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What is the ambient temperature for the test? Temperature affects the air density and also determines the efficiency of the battery chemistry and if the battery needs to be heated. Is the Bolt washed and clean? A clean vehicle has a surprising effect on efficiency. What is the tire pressure? How many passengers? The total vehicle load of passengers and cargo will have a small but measurable impact on range.

There is no such thing as 200+ mile flat road.
 

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Best case is that at a constant 65 mph the Bolt would meet or slightly exceed its estimated 238 mile range. It is just my guess but the real world range at 65 mph would probably be 15% less than the estimated 238 miles, so ~202 miles. You have to consider the temperature because it has a marked impact on battery efficiency and range. At very low temperatures this can result in a 25% or more reduction in range. You would not be very comfortable driving 200+ miles in a Bolt with the climate control turned off with an outside temperature of 85 - 95 F but the Bolt's battery would be operating at near peak efficiency. At 65 - 75 F you would be more comfortable but the Bolt's battery would be operating slightly less efficiently. As the temperature drops so would the battery efficiency and range. When the temperature drops below ~ 60F the Bolt's battery pack will be heated, this saps additional power from the battery contributing further to reduced EV range.
 

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Discussion Starter #6
Ok. On my 2017 Volt I get a little better than the EPA rated 53 mile range. Is the Bolt more aerodynamic than the Volt or does it normally get more miles per kWh?
 

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There is no such thing as 200+ mile flat road.
West Texas? :) I seem to remember the 223 miles of US 287 between Amarillo and Wichita Falls to be very flat and open.

Actually I consider anything east of I-25 in Colorado to be flat. Compared to the 6 to 10 thousand foot elevation difference between east and central Colorado everything east of I-25 is flat.
 

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Ok. On my 2017 Volt I get a little better than the EPA rated 53 mile range. Is the Bolt more aerodynamic than the Volt or does it normally get more miles per kWh?
The Bolt (with a coefficient of drag of [Corrected 0.308 cd]) is actually less aerodynamic than the Volt (0.285 cd). However, the Bolt's electric drive is more efficient with an EPA rated range of 238 miles, this equates to ~ 4 mi/kwh. For the Volt's EPA EV range of 53 miles it is ~3.76 mi/kwh.
 

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Once they start putting DCFC's on Interstate 5 going through the Central Valley of California I would expect to go 250 miles at a cruise controlled rate of 65 MPH in the right lane. I would expect to lose 6% of that with the A/C on.

In real life, though, I would expect to only be able to do 60 MPH in the right lane due to the trucks which have a speed limit of 55 but tend to go 60, so my my mileage would go up.

The left lane is a "no holds barred type of situation" and I do not want to waste my battery at those speeds until I know how far the next DCFC is.
 

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The Bolt (with a coefficient of drag of 0.32 cd) is actually less aerodynamic than the Volt (0.285 cd). However, the Bolt's electric drive is more efficient with an EPA rated range of 238 miles, this equates to ~ 4 mi/kwh. For the Volt's EPA EV range of 53 miles it is ~3.76 mi/kwh.
The cd for the Bolt is .308. The .32 figure was an engineering goal GM exceeded.
 

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The EPA highway figure is generally accurate for cruising at 65 mph. Shouldn't be hard to hit 217 miles. For buying a vehicle, your typical drive should be no more than 50% of rated vehicle range, or less in a cold climate. I.e., if you commute 100 miles per charging opportunity, a range of 200 miles is good. A range of 125 miles is not enough. Weather, (a 30 mile per hour headwind could reduce range dramatically at higher speeds), traffic emergencies, battery aging, etc.
 

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The EPA highway figure is generally accurate for cruising at 65 mph. Shouldn't be hard to hit 217 miles.
Right. The highway EPA-rated range is 217 miles, not 238. 238 is the combined cycle range.

I would guess you could get close to that in ideal conditions. But that's all it is, a guess. Until someone does multiple real-world tests, it appears that's all we've got.
 

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Right. The highway EPA-rated range is 217 miles, not 238. 238 is the combined cycle range.

I would guess you could get close to that in ideal conditions. But that's all it is, a guess. Until someone does multiple real-world tests, it appears that's all we've got.
The latest 5 cycle test from the EPA is less than ideal. I would expect under ideal conditions the Bolt EV should be able to do more than 217 miles at 65mph. In fact if I had to guess. Considering that many people are getting over 300 miles I would presume more than 250 is likely possible at 65mph.
 

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Car and Driver got 190 miles of range in the Bolt running at 75 mph in the California mountains with the A/C set to 72 degrees.
And it's important to note that battery power consumption is not linear with speed. It takes a lot more power to cruise at 75mph than it does at 65mph because there's 33% more aerodynamic drag even though you're only going 15% faster. That's because aerodynamic drag increases with the square of the speed.
 

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No HVAC, no wind, no fast acceleration, flat road - What's the consensus on the range with the battery fully charged?
My testing, corrected to 600' elevation and 70 deg F, shows that the range at a constant 65 mph is 239 miles.

I calculated the EPA combined range match point to be a constant 65.2 mph.
 

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There is no such thing as 200+ mile flat road.
Try driving through Kansas. But I would love to see some independent testing done on a big track like Indy. They could run fully charged Bolts at various speeds and see what they get. Of course this would be for fun, but maybe they could run a Tesla along side and see how efficient each vehicle is at various speeds.
 

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OK 200 miles and then ?...Where to charge ?...The BOLT is a commuter car until GM resolves the fast charging network!!!. Do not hold your breath.
 

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OK 200 miles and then ?...Where to charge ?...The BOLT is a commuter car until GM resolves the fast charging network!!!. Do not hold your breath.
Exactly what I wanted, a commuter cat that can travel the greater Chicago metro area without fear of running out. No need to hold my breath, I have no plans on taking my Bolt EV cross country. But if I wanted to travel those distances, I'd take my Volt. :)
 
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