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New Bolt owner here. It indicates full charge at 219 miles (solid green). Why won't it charge to 238?

Also, I cannot open the center console. Before I take it to the dealer, any thoughts?
 

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If you drive it hard, the range is lower because it's based on your MPGe from your miles per kilowatts.
Look on the drivers display and pull up your average info. It will be lower than 4 and closer to 3 miles per kilowatt.

Push the console lid towards the rear seats. It slides and will not allow it to open when in the forward positions.
 

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Any possibility it is set in "Mountaintop charge" mode? That always stops the charge below full, thus leaves room in the battery for regenerative braking gain for those who live in Park City and have a 20-mile downhill run into Salt Lake City.

jack vines
 

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Thanks, I will look at the setting though it would be a default one since I didn't touch it.
Is mentioned earlier, it's most likely that your driving habits have been getting you lower mileage than the EPA estimated profile. The range is calculated off of a trailing average of your actual achieved habits, and it you have been doing a lot of high speed freeway driving, driving up hills or other low efficiency activities, that trailing average will be lower, and your calculated range with a full charge will be lower.

In your energy screen, look for your "Energy Usage Score", and that will give you a feel for whether you're getting the MPGe they are expecting.
 

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Another new Bolt owner here. Our is indicating full charge at 206 miles and we have just 487 on the Odometer. I'd say we're not driving it hard. We do live half way up a hill in LA but not a massive hill and we're not in Hilltop mode. I'm not sure how to interpret the energy usage score. And on the "Efficiency History" page is that showing how it performed over the last 50 miles? So likely between miles 20 and 25 it was going down hill?

Thx

OP
 

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Cool! I didn't know the car gave feedback on where energy is being spent, and how you're doing compared to baseline. This makes it much easier to see where to improve habits, or at least explain why you get the results that you do.
 

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Another new Bolt owner here. Our is indicating full charge at 206 miles and we have just 487 on the Odometer. I'd say we're not driving it hard. We do live half way up a hill in LA but not a massive hill and we're not in Hilltop mode. I'm not sure how to interpret the energy usage score. And on the "Efficiency History" page is that showing how it performed over the last 50 miles? So likely between miles 20 and 25 it was going down hill?

Thx

OP

Two things to know.

1. To get the 238 EPA estimated range (and estimate on the display) you will need to average 4 kWh (nice round number, really it is 3.9667 kWh, also why the red line average is just slightly below the 4 kWh line) over at least the last 50 miles prior to charging. There seem to be some other driving factors that can influence it but after watching it a lot over the past almost 9,000 miles it seems to be the last 50 miles that are the biggest influence.

2. The range is adjusted when you have climate control on (AC or Heat) I saw in your picture the AC is running, that will lower the estimate by at least 10 miles, sometimes more/less depending on how hard it is working. It seems to just automatically take 10 miles off the range when it is running though. Next time you are in your car have the AC on look at the estimate then turn the AC off and watch it go up (or vice versa if you get in with it already off)


One way to improve technique is to watch the ring around the speed on the driver display. It is green while you are doing "good" and fades down to yellow when you are doing "bad". If you watch that and try and keep it green as often as you can you will start to get a feel for how to improve your technique. Myself I drive in L a lot as I have quite a bit of stop and go. So I let L do most of my braking. I have gotten pretty good about the feel of the pedal of when it starts to brake and not. Another good trick is switching between D/L while driving. When I am on the highway and the traffic is moving good I switch to D and coast a lot. That saves a ton of energy. When I see traffic ahead I will put it back in L and let that brake for me. I like the L braking more than the paddle on the steering wheel. I don't like always needing to have my left hand in one place, and a place my handle doesn't like to naturally sit. If you like where the regen paddle is on the steering wheel you can stay in D the whole time. When you hold that paddle down in D but push the accelerator it reduces the amount of regen braking it does. So once you get the feel of that you can have the ability to coast on demand with the same regen braking ability of L without needing to switch between L and D. I just prefer the switching myself, personal preference. I am sure there are others who prefer it with D and using the regen paddle.
 

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Pete
Thanks for helpful reply. Yes I noticed the green ring turning to yellow obviously nudging one to keep it in the green. It's been hot in LA (100 degrees today) so no surprise about the AC and consequent reduction in range. I haven't played with the paddle but have tried L mode a few times. I presume this must set it up to turn on the rear brake lights as soon as it's decelerating. Definitely good for stop/start traffic.
 

