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I never understood why people like driving with high regen: passengers will get sea-sick, brake lights will switch on/off like a stroboscope and it costs more energy (regen is not as efficient as turning that energy into further distance). Lift your foot early from "the gas", and keep coasting.
Besides that, I think it is also more dangerous. When approaching a corner with your foot on "the gas" increases your response time compared to your foot hovering above the brake.
There is a single and very simple counter measure to everything you mention: Knowing how to drive.

Then passengers will magically not get sea sick and coasting will not be more efficient (definitely not in city driving but not even on the motorway where you don't really need to coast anyway).

As for cornering, regen is a god sent gift for drivers. You can increase your level of control over the car during all parts of cornering to levels unimaginable for a car without regen. And you're talking about "hovering your foot over the brake" while cornering. :eek:
Which driving school teaches that?

P.S. This reminded me of this clip from Top Gear:
 

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Discussion Starter · #22 ·
I never understood why people like driving with high regen: passengers will get sea-sick, brake lights will switch on/off like a stroboscope and it costs more energy (regen is not as efficient as turning that energy into further distance). Lift your foot early from "the gas", and keep coasting.
Besides that, I think it is also more dangerous. When approaching a corner with your foot on "the gas" increases your response time compared to your foot hovering above the brake.
That is very interesting and I agree with what you say. I turned regen to low because I had an accident which I think was contributed to by one pedal driving. Any driving style which means you’re less likely to be in contact with the break pedal has to be less safe doesn’t it?
 

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Discussion Starter · #23 ·
There is a single and very simple counter measure to everything you mention: Knowing how to drive.

Then passengers will magically not get sea sick and coasting will not be more efficient (definitely not in city driving but not even on the motorway where you don't really need to coast anyway).

As for cornering, regen is a god sent gift for drivers. You can increase your level of control over the car during all parts of cornering to levels unimaginable for a car without regen. And you're talking about "hovering your foot over the brake" while cornering. :eek:
Which driving school teaches that?

P.S. This reminded me of this clip from Top Gear:
I disagree with nearly all of this and it seems unfair and rather childish to say people who disagree don’t know how to drive. Objectively, passengers are less likely to feel uncomfortable if they’re not accelerating or decelerating, i.e. coasting. Nothing magical about that.
 

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I've done some statistical analysis on the data now. Sorry if you already know this but the thing to look at is the p value which assesses the likelihood that the two data sets are actually the same and the variation 'seen' is down to random fluctuation. The means of the two data sets (before accident, after accident) are 47.62 and 38.55. The p value for the two sets is 2.44 * 10e-10. So that means it's EXTREMELY unlikely that the two data sets are the same i.e. VERY likely there's been a fundamental change.
The problem with your statistics is that you only have June '22 after your modifications, and all the previous months including winter, spring, summer and fall from previously. Yes, this June is statistically better than the previous data as a whole. What you need to compare is June '22 to June '21 & June '20 etc. And even then you would need to correct for temperature variations from year to year.

I also have been paranoid about the battery and efficiency, and have the same data set starting Sept '19. I've done the same exact commute (17.9 miles) ever since buying the car. There is an annual cyclic variation (presumably temp related) of as much as +/- 15% (this might vary upon location) on top of an approximate 2% overall loss of battery capacity. All statistically significant.
The annual variation makes it impossible to simply compare dissimilar time periods, while most of us do not have enough "months of June" to allow an N>3.

Please enlighten us with your modifications and we can discuss what effect we might have expected.
 

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That is very interesting and I agree with what you say. I turned regen to low because I had an accident which I think was contributed to by one pedal driving. Any driving style which means you’re less likely to be in contact with the break pedal has to be less safe doesn’t it?
It depends if it is a "break" pedal or a "brake" pedal.🙂
 

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I’m not convinced we have the answer though. Can it really be true that changing this setting is giving me 60 extras miles per charge?
It has been documented by others on these forums, that low regen does give slightly better efficiency. For comparison, early EV's that had a "coast" setting gave more dramatic improvements, but it was very much driving style dependent.
High regen is meant to be used with subtle foot adjustments, that are not meaningful or used in cars w/o regen brakes. As such some drivers do not get the maximum benefit from high regen and experience the issues you describe such as jerky speed changes. With practice many drivers can adjust, and love the efficiency of adjusting the speed thru a corner with only a flexing of the ankle, rather than having to relocate the foot to different pedals. That, in of itself, would seem to be a safety improvement allowing better control thru corners with less foot movement.
 

