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Hello all ,
Quick question
after 2000 mi of battery usage , I am showing avg 5.5 mi per kWh
I owned a fiat 500e that avg 4.4 mi per kwh
I’m hearing Tesla’s run around 4.3
Could it really be that efficient ?
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If you’re tires are OEM Goodyear and blown up to about 45psi. Your driving very conservatively, with the wind, downhill, and no faster than 45.
 

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My lifetime average in my 2014 is 4.4 mi/kWh with 145k miles on the odometer. That's 39K miles pure electric and 107k miles on the generator. You are doing very well!
 

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Without using a calculator, it looks like you got close to 6 mi/kW-h (!). Good job. It all depends on the conditions. I can get over 8 mi/kW-h on my way to work (800' elevation drop) over 10.5 miles, but the trip back up the hill requires nearly 4 kW-h. In general at lower speeds and minimal HVAC use, I will tend to see about 4.5 mi/kW-h on average.

Keep up the good driving habits!
 

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I calculate my energy usage based on how much I put IN, not on the display of how much comes OUT, of the battery. Since I pay for what I put in, that's more important to me.
27,000 miles of electric on 8657 kWh works to 3.12 m/kWh. The charger is about 85% efficient (240v, about 80% on 120v) that would be somewhere around 3.6 to 3.7 m/kWh per the dash display.
I've recently switched to some new-to-me, nearly new, used tires and have noticed a big improvement in efficiency. Still too early to claim any definitive conclusion. My rolling average for the last 10 calculations (weekly) show me at 4.18 m/kWh input (about equivalent to 4.9 m/kwh dash display of output). My last 5 weekly entries are at 4.76 miles per kWh of grid power purchased.
This time of year is usually peak season: cool enough so no A/C, warm enough so no heat or defrost. Still, October 2020 was 3.7 mi per kWh in, October 2019 was 3.8, October 2018 was 3.4, so the difference this year compared to those is substantial.

p.s.: 5,600 miles on gasoline, 156 gallons (37.9 mpg, or 6.2l / 100km)
 

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Hello all ,
Quick question
after 2000 mi of battery usage , I am showing avg 5.5 mi per kWh
I owned a fiat 500e that avg 4.4 mi per kwh
I’m hearing Tesla’s run around 4.3
Could it really be that efficient ?
What about any regen you used to drive those 50.8 electric miles?

Did you not slow down using the regenerative brakes, and then use that regen when you accelerated back up to speed? Did you at some point drive down a long hill, putting downhill regen into the battery (did you see the kWh Used decrease as you drove because of this?), and when you reached the bottom, did you not then drive on regen battery power to add a certain amount of electric miles to the total?

So, how much fuel did you use to drive those 50.8 electric miles? The display shows 8.5 kWh of grid power, but it doesn’t show the amount of regen you used... Was the route on flat ground? Did it include downhill driving? We don’t really have any display showing Regen Used during Electric Mode or Extended Range Mode driving, although it’s probably safe to say that grid and regen power have the same "energy content," and are equally efficient as fuel for electric driving...

Can you really calculate your Volt driving efficiency if you don’t include the amount of regen battery power that contributed to the total Electric Miles?
 

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Yes, one can. Whether the miles per kWh going uphill or during acceleration were higher than the m/kWh slowing or going back down doesn't matter. The total miles traveled and the total power out of the battery allow calculation.
Regenerated electricity isn't free. It comes from a loss of altitude and/or velocity either or both of which are obtained by driving upward or speeding up. The 'return' of electric power from regen is from the prior expenditure of energy. The display shows the sum of expenditure and return. Since neither in this instance were obtained from gasoline (see the embedded image in the original post) and presumably not obtained from pushing or towing the Volt, the logical (to me, anyway) conclusion is that the 50.8 miles were all battery powered.

What IS unknown is the starting altitude and what was the energy consumption rate to drive UP to that hilltop charging point.
It's also not known if the car might have been up on jack stands and spinning the wheels with no air drag and no hills, but that's just an internet conspiracy...
 

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I calculate my energy usage based on how much I put IN, not on the display of how much comes OUT, of the battery. Since I pay for what I put in, that's more important to me.
OTOH, the "out" vs "in" proportion is something that's neither changing nor controllable. So the "out" is a valid proxy for "in" unless you think there's electricity evaporating from a puddle in the low spots of the battery housing...
 

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Tesla's best stated efficiency is around 4 miles per Kwh where as Lucid's is around 4.5/4.7 miles per Kwh. and they make much of the fact that their car is so much more efficient than a Tesla. These are hard fought efficiencies using the latest technology so a ten year old technology is not going to best them so that 5.5 miles per Kwh has to come from some other means, some possibilities have already been mentioned.
 