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Pete
Thanks for helpful reply. Yes I noticed the green ring turning to yellow obviously nudging one to keep it in the green. It's been hot in LA (100 degrees today) so no surprise about the AC and consequent reduction in range. I haven't played with the paddle but have tried L mode a few times. I presume this must set it up to turn on the rear brake lights as soon as it's decelerating. Definitely good for stop/start traffic.
In L the brake lights activate at .1g of deceleration. They don't stay on while stopped though, so if you use L to come to complete stop you will need to put your foot on the brake to have them on while you are stopped.
 

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When I am on the highway and the traffic is moving good I switch to D and coast a lot. That saves a ton of energy.
Can those more techno/math savvy quantify this? I'd believe it on a hypermile ICE, but it isn't consistent with my empirical EV experience.

jack vines
 

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In D or L, on hilly terrain, using cruise control, our Bolt maintains the set speed within plus or minus a mile an hour...better than any car we have owned. Unless you are driving in heavy traffic, driving the speed limit, or slightly less, in cruise control, will be the most efficient way to go. Coasting will not save energy. Rolling downhill at faster than your average speed, will raise your average speed, but do nothing to conserve battery energy. In uncongested driving situations, cruise control will get you to your destination, at your selected average speed, better than you can do manually adjusting throttle position, and coasting, etc.
 

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Can those more techno/math savvy quantify this? I'd believe it on a hypermile ICE, but it isn't consistent with my empirical EV experience.

jack vines
There isn't any math needed. True coasting expends no energy from the battery to drive the vehicle forward, granted you will of course slow unless you are going on a decline. If you push the accelerator pedal down just a little bit you can negate the tiny bit of regen braking the bolt does while in D and get close to a true coasting experience (still not perfect because there is a small amount of drag from the engine still), you can almost do the same thing in L but it is a lot more touchy. The problem with most EVs and this is that they don't have true coasting abilities. I mean you could shift into neutral which I always did in my cars since they were manual, going to neutral and back into gear was just second nature. I'm not comfortable doing it in an automatic right now and honestly I need to read up to see if it is even ok to do on the Bolt. I assume it will let you shift to neutral while driving but I am curious if shifting in and out of neutral could cause issues. Especially because of some reports of cars having weird shifting issues. But like I said above, you can come close to a true coast if you feather the accelerator pedal just right in D, same in L but it is just touchier in L so a little more difficult. So it may be perfectly fine to switch in neutral while driving to actually get a true coast but I prefer to stay in gear and just feather the accelerator.

You will never recover the same amount of energy from regen braking that you spend accelerating, physics and the laws of nature don't allow it. To accelerate the car has to spend enough energy to move the mass of the car, overcome rolling resistance, overcome wind resistance and overcome mechanical energy loss (no idea how much the bolt has of that since the system is much simpler than an ICE car). It is literally not possible to recover that same amount of energy while using regen brakes. The car is still being pushed against by wind and rolling resistance. So you are already negative just from those two factors. Now you have to account for energy lost during regen recovery due to heat and mechanical energy loss, this goes to the efficiency of the regen brakes themselves. So now two more negatives taking away energy from regen braking.

So if we are looking at trying to conserve energy the first goal should be to use techniques that don't expend any energy. In a car coasting is the closest you can get to spending no energy. So when traffic and road conditions allow coasting is the spend no energy option. (Yes energy is still being expended in all kinds of ways, but I of course mean battery energy to push the car forward). After that the next best way is when you actually need to slow down and you can't coast because you won't stop in time, regen brakes as much as possible. Then acceleration, gentle acceleration is the most energy efficient way of course.
 

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In theory there would be no downside to coasting down the hill, as long as you reapplied just the right amount of power, at just the right time as the car decelerates back to your chosen speed. In practice, this is extremely difficult. You either give it juice too soon, causing it to overshot your chosen speed unnecessarily, or you wait a bit to long and have to give it extra juice to get back up to that speed. It is far easier, and ultimately more consistently successful, just letting the cruise control do its job.

I have shifted our Bolt into neutral and back to D, while driving, just to see what it does. There is no clutch in the transfer case, only a bevel gear on the motor shaft, and another on the axle. Electric motors, with power to the motor windings, will produce back EMF when coasting. This is not as strong as active regen. If the motor is disconnected from the battery, it will spin like a simple flywheel with no back EMF. This appears to be what happens when you put the Bolt in neutral. Depressing the accelerator also shows no rise in power above the accessory load, and there is no hint of motor whine.

