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Discussion Starter #1
I charged to full last night for the first time (no hilltop reserve). Estimate said 260 miles this a.m. "kwH used" screen said 0 kwH, 0 miles.
Then downhill 750 ft in 2 miles. At bottom: kwH used said 0. The miles estimate was up to 268.
The green lightning bolt read about 1-2 kWh on the way down. The regen icon was white, indicating no regen. The paddle on the steering wheel did nothing.
We did not try gear "L".

So what is going on? The 1-2 kWh could mean that some energy is being used because the car is on, and that is being replaced.
The 0 kWh used or saved indicates, maybe, that 0 kWh were being stored on descent. Generally it subtract, but it might not like negative numbers, or it might not be storing, since full.

These facts are consistent with the battery being unavailable to the user (even if it is not strictly full, as some think (and other don't)). That is why it has Hilltop Reserve in the first place! But why would the 260 jump to 268?

We are gearing up for a trip to Denver in 2 days (130 miles round trip, 12000 ft total climb, 12000 descent) and are hoping to do it on a full charge with no charging en route. Since 130 is half of 260, that seems fully possible.
 

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The estimate of 260 miles is based on your passed drives and an estimate again. The car could go over 300 miles in right conditions.

So the car jumped to 268 because it realized it was not using any kWh and thinks you are going to keep driving downhill, thus thinking it can go 268 miles if the road stays the same.

I would recommend driving in "L" mode down hill and using hilltop reserve since you say the first 2 miles are downhill, also read its better for the battery.

As far as making to denver and back on a full charge seems feasible if it is only 130 miles. That is assuming 260 estimate is with heater/ac on, and take into consideration the ambient temperature in colorado could use some of the battery also.
 

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Discussion Starter #3
Thanks. Seems logical. I have not been using the air heater. Just the seat heater rarely. Ambient temps here these days are 30-50 F. I suppose that is considered cold: I am getting a negative temp score on that window even if it just sits in the garage overnight at 50 degs. Anyway, the Denver drive should work. So far on every trip the increase in miles driven is quite a bit greater than the decrease in predicted miles. I imagine that will even out over time (we have done 500 miles). I also note that 0% has been used for "battery conditioning". I am not 100% sure what that is.
 

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I also note that 0% has been used for "battery conditioning". I am not 100% sure what that is.
Battery Conditioning is when the battery is too cold, or too hot, to be used. So the car has a secondary heating/cooling system just for the battery (not for the passenger cabin). That rating is how much energy is being spent to keep the battery in a usable range.
 

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I'd plan to charge in Denver. 260 may be plausible but for sure I'd get serious range anxiety throughout making that attempt. Especially on hilly/mountainous terrain. Regen going down a hill doesn't give nearly as much juice as will be required to go up the same hill. And I've found the battery likes ambient temp of more like 80F-90F you get a negative climate score if your outside temp is below that. Then there's the wind. Its likely you'll be facing a headwind on the way back... same kind of problem as hilly terrain, its great getting regen kind of effect with tailwind but you'll pay dearly in headwind.

I'd preplan to find a place where as a minimum you can leave the vehicle plugged in with the 120v trickle cord at 12A setting. For at least several hours. Or if vehicle is equipped DC fast charging, certainly hit one of those.
 

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Discussion Starter #6
Thanks cehjun. Your comments are welcome. Needless to say, running out is not something we want to experience.

1. There is a chargePoint station halfway down. So we can stop at that on way up (or down, I guess) if anxious. (yes, we have DC charging, but typical ChargePoints do not offer that).

2. On the way up from dealer (65 mi) we averaged 3.7. Call it 3 to be ultra conservative since we would have gained a lot on the descent from 11100 Ike tunnel to town at 8750. 65 miles divided by 3 is 21.7, so it would appear that we used WAY under half capacity for the serious climb up from town. Things will be a lot different going down. So I have a hard time seeing how I can use 60-kWh for the down and up. But of course, we will watch the numbers very carefully.

Here's a new cool thing: When I leave my house with a full charge, I go down 750 ft, and there is no regen. Using L or the paddle does nothing. So I might as well blast the heat full blast for this downhill 2 miles to get some warmth in the car, and perhaps some regen as well. This is a good reason to start with a full charge, at least in winter, tho I realize that using HilltopReserve is generally a good idea.
 

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Discussion Starter #7
And I think someone asked this on this thread: Going downhill this a.m. after full charge: the regen paddle, and also putting it in L do nothing. It seems clear the tank is full, though the lightning bolt can be very lightly green: 1-2 kw.

Wow: Chevy/OnStar just sent me this:

Get 5¢/gal off at Shell when you sign up for the Fuel Rewards® program. You can find this offer and more when you use AtYourService in your vehicle (if available) or mobile app.

I replied, asking them what I would use this for exactly?
 

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Sorry stanwagon. I just re-read the updates to this thread including post #1 . Realized I got confused (happens easily) in thinking that Denver and back is 260 mi round trip for you ! and not 130 round trip. Thus my dumb answer in post #5 .

