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Discussion Starter #1
I know this sounds like a newbie question, and it is. Just picked up my 2017, and I'm having a hard time finding clear answers. For example, how much more efficient is regen paddle verse breaking, if there is any difference? Low vs Coasting?
Just curious what's working the best for people? Did I miss a great thread on it?
Thanks!

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Well, it has been talked to death, but...

Low, regen paddles, and light braking (before the mechanical brakes kick in) all regenerate electricity for the traction battery. Even coasting does, to a much smaller extent. Braking is obviously variable, and can cover the entire span from just a tiny bit to maximum regeneration (just before the mechanicals take hold). Coasting regens the least, then Low, then paddles. Those three all regenerate proportional to speed, and none are designed to stop the car.

The one thing to remember is: conserve your momentum. The car only recaptures a certain percentage of the energy it expends, so it's best to not waste energy by slowing with Low, paddles, or braking *IF* you can avoid it. The most obvious scenario is, don't drive in low on the highway unless you're (a) using cruise control, or (b) really, really, REALLY good at feathering your accelerator. Any momentum you lose by letting low (or paddles or coasting or braking) regenerate will cost you *more* energy to get back up to that speed than you've recovered through regen.

Personally, I fooled with the paddles for a while and then one day apparently got bored with them. Now I rarely use them, since moderate braking gives me the same regeneration that paddles would...I just have to be careful not to over-brake and let the mechanical brakes slow the car, since then I don't get the regenerated energy back.

I use Low in stop-and-go traffic. I'll also shift to low when I'm taking an exit and need a consistent deceleration.

Toy around with the paddles and Low, then figure out what makes your drive the most fun, even if it means just driving it like a regular ol' car. Keep your braking light enough that you don't engage the mechanical brakes, and nearly 100% of your deceleration will be recaptured.

--Chris
 

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Coasting is always more efficient. Not a lot of difference between the paddles and the brake. The reason coasting is more efficient is that you lose energy when converting from mechanical to chemical energy. The reason the paddles and brakes aren't a lot different is that the brake pedal will regen just like the paddles.
 

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I can do one better... Flipping into N and never hitting the brakes is most efficient, although with traffic lights and otheir traffic, you do need to use the brakes once in awhile (switch back to D before hitting the brakes as N disables regen). After trying every permutation to see for myself what is best, I've concluded that the car does just fine in Normal D, and I just drive, don't even try to eek out every EV mile any more. itn's not worth the extra brain power and making up new extreme driving tendencies to try to approach any sort of Volt mileage record (which Ari_C hold every meaningful record with no signs of anyone coming close to dethroning him).
 

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Well, it has been talked to death, but...

Low, regen paddles, and light braking (before the mechanical brakes kick in) all regenerate electricity for the traction battery. Even coasting does, to a much smaller extent. Braking is obviously variable, and can cover the entire span from just a tiny bit to maximum regeneration (just before the mechanicals take hold). Coasting regens the least, then Low, then paddles. Those three all regenerate proportional to speed, and none are designed to stop the car.

The one thing to remember is: conserve your momentum. The car only recaptures a certain percentage of the energy it expends, so it's best to not waste energy by slowing with Low, paddles, or braking *IF* you can avoid it. The most obvious scenario is, don't drive in low on the highway unless you're (a) using cruise control, or (b) really, really, REALLY good at feathering your accelerator. Any momentum you lose by letting low (or paddles or coasting or braking) regenerate will cost you *more* energy to get back up to that speed than you've recovered through regen.

Personally, I fooled with the paddles for a while and then one day apparently got bored with them. Now I rarely use them, since moderate braking gives me the same regeneration that paddles would...I just have to be careful not to over-brake and let the mechanical brakes slow the car, since then I don't get the regenerated energy back.

I use Low in stop-and-go traffic. I'll also shift to low when I'm taking an exit and need a consistent deceleration.

Toy around with the paddles and Low, then figure out what makes your drive the most fun, even if it means just driving it like a regular ol' car. Keep your braking light enough that you don't engage the mechanical brakes, and nearly 100% of your deceleration will be recaptured.

--Chris
Great response, like a fighter pilot managing momentum is critical. I always try and maximize any regen braking by trying to time my stops by lifting off the throttle early and allowing the car to slow as long as possible and avoid coming to a complete stop. Of course traffic flow and other cars will dictate my technique (I never make myself noticeable to others).

You have 4 methods to regen use all of them.
 

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The one thing to remember is: conserve your momentum. The car only recaptures a certain percentage of the energy it expends, so it's best to not waste energy by slowing with Low, paddles, or braking *IF* you can avoid it. The most obvious scenario is, don't drive in low on the highway unless you're (a) using cruise control, or (b) really, really, REALLY good at feathering your accelerator. Any momentum you lose by letting low (or paddles or coasting or braking) regenerate will cost you *more* energy to get back up to that speed than you've recovered through regen.
At freeway speeds, you don't need to be good at feathering the accelerator at all.
If you let up a bit involuntarily, your power output will drop from say, 20kW to 10kW
You're still positive, it's not wasting anything. It isn't extracting energy from the system - it's just not supplying as much.
It's only if you cross over 0 (i.e. negative kW output) unintentionally where will you be wasting energy.
At city speeds you need to be better at it as there is less room for error before you hit that magic threshold.