Relating to the subject of full charge miles: Today was the first time, in over 1,300 miles, we charged to 100% rather than 90%. The guess-o-meter read 287 miles.
 

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In theory there would be no downside to coasting down the hill, as long as you reapplied just the right amount of power, at just the right time as the car decelerates back to your chosen speed. In practice, this is extremely difficult. You either give it juice too soon, causing it to overshot your chosen speed unnecessarily, or you wait a bit to long and have to give it extra juice to get back up to that speed. It is far easier, and ultimately more consistently successful, just letting the cruise control do its job.

I have shifted our Bolt into neutral and back to D, while driving, just to see what it does. There is no clutch in the transfer case, only a bevel gear on the motor shaft, and another on the axle. Electric motors, with power to the motor windings, will produce back EMF when coasting. This is not as strong as active regen. If the motor is disconnected from the battery, it will spin like a simple flywheel with no back EMF. This appears to be what happens when you put the Bolt in neutral. Depressing the accelerator also shows no rise in power above the accessory load, and there is no hint of motor whine.

Relating to the subject of full charge miles: Today was the first time, in over 1,300 miles, we charged to 100% rather than 90%. The guess-o-meter read 287 miles.
Well practice is always harder than theory. You certainly should only do things you are comfortable with or feel safe doing. Saving energy doesn't mean much if you crash. My only point is that coasting and not expending energy is always going to be more efficient than using energy and trying to recapture energy. Making it happen in the Bolt just requires a little more work than an ICE car and the efficiency gains aren't as high in comparison. ICE cars are terribly inefficient at turning energy into motion so coasting in an ICE car offers higher efficiency returns than coasting in an electric car, but coasting in an electric car is still more efficient than spending energy to try and recapture energy.

My hesitation around shifting into neutral while driving is that I have seen reports of some Bolts doing weird things while in neutral, getting shift errors or just plain not being able to shift back into gear. In all my previous cars, manuals, I was in control of the mechanical components so I controlled when it did or did not go into gear (short of a transmission failure of course) but I felt in more control. With it being electronic control engaged, well I just feel less in control there. I'm sure I will overcome that concern over time as it is probably not an issue to worry about.
 

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In D or L, on hilly terrain, using cruise control, our Bolt maintains the set speed within plus or minus a mile an hour...better than any car we have owned. Unless you are driving in heavy traffic, driving the speed limit, or slightly less, in cruise control, will be the most efficient way to go. Coasting will not save energy. Rolling downhill at faster than your average speed, will raise your average speed, but do nothing to conserve battery energy.
If you're driving in gently rolling countryside where the road goes through a series of up and down undulations then you're better off without cruise control. It's more efficient to allow the vehicle to pick up speed on the downgrades so that its momentum will help to carry it through the upgrades.

If you use cruise control in that situation it will use regen to prevent the car from accelerating on the downgrades and then have to feed energy to the motor to maintain the speed on the upgrades. Since regen is considerably less than 100% efficient, that will waste energy.
 

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Sean Nelson,

"If you're driving in gently rolling countryside where the road goes through a series of up and down undulations then you're better off without cruise control. It's more efficient to allow the vehicle to pick up speed on the downgrades so that its momentum will help to carry it through the upgrades."

That might make sense somewhere with long straight roads. Here, the hills don't last for very long, and most have curves. Exceeding the speed limit, coasting into a blind curve with the frequent appearance of animals, down branches, or a texting SUV driver over the center line, doesn't make for relaxed driving.
 

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Sean Nelson,

"If you're driving in gently rolling countryside where the road goes through a series of up and down undulations then you're better off without cruise control. It's more efficient to allow the vehicle to pick up speed on the downgrades so that its momentum will help to carry it through the upgrades."

That might make sense somewhere with long straight roads. Here, the hills don't last for very long, and most have curves. Exceeding the speed limit, coasting into a blind curve with the frequent appearance of animals, down branches, or a texting SUV driver over the center line, doesn't make for relaxed driving.
Yes, but talking about what is most efficient doesn't mean it is the safest way to drive. You of course have to make that determination based on the current driving conditions.
 
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