152 mile range when fully charged?

[bolter]

I've had my 2017 Bolt EV Premier a little over a month, and it has 600 miles on it.

Right now, it is sitting in my closed-but-unheated garage plugged in. It says it is fully charged and that the range is 152 miles, only 64% of the claimed 238 miles. The car displays the ambient temperature as 45 F.

The energy screen says zero for other factors that affect range and -3.8 for outside temperature.
This seems like way more capacity loss than I would expect for this temperature. It seems like, if battery loses 1/3 of its capacity when the temperature drops to 45, it would become almost useless in really cold conditions.

Any ideas?

 

[iletric]

What was the ambient temp during charging?
-3.8 or 45?

 

[bolter]

It was never as low as 3.8. The -3.8 is the Outside temperature value shown on the Energy Usage Score page. See the attached photo. I don't know how cold it was in the garage while it was charging. It could have been as could as 20 or 25 F part of the time, but must have been 40 F or higher part of the time. However, I don't see how a low temperature while charging could decrease the amount of energy that would be available from the battery after it was warmer and still plugged in.

What mostly concerns me is the large decrease in range with a fairly modest decrease in ambient temperature.

 

[bolter]

Here's the pic . I forgot to attach it.

 

[SparkE]

There are quite a few "range question" posts (including temperature-specific issues) on this site. Your question(s) might already be answered.

 

[boltage]

In recent driving just before recharging, were you getting worse economy, commonly due to using the heater?

The bar graph of economy in 5 mile chunks may be a useful thing to look at.

 

[PackardV8]

Welcome to the real world of wintertime EV range.

We use hilltop charging and and at 20 degrees are seeing 140 miles or less.

jack vines

 

[LeftieBiker]

If I read that virtual gauge correctly (and I'm not sure I do) then the climate control is responsible for a lot of the drop. The heating system always eats huge amounts of power in an EV in frigid temps.

 

[WetEV]

The disadvantage to an EV is that you lose range. Sure, an ICE also loses range in cold weather, just not as drastically.

The advantage to an EV is that the car starts.

 

[GetOffYourGas]

The car starts, provides full power, instant heat to the driver, and actually saves even more money on fuel costs in the winter. EVs have a lot going for them in the cold, but most people are just taken aback by the drop in range.

 

[WetEV]

I should also mention the joy of never stopping at a gas station on a frigid day with a stiff wind blowing...

 

[bolter]

Let me emphasize that what surprised me was not that the range decreased in cold weather, but that the range decreased by so much, one third, with a temperature, 45 F, that's not even very cold. Also, as I understand it, the car actively heats and cools the battery as needed to keep it at the optimal temperature, so why isn't it, right now while plugged in, doing that and showing a longer range for its fully-charged battery?

 

[GetOffYourGas]

My understanding of the Bolt's battery heater is that its purpose is to protect the battery from damage, not "to keep it at the optimal temperature". I have never seen my Bolt heat the battery when it is that warm out. I've only noticed it kick in when the OAT dips below freezing.

Try driving without the heater on for a while and see what the car reports for expected range. I'm guessing it's much higher than 152 miles.

Speed also kills range. And cold air is denser, which makes the drag that much worse.

 

[oilerlord]

The car starts, provides full power, instant heat to the driver, and actually saves even more money on fuel costs in the winter.

Not sure I quite get where you're going with this, Brian. We can accept that an EV is dramatically less efficient in cold temperatures - and can take up to twice the number of kWh's to drive the same distance that it does in summer - so how does an EV save "even more money" in winter?

No doubt an EV still saves money (vs ICE) overall, but I buy a lot more kWh's in winter than I do in summer.

 

[GetOffYourGas]

The car starts, provides full power, instant heat to the driver, and actually saves even more money on fuel costs in the winter.

Not sure I quite get where you're going with this, Brian. We can accept that an EV is dramatically less efficient in cold temperatures - and can take up to twice the number of kWh's to drive the same distance that it does in summer - so how does an EV save "even more money" in winter?

No doubt an EV still saves money (vs ICE) overall, but I buy a lot more kWh's in winter than I do in summer.

Both EVs and ICEVs use more energy in the winter. On that we all agree.

The short answer is, although the percentage increase is greater in kWh versus gallons, kWhs cost a lot less than gallons and the numbers work out that the absolute cost of fuel increases more for gallons than for kWh. A small percentage of a large number versus a large percentage of a small number.

I wish I could find the study that was done a while ago, but it escapes me.