Either way, once you've had the car a few months, the obsession of looking at the numbers should wane and you'll end up driving it however you like and however feels natural by then. :)
 

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Discussion Starter #8
This is why I love this community already , thanks guys. It does seem like an efficiency game initially but like the some have commented I too can see that waning over time. It is interesting to gauge the physics involved in momentum. While driving today I tried to compare the difference between using Eco AC vs leaving the windows open on the highway to see if the drag created by the windows was less efficient then the energy required to use the AC. The road was not flat enough for me to create a balanced comparison but it did appear that the energy required for the AC had a greater effect than leaving the windows open. This surprised me but I could be completely wrong and I'm sure this is only been tried by almost everybody already but it is entertaining.

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I got my car 3 weeks ago and have put 4100 km on it in this time, mostly highway. I have found my technique is to use D and hold mode on highway, use cruise as much as possible, use L when in really hilly terrain which causes runaway downhill speed increase this keeping my speed closer to cruise preset and giving me a good regen amount

When in any stop and go or travelling less then 70 kph, I usually go to normal mode and if any traffic mount or stop lights use L as it is very easy to manage speed without brakes, and I use the paddle for that last bit of regen before I have to stop, then use the brake.

I'm having a lot of fun and hope the feeling doesn't wear off like some have said.
 

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I got my car 3 weeks ago and have put 4100 km on it in this time, mostly highway. I have found my technique is to use D and hold mode on highway, use cruise as much as possible, use L when in really hilly terrain which causes runaway downhill speed increase this keeping my speed closer to cruise preset and giving me a good regen amount
Yus. Just about any appreciable downslope is enough to keep D creeping up even with no input power being supplied. Which is fine if you're trickling up 2-3 MPH, but a mile long slope is plenty enough to put you a LOT faster than that. L keeps cruise control near where it's set.

(Has anyone tried to see if ACC is better about holding speeds on slopes than regular cruise control in D is?)
 

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At freeway speeds, you don't need to be good at feathering the accelerator at all.
If you let up a bit involuntarily, your power output will drop from say, 20kW to 10kW
That's actually not quite true. If reducing power from 20KW to 10KW allows your speed to drop (because you're not overcoming air resistance, rolling resistance, etc.) then you have to increase power again beyond 20KW in order to regain your original speed. Any slowdown that requires you to speed up again is going to be a waste of energy. It's not nearly as bad as actual braking, but it's still less than optimum.
 

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how much more efficient is regen paddle verse breaking, if there is any difference? Low vs Coasting?
Just curious what's working the best for people? Did I miss a great thread on it?
Thanks!

Sent from my Nexus 6P using Tapatalk
I have tried them all. My Mileage estimate after charging has been in the 80's, the last one was 84 miles. This is verified by driving the car and checking the odometer.

I will say I don't drive diffferent, per say, but I know in a gasser we get the habit of pressing the gas guzzel pedal till we come up the stop sign then we hit the brakes. Does that sound familiar?
So having said that, I find when i am in the gasser, I tend to let up on the guzzel pedal and let the car coast. I am amazed at how less often I am seeing the gas station just by that. This of course is mimicking driving in the volt to catch regen.
I find to catch the most regen there are a couple of points to keep in mind. One thing that I believe makes a difference is I use the Cruise control almost continually because it will switch to coast on a down hill road faster than we can ourselves.
I have tried to figure out how this car computes the Miles estimate. And everytime, it always seems to INCLUDE the accumulated miles that are added in while coasting in regen. Using Low or the paddles is too severe a drop in speed when compared to coasting and using the variable brake pedal. I now use the paddles to kick off cruise control. Rarely to slow the car down.
I find that the coast is gentle enough to not interfere with traffic and you get those miles that seem to be part of the miles estimate.
I figure if I were to drive up to the stop sign, not coast at all and apply the brakes, my miles estimate would be fairly low.

As you were suggested to try, use the Low and the paddles to get a feel for them and note the speed the car will slow down. Play with the brake pedal as well as that regen is variable and you can apply regen force as light ( more coasting time ) or as hard ( less coasting time ) as you need to be safe.

If I were not getting such high miles estimates I would not have commented but since my results seem to be repeated after each charge, I thought I would throw a comment in here.

Good luck, you have a lot to learn about in your new Volt. Have fun.
 

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Not sure if this has been discussed in other threads before my time, but I have to ask it.

When braking, at what point does the amount of deceleration provided by regen end and the friction provided by the disc brakes begin? I mean anyone who's used the paddle knows that a fair amount of braking is provided by the paddle to the point where using it is not comfortable to passengers, and I assume ALL of that is regen (no friction). If the traditional brake pedal is pressed hard enough to provide an equivalent deceleration rate as the paddle does and is still all regen, that would mean most of us rarely see actual frictional stopping. Heck, these brakes are gonna last forever, then.
 

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Not sure if this has been discussed in other threads before my time, but I have to ask it.