130 down and up ? Yeah I'd give it a shot. What the heck, in the unlikely event you coast to a stop (be careful).
Just call Roadside (free coverage for 5 years) and make sure they send a truck with a big generator on it. I know that the manual says don't plug your 120 trickle cord into a generator. But I doubt it would do any harm. Perhaps one of the engineers on this forum is an electrical engineer and could clarify... sine wave stuff ?
 

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Discussion Starter #9
Thanks Cehjun. My wife has been stressing out over this. I called ChargePoint to make sure my account was up to date, just in case. But it seems to be hard to pay for fuel here. Local WholeFoods has a ChargePoint -- it is free. There is one halfway to Denver by a restaurant. It is free.

I am going to run my phone GPS app to get the total climb, which I estimate at 13000 feet. Wow, that is 100 feet per mile, which is pretty much what a typical hilly cross-country ski course is.

And thanks for the tip about Roadside.

Let me report here what Sean Nelson said on another thread. When on rolling terrain and trying to get back up to speed (with no energy expenditure) at the crest of a hill and starting down the downhill side, just hold the acc. pedal down so that charging is close to 0. That will simulate Neutral. This sounds very logical and I will try it, since I am always discouraged from putting it into N to do this.

Anyway, this is all great fun! Something else I realized yesterday is that when starting with a full charge and heading down my 750 foot hill I may as well turn all heaters on full, since there is no regen if I don't and this will perhaps give a little regen, and also warm the car more or less for free.
 

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Anyway, this is all great fun! Something else I realized yesterday is that when starting with a full charge and heading down my 750 foot hill I may as well turn all heaters on full, since there is no regen if I don't and this will perhaps give a little regen, and also warm the car more or less for free.
Just as a rough guess: Before setting off with battery full. Unplug vehicle. Try Preconditioning on the myChevrolet app 20 minutes before departure. Advantage: vehicle is nice'n toasty with clear windows when you initially climb in. AND when you get to the bottom of the hill the battery is again full ?

I'd like to see if I can change the Preconditioning settings. That is, which equipment gets turned on. Recently I noticed it turned on the rear defroster (hadn't seen that before when the weather was warmer). I don't need rear defroster.

Yes it's all great fun.
 

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Discussion Starter #11
Yes, I see the point. I do not have that app. Does it work from an iPhone without the need of the OnStar technology -- which I do not want to subscribe to.
 

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Yes, I see the point. I do not have that app. Does it work from an iPhone without the need of the OnStar technology -- which I do not want to subscribe to.
Yes. I let my Onstar expire after the free first six months bells-and-whistles plan. It defaults to Onstar "basic" which is free for 5 years. Now when I use myChevrolet app I get prompted for my Onstar password but after that the Preconditioning works fine.
 

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stanwagon,

My suggestion, for your trip, is that if you aren't seeing the mi/kWh you need, using your coasting technique, put it in cruise control, lower or turn off the heat, and keep reducing the cruise control speed setting, until you see your mi/kWh going up. Playing pinball wizard with the accelerator, with your family in the car, is not good for marital relations.
 

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Discussion Starter #15
Got to Denver and back (122 miles; 12000-13000 ft of climb) with 29 kWh total, less than 50%. Drove normally. 5.7 kWh to the 11100 ft tunnel 10 miles away (from 8700 start). Then only 2.3 kwH for the next FIFTY MILES. So about 8 total to get down. 21 to get back. So 29, means about $2.90 in elec. cost, about a gallon of gas for the 122 miles. Nice. No heat used. Lights on.

The bar chart of course is nonsense. It tops out at 252 no matter what. But in fact the true number for a 5-mile down stretch should be negative. And the average listed is even worse. Still no word from GM as to what they are trying to communicate there.
 

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I think that’s one special Bolt EV you’ve got. Other than the thin air up there I can’t think of a reason yours beats mine so significantly. (are the highways cement or asphalt?) (do cooler tires run more efficiently?) I thought my summer conditions were much more favorable battery-environment-wise and terrain-wise:

My typical trip numbers from the summer in following conditions : Flat paved divided highway in daylight, light traffic, 115 km/hr on cruise control (~70 mph), ambient temp 80F, each tire bang on 270kpa cold (39 psi), light wind, air/heat control turned off just 1-bar of manual fan outside air blowing in, iphone plugged in, vehicle otherwise empty:

I got 17-18 kWh/100km in other words: about 3.5-3.6 miles per kWh, about 10% worse than EPA estimate. Not even close to the 4.2 average you got on that 122 miles of rollercoaster !
 

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Discussion Starter #17 (Edited)
Can't explain it. But those numbers were solid. 70 mph for extended periods is likely a lot worse than my roughly 63. Also the air resistance here is a LOT less. That can have an impact. [[Edit: I see you noted that. 70% here at 9500 compared to sea level air drag]]

Roads here are typical US freeway; not concrete. But it might well me that monster hills are helpful (like 11100 down to 5200). Up here I am just not driving at highway speeds, so the 4.1 or 4.2 I am getting here is not comparable to what you are doing at all.
 
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