher m/kWh than I did. The discussion starter said he got 4.4 to 4.6. I almost never see more than 3.9 so I was wondering if something was wrong with my Bolt.

Several people answered that they were getting numbers like 5 and 5.2.

So this morning I ran an experiment. (I'm a research engineer I do things like that.) It was a lovely late spring morning and I figured I could do without the A/C, so I turned the car on and turned off the A/C, I then plugged the charger back in and as I hoped, it thought it was a new full charge and reset the "since last charge" numbers. I reset the trip meter and the efficiency report screen. The GOM read 212 (I have the charge limit set to 90%).

I then drove as conservatively as I could stand to work (50 miles). I did not go over 60 mph, I did not go above the speed limit, I did not accelerate hard, I did not use the breaks (just the regen), I drove in L the entire time.

The first entry on the efficiency graph was less than 3. This was not unexpected because there is a hill called "the divide" that I have to climb and for about a mile the car has to expend about 60-65 kW to maintain 60 mph. After that things improved and I was at times getting graph entries of 5.5 to 6. The trip meter efficiency number went up as I drove I saw as much as 5.4 and finished at work with 5.3.

At one point the GOM started counting up. I finished after 50.2 miles with 203 on the GOM after starting with 212.

So, there is nothing wrong with the car. The problem is obviously the driver. I had to really concentrate to maintain the rules I set for the test and I felt in danger of being run over by a giant pickup truck by only doing the speed limit (it's Texas after all).

If I drove like that all of the time, I could apparently get more than 90 additional miles out of a charge. And die of boredom. I normally drive a car for all it's worth, my daily driver has always been a sporty car and I drive the Bolt the same way. When I pull out on a road I generally accelerate as hard as is safe until I am at the speed of traffic. I believe that no one should have to slow down because you entered the traffic stream (either don't pull out or accelerate hard enough you don't interfere with other drivers). I do drive 5 to 10 mph over the speed limit if traffic permits. (I actually don't think they give speeding tickets in Texas anymore, the last several times I was stopped, I just got a warning.)

So, now I know the Bolt is fine. But, I think I will just be happy with my 3.9 m/kWh and drive like me.

(Nothing here is meant to be derogatory about other drivers, those who get high mileage are probably safer, happier, more content drivers that I am.)
I am sort a frugality freak and try to get the absolute most efficiency with anything I do. I live in NC and around town with speed normally below 40 and not using AC in current warm weather, I average 6.3 miles/kwh. On trips to my daughter's house in Charlotte on regular highways I set the cruise on 55 and do use AC and average 4.8 miles/kwh. My tires are inflated to 40 psi.
 

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My wife cuts my hair and I do all brake work around here. I'm wanting to learn how to cut her hair because it costs a lot more for a woman's haircut for some reason.
It's to cover the extra liability insurance hair salons have to carry against the fury of women scorned. 😜
 

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Well at least now you know if you are low charge How to squeeze out the extra miles to get you to a charger....
Speaking of squeezing extra miles out in a worst case scenario:
Having owned a MiEV which typically had a max range of, say, 70 miles, it was a lot easier than in my Bolt to find myself in a "do I have enough to get home or to a charger" situation. The engineer types on the MiEV forum claimed that the optimum speed for maximum range was about 20mph. (Go too slow and a disproportionate amount of energy is going into overhead.)

So curious if anyone has done a test run at super slow speed on level ground to get a kw-hrs per mile and thus estimate a hypothetical maximum range creeping there? Or more useful... determine what is the optimum speed for a worst case got-to-make-it-back-to-the-house-or-charger scenario? Be kind of fun... and potentially actually useful to have a chart of miles per kw-hour vs speed flat ground.
 

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So curious if anyone has done a test run at super slow speed on level ground to get a kw-hrs per mile and thus estimate a hypothetical maximum range creeping there? Or more useful... determine what is the optimum speed for a worst case got-to-make-it-back-to-the-house-or-charger scenario? Be kind of fun... and potentially actually useful to have a chart of miles per kw-hour vs speed flat ground.
Not a Bolt, but just saw this article the other day:
New Hypermiling Record Set
And they set it at about 19 MPH so pretty close to the 20 you mentioned!
 

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So curious if anyone has done a test run at super slow speed on level ground to get a kw-hrs per mile and thus estimate a hypothetical maximum range creeping there? Or more useful... determine what is the optimum speed for a worst case got-to-make-it-back-to-the-house-or-charger scenario? Be kind of fun... and potentially actually useful to have a chart of miles per kw-hour vs speed flat ground.
I believe the record for the Bolt is 466 miles. That is actual distance, not estimated, at between 25 and 30 mph.
 

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Noticed, yesterday when I plugged it in after a trip to look at a new truck, that the miles/kw were up to 3.9. Slowly climbing as it gets used to our driving.
 
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