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Kona PremSe64k 2020+bluelink +ohme
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Discussion Starter #1
If you go through setup on a Kona (and I guess this goes for other Hyundai and Kia EVs, if not others) you can profile your car to use different recuperation levels by default, different climate control settings by default and other bits. In the UK These are summarised as Eco, Comfort and Sport. in other zones I think at least Comfort is known as Normal. But whatever that's just a name. What matters is the impact of these. Now in setup there is a percentage marker which tells you the "echo potential" of a given profile. This ranges from a 100% for eco this that and the other down to 45% in sport, sport, sport.

So, let's assume best case. Does this "eco potential" mean that you can drive twice as far in all-bells-and-whistles eco mode when compared with fast-as-you-like, air-con running at full pelt? With gradations between...

Or is it just irrelevant BS & sales-pitch.
IMG20200618 OorKona 0003 EcoPot=100% Drive=Eco.JPG IMG20200618 OorKona 0014 EcoPotential 45% Drive=Sport CC=Normal Recup=L3.JPG
I think it might be a useful video to drive the same journey in several modes, top & bottom and average perhaps to see if these percentages can be lived out!

(I guess what prompted this question were comments on FB that some people felt zero recuperation could yield better mileage than recup level 3, with the correct driving style. Hmmm.)
 

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The biggest single difference (outside of weather conditions) will be your driving style. The eco (and eco plus) settings will net you a few percent extra range at most. This will help if you somehow find yourself running very low on range. But really the range is so high, and efficiency so good that I've never found myself close to running out range. As long as you plan your stops sensibly, with back ups you shouldn't worry.

FWIW I find having regen set to 0 provides the best range. I do tend to use the paddles to slow down, but really it makes no difference to using the brake pedal and that will also use the regen in the first instance.

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2020 Hyundai Kona Premium SE 64kWh, Ceramic Blue
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When sitting in a queue with the foot brake depressed, does the car use energy pushing forwards (creep)?
Same question when the car has been stopped using the left paddle?

Any ideas?
 

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When sitting in a queue with the foot brake depressed, does the car use energy pushing forwards (creep)?
Same question when the car has been stopped using the left paddle?

Any ideas?
1) I would have thought it is using power when the foot brake is depressed, but I tend to have the hold function on in traffic.

2) pulling the paddle to stop applies reverse torque to the motor, so yes, I would expect it does use energy to hold it there. I've always wondered what would happen in a shunt in that situation. If the car is hit from the rear would it damage the motor??

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I would have thought it is using power when the foot brake is depressed
Even modern ICE automatics have the sense to disengage the creep function while the brake is pressed. I think most EVs would do the same.
Of course the brake lights will be on which is a fair current for non-LEDs.

pulling the paddle to stop applies reverse torque to the motor, so yes, I would expect it does use energy to hold it there
If it kept reverse torque on once stopped you'd start going backwards.
There is probably some power applied to hold it (I'm not au fait with the type of motor) but it's probably small compared to all the other car systems that are drawing power anyway.
 

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When sitting in a queue with the foot brake depressed, does the car use energy pushing forwards (creep)?
Same question when the car has been stopped using the left paddle?

Any ideas?
Energy consumption whilst ON can be seen as a menu item on the Centre Console. The results generally show some electrical power used in most situations including whilst stationary in Park with foot off the brake pedal. I monitor that information all the time.
 

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The biggest single difference (outside of weather conditions) will be your driving style. The eco (and eco plus) settings will net you a few percent extra range at most. This will help if you somehow find yourself running very low on range. But really the range is so high, and efficiency so good that I've never found myself close to running out range. As long as you plan your stops sensibly, with back ups you shouldn't worry.

FWIW I find having regen set to 0 provides the best range. I do tend to use the paddles to slow down, but really it makes no difference to using the brake pedal and that will also use the regen in the first instance.

Sent from my SM-G986B using Tapatalk
I picked my Kona EV up in Sept 2018 and immediately started experimenting by recording statistics over a common outward and return 10 mile daily journey. This was achieved by a video camera monitoring appropriate car instruments and location stamping by voiceover at pre determined points - mostly on free flowing dual carriageway with gradient changes of over 900 feet. The info was then transferred to a graph.