Let's just run somewhat fabricated numbers:
EV = 4 miles/kWh summer, 2 miles/kWh winter. $0.12/kWh.
ICEV = 35 MPG summer, 25 MPG winter. $3/gallon.

EV = $0.03/mile summer / $0.06/mile winter
ICEV = $0.086/mile summer / $0.12/mile winter

EV savings = $0.056/mile summer / $0.06/mile winter.

Obviously more expensive gas tips it more in the EV's favor as always. The study I'm thinking of was done when gas prices were more like $4/gallon. So maybe with current prices it's more of a wash.

 

[SeanNelson]

The energy screen says zero for other factors that affect range and -3.8 for outside temperature.

The reason it says that is because you've just finished fully charging the vehicle. It doesn't matter how wildly you drove or how high you had the heater on the last time you drove it, those figures were all reset by the full charge. So the screen you showed provides no useful information about things like terrain, climate usage or your driving style.

My experience here in Vancouver BC where the temperatures are around 0 to 5C (32 to 40-ish F) is that almost all of the range reduction is due to heater use. I've bundled up warmly and driven around with the HVAC heater turned off and using only the heated seats and steering wheel, and I'm getting in the 13 to 14 kWh/100km range, and that's going up and down some pretty significant hills. That's better than the EPA rating, which is about 15.7 kWh/100km. But when I use the heater consumption jumps up to the 20 to 25 kWh / 100km range, almost twice as much.

I'd suggest trying a drive without running the heater and see how well you do.

 

[oilerlord]

Both EVs and ICEVs use more energy in the winter. On that we all agree.

The short answer is, although the percentage increase is greater in kWh versus gallons, kWhs cost a lot less than gallons and the numbers work out that the absolute cost of fuel increases more for gallons than for kWh. A small percentage of a large number versus a large percentage of a small number.

I see where you're coming from. Makes sense. I guess that now that I've been driving an EV for a while; I'm not comparing the cost of electrons against the price of gasoline as much as I used to. My "absolute" cost of driving the EV goes up in winter because I have to charge more often to drive the same distance I do in summer.

 

[desiv]

I agree, that seems low..
I have more than that on my car every morning, and we've been having 40ish degree weather here (some 30's and a small bit upper 20's) the last few weeks, and I use Hilltop.
Never less than 160 in the morning. (and that's with Hilltop enabled, so 90-ish%)

I use heat the whole time for my drives (set at 71).
My driving is mostly highway (60-65).

What are your driving style/speeds?

One thing that I do is that I preheat the car while plugged in the morning... So most of the energy to initially heat the car doesn't come from the battery pack.

Also, what is your average miles per kW? I'm around 3.1 or so usually.

desiv

 

[Chargeit]

We just bought our 3rd Chevy EV, and the Guess-o-meter on the dash will drive you crazy if you let it. My wife is all freaked out because her new Bolt only shows 148 miles when she thought it should read 238. When I checked her Energy Score, it shows positive numbers for Technique and Terrain, and -5.0 for both Outside Temperature and Climate Settings. It doesn't help that it's only 20 degrees outside.

A better gauge of your range is the Energy Used dial. If you get to your destination and have used less than 50% of your battery capacity, you have enough to get back. If not, drive slowly and turn the heater or AC off. The battery conditioning comes on automatically when it's below freezing, so controlling that variable is not an option.

Driver technique has a lot to do with what the Guess-o-meter spits out. My daughter and I have two identical Spark EVs, and when we got them, they both showed 82 miles of estimated range. After a couple months, hers was consistently reading over a 100 and mine was down in the 70s. It had my number. My wife doesn't even like me driving her car because she thinks I'll mess up her range, too. I've given up trying to explain...

The best way to improve your technique is watch your acceleration. If you can keep it under 30kW (20kW for the Spark) you're doing OK. But it isn't possible once you get on the freeway and up to speed. Oh yeah, and watch braking. Actually engaging the physical brakes is unnecessary with the Bolt if you keep your distance and anticipate your stops.

 

[LeftieBiker]

Let me emphasize that what surprised me was not that the range decreased in cold weather, but that the range decreased by so much, one third, with a temperature, 45 F, that's not even very cold.

This is the biggest argument for having a heat pump in your EV. From whatever temp you start using heat (or even just defog in cool weather) down to roughly Freezing, the heat pump will minimize the reduction in range. When temps are in the forties it's no worse than turning on the A/C on an 80 degree day.