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My own tests show low regen to be a about 2% more efficient on mixed driving, such as B roads and Dual Carriageways. On the exact same route of course and similar conditions. Though paradoxically high regen does regen a bit more kW but the low regen allows for a smoother drive where kinetic energy is retained more. Obviously at a fixed speed on a motorway the efficiency will be identical.

I do prefer the low regen driving style as you have to modulate your foot almost constantly in high regen mode. So personally I find it a bit more tiring unless I can set adaptive cruise on a motorway. Don't get me wrong, I know that with practice high regen is perfectly fine and is smooth.

Subjectively I also find low regen a bit safer because I have to use the brakes to stop, this means I tend to leave my right foot resting on the brake pedal until it is time to move. In high regen I have occasionally found my right foot resting on the throttle when stopped at lights/junctions because the car stopped for me and I just forgot. Some argument there for how 'sudden unexpected acceleration' happens. It's just a matter of retraining and you do get used to it.

I feel low regen drives far more like a normal ICE car under engine braking and as such is an easier transition for many EV converts.
 

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My own tests show low regen to be a about 2% more efficient on mixed driving, such as B roads and Dual Carriageways. On the exact same route of course and similar conditions. Though paradoxically high regen does regen a bit more kW but the low regen allows for a smoother drive where kinetic energy is retained more. Obviously at a fixed speed on a motorway the efficiency will be identical.
As you say, motorway efficiency should be identical (as long as you drive properly). For B roads etc. you quote a 2% improvement, which might be true, but too close to call really and could be different depending on small variations in driving style. In city driving, high regen should offer a big efficiency improvement. So, overall, with regards to efficiency, high regen is the more efficient option, excluding very specific driving conditions or erratic driving styles (constant speed variations on the motorway, coasting while cornering, lack of control of the accelerator pedal etc.).

Don't think that Tesla's decision to only offer high regen didn't take the above into account.

In terms of preference, to each his own, obviously.
 

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As you say, motorway efficiency should be identical (as long as you drive properly). For B roads etc. you quote a 2% improvement, which might be true, but too close to call really and could be different depending on small variations in driving style. In city driving, high regen should offer a big efficiency improvement. So, overall, with regards to efficiency, high regen is the more efficient option, excluding very specific driving conditions or erratic driving styles (constant speed variations on the motorway, coasting while cornering, lack of control of the accelerator pedal etc.).

Don't think that Tesla's decision to only offer high regen didn't take the above into account.

In terms of preference, to each his own, obviously.
I would say it would not even differ that much in any environment with an I-Pace, because the I-Pace does regen on braking, so even city driving is no different. There is nothing to suggest either is significantly more efficient overall, at least with the I-Pace as it does not have true coast mode. My wife would not even drive the I-Pace until I turned regen to low and creep on. Her very logical response to high regen was "what's the point?" and I couldn't give a reasonable reason why it was better, because it isn't IMHO.

There is a significant difference between coast mode and one pedal driving around a city and it's not what you would assume.

EV6 10% higher consumption with one pedal driving vs coast.

EQA 21% less efficient in one pedal driving mode in urban driving

Only the E-Niro was close between both but was still 6% less efficent in one pedal driving.

Fairly conclusive really.
 

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I have a 2019 iPace.
I had an accident and when it came back after being fixed Feb-May 2022 I made 2 config changes.
I'm attaching a plot of the kWh/100 miles smoothed over three journeys.
What do you think I changed?
I'm still driving the same journeys every day. It's a big mystery to me.
View attachment 7441
The weather has got warmer?
 