When braking, at what point does the amount of deceleration provided by regen end and the friction provided by the disc brakes begin? I mean anyone who's used the paddle knows that a fair amount of braking is provided by the paddle to the point where using it is not comfortable to passengers, and I assume ALL of that is regen (no friction). If the traditional brake pedal is pressed hard enough to provide an equivalent deceleration rate as the paddle does and is still all regen, that would mean most of us rarely see actual frictional stopping. Heck, these brakes are gonna last forever, then.
Under normal braking, it is at the very end of the stop from about 5mph to 0 mph. Friction brakes will also engage fully when tapping the brakes in N or when you are panic stopping at any speed. So for the most part, I've always encouraged the variable regen afforded by the brake pedal over Driving in L or using regen paddles exclusively. Those using the paddles thinking they are regenning as much as possible to increase range or sorely mistaken. Range is increased by not using the regen paddle if you can coast and time the traffic light changes which avoiding regen.
 

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My interest in hypermiling has never waned regardless of what car I drive.

I try to optimize my route more so than my driving but then again I naturally drive efficiently.

Coasting in neutral is the most efficient (if you don't have to stop) and timing lights so you don't fully come to a stop more so.
The real answer is to use the right tool for the situation.
Best not to come to a stop too quickly, accelerate at 20kw or less if you can, use roads that have low limits and few stops, approach hills with enough speed that you can dwl and bleed speed.

I recommend airing up your tires and reading ecomodder and clean mpg for ideas.

My record on real roads is 72 miles ev on a gen I 2013 premium . Besides Wayne Gerdes I am likely in the 99th percentile.

Do I always do this well? No but I almost never dip under 60 miles ev, going out west with 75mph speeds I had to just go and suffer .
I am very much a person who pushes the envelope but do what is needed given time and other traffic constrains.

Key to remember is you can drive more efficiently at any speed (compared to other drivers going the same speed)
All in technique.
 

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Under normal braking, it is at the very end of the stop from about 5mph to 0 mph ...
Yes. This I figured since using the paddle exclusively also doesn't bring the car to a complete stop, the friction brakes must be being utilized to halt the car below about 5 MPH.

But the key issue is matching the deceleration rate afforded by the paddle (which I assume is all regen) with the deceleration rate by applying the brake pedal. Is the latter still all regen and applying the brake pedal harder in order to obtain a greater deceleration rate starts utilizing friction? Yes, I'm sure panic stopping ultimately relies on friction, but where does regen max out and friction begin? Does the paddle provide the maximum deceleration rate that regen can provide?

(Sorry to belabor this point.)
 

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That's actually not quite true. If reducing power from 20KW to 10KW allows your speed to drop (because you're not overcoming air resistance, rolling resistance, etc.) then you have to increase power again beyond 20KW in order to regain your original speed. Any slowdown that requires you to speed up again is going to be a waste of energy. It's not nearly as bad as actual braking, but it's still less than optimum.
I disagree. I wasn't going there because it complicates the example about regen, but here goes.
The slower you're going, the less air resistance is on the vehicle, therefore the less energy used overall.
By accelerating back up to speed, you're not using more, you're just making up the difference you saved earlier (and actually slightly better off - see example below).

It's the same principle for the use of timed thermostats for home heating (which you would know is very real, if you have one or have read countless studies on)
By turning the thermostat down, you save energy because you're losing less when not home, despite having to crank up the heat when you return.
Passive heat loss is accelerated when there is a large differential between the two sides. Just like air resistance is increased the faster a vehicle goes. (It's not linear, it's exponential)

By turning your thermostat down, or slowing the vehicle down, you're spending more time at a less lossy state. So even if you add energy to the system to return to a higher energy level at a later point, your net energy use should actually be less than if you stayed at that higher energy level the entire time.
 

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Yes. This I figured since using the paddle exclusively also doesn't bring the car to a complete stop, the friction brakes must be being utilized to halt the car below about 5 MPH.

But the key issue is matching the deceleration rate afforded by the paddle (which I assume is all regen) with the deceleration rate by applying the brake pedal. Is the latter still all regen and applying the brake pedal harder in order to obtain a greater deceleration rate starts utilizing friction? Yes, I'm sure panic stopping ultimately relies on friction, but where does regen max out and friction begin? Does the paddle provide the maximum deceleration rate that regen can provide?

(Sorry to belabor this point.)
The brake pedal can give you max regen.
The difference is the paddle gives you regen and only regen.
If you press the brakes harder than max regen, it will blend in some friction braking to help.
If you want to maximize regen, you would need to learn that point, or just use the paddle for the bulk of braking and then finish with the pedal.
 

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But the key issue is matching the deceleration rate afforded by the paddle (which I assume is all regen) with the deceleration rate by applying the brake pedal. Is the latter still all regen and applying the brake pedal harder in order to obtain a greater deceleration rate starts utilizing friction? Yes, I'm sure panic stopping ultimately relies on friction, but where does regen max out and friction begin? Does the paddle provide the maximum deceleration rate that regen can provide?

(Sorry to belabor this point.)
You've GOT an instant-read power reading on the Enhanced displays. Go drive around, try things, and see when the green numbers stop going up.
 
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