After a couple of thousand miles I concluded that there was little difference between the various driving modes and in the end settled for 0 as being slightly more efficient, with my driving style. A few experiments later I felt that there was also some advantage to use the left paddle on a steepish decent to keep the speed down and to harvest some energy for later use. Perhaps this is because the electrical conversion losses in that scenario are less than losses due to Increased drag at higher speeds, even when freewheelng. I do not use the Paddles in other circumstances.

In carrying out the experiments, it always surprised me how different the results were in what appeared to be identical circumstances. I therefore appreciate the many variables that can alter the result on any particular journey. To counter my frustration I changed the Consumption Readout to reset each time after Charging, rather than the other options. By averaging the results in this way the figures are more consistent.
 

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... (I guess what prompted this question were comments on FB that some people felt zero recuperation could yield better mileage than recup level 3, with the correct driving style. Hmmm.)
'Hmm', right back! I think it's obvious that regen level zero has the potential to be the most efficient. The primary influence to motivation efficiency is, not surprisingly, losses. Aside from driver choices such as speed, the one other place the driver can influence that is by not incurring unnecessary regeneration losses. This is most likely to happen when you momentarily relax your foot off the 'go' pedal with regen set at levels 1-3. Just like braking on an ICE incurs 100% loss of energy during application, using regen on an EV incurs roughly 25% loss. If you have a very steady foot, the regen level set would not make any theoretical difference. If you don't, regen at level zero will conveniently eliminate this source of loss when unintended. (Older folks might remember that freewheel devices at the driveshaft were sold for fuel savings long ago.)
Using the brake pedal uses regen exclusively when within the limits of regen (depends on speed) right down to about the last meter of travel. It has the advantage of requiring a conscious effort to apply and so won't kick in every time your foot relaxes off the accelerator.
The drive modes offer only a recalibration of the accelerator and limited climate functions in the case of ECO+, with the goal of encouraging more efficient driver behaviour. I don't see any possibility that efficiency of power conversion and losses from the vehicle traveling from A to B can be otherwise affected by the different modes.

When sitting in a queue with the foot brake depressed, does the car use energy pushing forwards (creep)?
Same question when the car has been stopped using the left paddle?
Well, the engineers would have to be absolute idiots to not get those right. But, when the left paddle is used the mechanical brakes are not in play and every servo motor uses a small amount of power to hold a fixed position, relative to the residual torque (the slope you are on.) Note that in Auto Hold mode the mechanical brakes are used rather than the motor and that would certainly incur less losses, however small they are.
 

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But, when the left paddle is used the mechanical brakes are not in play
Are you sure about that?
They are used by the SCC when it stops the car and (you say - I rarely use it) for Auto-hold, so why would they not be used for other 'pedalless' braking?
 

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Discussion Starter #10
Thanks for a lucid description.

Have I got this right. For the most economical driver ie putting the emphasises on a person whose goal is economic driving and knows how to do it THEN regen0 is best because any regen by definition loses energy, possibly 25%.

But most Kona owners aren't in that mold. Most people just want to get from A to B and know they have been reasonably efficient and have enough battery left, say 10 or even 20% at arrival.

So for this second category of driver, is regen0 still best?

Btw I have in mind as an example myself and my wife. I want to explore best practice in all its forms. My wife wants to get on with life!
 

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Thanks for a lucid description.

Have I got this right. For the most economical driver ie putting the emphasises on a person whose goal is economic driving and knows how to do it THEN regen0 is best because any regen by definition loses energy, possibly 25%.

But most Kona owners aren't in that mold. Most people just want to get from A to B and know they have been reasonably efficient and have enough battery left, say 10 or even 20% at arrival.

So for this second category of driver, is regen0 still best?