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Yes, one can. Whether the miles per kWh going uphill or during acceleration were higher than the m/kWh slowing or going back down doesn't matter. The total miles traveled and the total power out of the battery allow calculation.
Regenerated electricity isn't free. It comes from a loss of altitude and/or velocity either or both of which are obtained by driving upward or speeding up. The 'return' of electric power from regen is from the prior expenditure of energy. The display shows the sum of expenditure and return. Since neither in this instance were obtained from gasoline (see the embedded image in the original post) and presumably not obtained from pushing or towing the Volt, the logical (to me, anyway) conclusion is that the 50.8 miles were all battery powered.
I agree, the OP’s 50.8 electric miles were all battery powered... but what was the "total power out of the battery" that he used to drive those 50.8 electric miles? I suggest it was more than 8.5 kWh.

Let’s say the OP started driving using 0.4 kWh of grid power for acceleration to a given speed. Light turns red, Volt comes to a stop, recapturing 0.3 kWh of that energy used for acceleration. Light turns green, Volt again uses 0.4 kWh of battery power to accelerate to that given speed.

Total power used for acceleration = 0.8 kWh
Total power used for acceleration that is shown on the energy usage display screen
= 0.4 kWh grid power used (- 0.3 kWh regen put into battery + 0.3 kWh regen power used) + 0.1 kWh grid power used = 0.5 kWh total used

Seems to me the OP used 8.5 kWh of grid power plus an unknown amount of kWh of regen to drive 50.8 electric miles. Level terrain regenerative braking would have increased the total kWh used for the driving. Volt drivers really have no display that shows the regen kWh Used during a trip.

Non-level regen is a bit more complex, but the same principle applies. A portion of the grid energy used to increase the elevation of the car is converted into gravitational potential (note that driving uphill has both horizontal and vertical components, so not all the kWh Used to drive uphill is used for the change in elevation). On the way downhill, it’s the force of gravity, not grid power, that may accelerate the car downhill or merely maintain the speed (i.e., in a sense, that amount of power gets used twice). If the brakes are applied while driving downhill (e.g., using L to maintain a cruise-controlled speed), that’s regen into the battery, which is reused when you’re back on level terrain. Again, a portion of the grid power used to move the car to a higher elevation is captured and used a second time to drive electric miles without increasing the net kWh Used.

Can you really calculate your Volt driving efficiency if you don’t account for the regen battery power that contributed to the total Electric Miles?
 

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Do you want total power out of the battery, separate and without the total power regeneration put back into the battery?
I don't know if the Volt is able to list power out separate from regen power back in. There's just the one net sum of all the minuses of kWh used for acceleration and air resistance and the few brief plusses of regeneration, all rolled up into one total: 8.5 kWh in the original poster's image.
That 8.5 kWh IS the amount of grid power. Whatever regeneration power was created from losing altitude and/or inertia was previously created from EXTRA consumption of grid power to gain altitude and/or momentum. The regeneration power quantity, what ever was accumulated, wasn't 'free'. It was purchased from the grid, 'banked' in the battery, 'spent' at a higher rate, then partially 'harvested'. It's still grid power.
 

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re: Tesla and Lucid stated operating efficiencies. Auto manufacturers have defined driving programs they must follow so that they use exactly the same driving program as the other manufacturers. This allows you and I to compare some vehicle's result against some other vehicle's result.
I'm not a manufacturer. I don't have a defined E.P.A. driving program of set acceleration, speed, braking, and distance.
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Do you want total power out of the battery, separate and without the total power regeneration put back into the battery?
Yes, I want to know how much power the motor used to propel the car those 50.8 ev miles. As you drive, the motor uses grid power from the battery to accelerate and to maintain speed, then some driving condition requires the car to slow, so the car’s kinetic energy is used to crank a generator, slowing the car down and putting power into the battery, and then the motor uses that regen as fuel, too. Efficiency should be a measure of distance driven using both that grid and that regen power. I agree that 8.5 kWh IS the amount of grid power used at that point in time, but "the regeneration power quantity, what ever was accumulated," was also used by the motor to propel the car those 50.8 ev miles. How much total power did the motor use? I don’t think we know how to calculate that number.

Then again, "efficiency" is such a loosely defined concept here... seems odd that "efficiency" could be impacted by the clothes you wear while driving... wearing a warmer coat in the winter or shorts in the summer instead of cranking up the heat or air conditioning would help minimize the power consumption used for climate control, leaving more of the full charge for use as motor fuel to extend the ev range.
 
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