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Discussion Starter · #32 ·
So looking at the temperature question, I've produced a chart which shows the same days this year (11 May to now) compared to last year. I'll do a p-test on it later but it looks clear to me there's a change.
Rectangle Azure Font Slope Parallel
 

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There is a significant difference between coast mode and one pedal driving around a city and it's not what you would assume.
I just watched the beginning of the EQA video. He says, and I quote:

"the first two laps I try to regenerate as little as possible, or to use a different word, brake as little as possible, keeping the car in motion and avoid a change of speed"
and
"in lap 3 and 4 I will do the opposite, trying to brake more and regen as much as possible"

This is NOT a comparison between high regeneration and no regeneration. It's a comparison between two completely different driving styles, with the former obviously being much more economical than the latter. It's like comparing motorway efficiency when doing 60mph behind a truck and doing 90mph in the left lane.
 

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I'd say its mostly personal preference, mine is low regen, but a country lane would benefit from high regen. For novices I'd recommend low regen and creep. A live button to toggle would be great, but also it could run from the cruise control radar/camera, but that may not appeal to the elf and safety dept.

I suspect the current UK weather is pretty good for range, as its sitting about 20 deg C, so not much aircon use. I did 36 miles today, and only used 24 miles of range.
 

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I just watched the beginning of the EQA video. He says, and I quote:

"the first two laps I try to regenerate as little as possible, or to use a different word, brake as little as possible, keeping the car in motion and avoid a change of speed"
and
"in lap 3 and 4 I will do the opposite, trying to brake more and regen as much as possible"

This is NOT a comparison between high regeneration and no regeneration. It's a comparison between two completely different driving styles, with the former obviously being much more economical than the latter. It's like comparing motorway efficiency when doing 60mph behind a truck and doing 90mph in the left lane.
English is not his first language, you need to watch all of it. He does go into detail of each driving style and his terminology (3.09 and 5.00 in the EQA video). He is not saying he doesn't brake, he means he coasts as much as possible until he needs to accelerate or brake, at which point the car will regen. When is is doing the one pedal mode he is still modulating speed to optimise regen and coasting. Whatch the videos to see how he is keeping roughly similar speeds around the laps.

They are totally different driving styles and one pedal mode relies on you modulating the throttle a lot to get the same level of efficiency and requires a lot more work to maintain the "coast".

I have driven enough EVs in both modes to know that high regen mode is not actually more efficient. In fact until you get very proficient at modulating the throttle it will be quite a bit less efficient IMHO. It is a placebo because you feel the car slowing down and see the little regen dial go green.

Have you tried both to see if you find a difference in the I-Pace? I personally havn't seen much but I suspect it is because the I-Pace doesn't actually coast and always used regen brakes regardless of mode.
 

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If anybody wants to have a go with my data, I've augmented it with the temperatures in London on each day and it's here:
Having the temperature data is one thing, knowing the effect it has on your efficiency is another. For example, over a certain range increasing temperature will lead to greater efficiency, but at a point the battery management system kicks in as the temp rises and your efficiency will drop. Do you know these parameters? In addition, what temp do you set the cabin? External temps above and below this will have contrasting effects. Wind and humidity conditions, will make a huge difference, and I doubt that you have these for the duration of these trips.

The bottomline, and I believe the point I have been trying to make, is that your data is not very different, and any small differences in efficiency associated with driving mode or style are going to be lost in the effects of climate noise.
 

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Discussion Starter · #40 ·
Having the temperature data is one thing, knowing the effect it has on your efficiency is another. For example, over a certain range increasing temperature will lead to greater efficiency, but at a point the battery management system kicks in as the temp rises and your efficiency will drop. Do you know these parameters? In addition, what temp do you set the cabin? External temps above and below this will have contrasting effects. Wind and humidity conditions, will make a huge difference, and I doubt that you have these for the duration of these trips.

The bottomline, and I believe the point I have been trying to make, is that your data is not very different, and any small differences in efficiency associated with driving mode or style are going to be lost in the effects of climate noise.
Are you saying that my extra 60 miles range per charge is what we could expect from changing the regen given about the same temperature?
 
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