Btw I have in mind as an example myself and my wife. I want to explore best practice in all its forms. My wife wants to get on with life!
What you have to remember is, that every time you slow down, you have to speed up again. Say you use regen to slow down and get back 1 Watt/hour, and then use 10 Watt/hours to accelerate again, your net loss is 9 Watt/hours. However, if you let the car coast and get no regen and then accelerate using 5 Watt/hourss, your net loss is only 5 Watt/hours.

It all depends on the traffic and the terrain. I use the pedals if I see a queue of traffic up ahead and know I will be slowing to a stop. I use no regen and let the car roll if the traffic is still moving at a reasonable pace, and I use full regen for going downhill. (From the top of Cheddar Gorge to the bottom I can get 2 to 3 miles of range back).
 

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I'm with Gadget Geek on this....a great explanation. We use this method, and get great economy from the Ionic 28.
We select zero regen, and try to look forward a few hundred metres to anticipate traffic flow. If things are slowing down more than coasting will take care of we use the paddles to adjust the speed. Whilst braking using the foot pedal is also regenerating, you feel as if you are in better control of the regen (that is very subjective I know). The results speak for themselves over 22,000 miles done so far, on all road types, and we had experimented all styles widely in the first 5000 miles. In the summer months most journeys are in the 5.5 to 6 miles per kWh (x28= 154-168 miles theoretical range. In practice we consider 125-30 'normal' and 140 'achieveable' if desperate). With your 64kWh Kona you might not need to be so frugal but it's good to know you can do these things with zero regen if circumstances required.
 

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I'm with Gadget Geek on this....a great explanation. We use this method, and get great economy from the Ionic 28.
We select zero regen, and try to look forward a few hundred metres to anticipate traffic flow. If things are slowing down more than coasting will take care of we use the paddles to adjust the speed. Whilst braking using the foot pedal is also regenerating, you feel as if you are in better control of the regen (that is very subjective I know). The results speak for themselves over 22,000 miles done so far, on all road types, and we had experimented all styles widely in the first 5000 miles. In the summer months most journeys are in the 5.5 to 6 miles per kWh (x28= 154-168 miles theoretical range. In practice we consider 125-30 'normal' and 140 'achieveable' if desperate). With your 64kWh Kona you might not need to be so frugal but it's good to know you can do these things with zero regen if circumstances required.
I also learnt this method in the Ioniq 28kWh. Great car.
 

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Are you sure about that?
They are used by the SCC when it stops the car and (you say - I rarely use it) for Auto-hold, so why would they not be used for other 'pedalless' braking?
If you recall complaints about a year back or so about left-paddle-hold rolling back slightly after stopping illustrate the point, as does that it slows but fails to hold while rolling back in N. When starting off again the transition to motion is silent.
In Auto Hold mode the brakes reveal no rollback and furthermore make a clunk noise when starting off again on a downhill slope.
Hyundai could have designed these modes anyway they wanted because all the required hardware is in place. Why they did these modes differently will probably remain a mystery.
Have I got this right. For the most economical driver ie putting the emphasises on a person whose goal is economic driving and knows how to do it THEN regen0 is best because any regen by definition loses energy, possibly 25%.
Perhaps I could have been more clear. Regen is only roughly 75% efficient at recovering energy while slowing down no matter by what method it is called into play, by paddles or by pressing the brake pedal. The advantage of using regen level zero as much as possible is to ensure that the application of regen requires the conscious effort of applying the brake pedal, or even temporarily entering into other regen levels. Otherwise, with higher levels especially 3, every single time you release the accelerator the car regens whether you want to slow down or not.
But most Kona owners aren't in that mold. Most people just want to get from A to B and know they have been reasonably efficient and have enough battery left, say 10 or even 20% at arrival. So for this second category of driver, is regen0 still best?
Sure, I was only addressing the question you asked, IMO of course. For myself and probably most drivers convenience and comfort is the far greater priority. In any case the differences we are talking about are based on theory (basic physics and motor control systems) and are likely small, perhaps less than 1%.
 

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But regen is good for battery health. So happy to keep mine on.
It's not possible to turn regen off since the brake pedal system uses it to simulate friction braking right down to the last meter. Every mainstream EV has done this sort of thing right back to the GM EV1.

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