Two good trips today. Avg Wh/mi 350ish

[a.void]

As others have stated, I've been seeing 65-70% efficiency with the cooler temperatures.

This morning, I had a good opportunity to really test with a 61 mile each way, roundtrip.

Tezlab reports added.
The battery was fully warmed within about the first 25 minutes (no Regen dots)
That is where I fail to understand why the inefficiency. I understand if the battery is cold we'll have inefficiency, but if the battery is fully warmed up, then shouldn't we see much better efficiency regardless of outside temperature?

 

[juliusa]

Even after the battery and cabin are warm, cold temperatures still require energy to heat the cabin and in some cases the battery - so your wh/mi will continue to be higher.

Also, I don't think the higher wh/mi is because of lower efficiency of a cold battery - I think it is because of the energy used to heat the cabin and battery.

 

[TexasEV]

Don’t forget that ALL cars use more energy in the cold, as cold air is denser than warm air so it takes more energy to push through it.

 

[coleAK]

In our LR AWD 3, What I’ve realized on energy usage so far, I’m in Alaska. Driving around town (Anchorage) that is never over 55 mph and no stop and go traffic prior to snow on the ground I was 320-330 Wh/mi. Now that we have cold and snow/ice covered roads I’m at 368 Wh/mi average over the last 3 weeks. The heater does effect this, but electric heaters are inefficient, high electricity consumers and how else would an electric car heat itself? Another large factor is going uphill, I think these vehicles lose much more efficiency under increased load than ICE. I live ~1000 vertical feet above the city so go down and up every day. I’m in the 600-900 Wh/mi going up the hill which is over 4.5 miles and has a max of 25% grade, with a 40-45 mph speed limit. Yes all vehicles use more energy going up hill but not nessisserly 3x more. I do get some of that back going downhill but I’ve tried it and if I go down turn around and go back up I average >400 Wh/mi. Also to back up my theory of more use under load. I have a buddy with an X that pulls an rPod (camper). He can only go 80 miles when towing, a ~70% efficiency reduction. Where as I get more like a 50% effenciency reduction pulling my camper with my ICE.

I have some additional thoughts, why is everyone so hung up on this? All the forums are full of posts about efficiency and most people are complaining about ~10-15% worse than rated. Did your ICE get the exact EPA mpg? We are going into winter in much of the USA, vehicles always are less efficient in winter driving. All my vehicles have always gotten 25-33% worse fuel economy in the winter, why should the Tesla be any different? Also another factor is these things accelerate fast. If you are taking advantage of this you are consuming much more electricity. Just stomp the accelerator and watch the graph. I’ve done the math and given the low drag coef and small frontal area the difference in 55 mph and 65 mph is almost nothing, and as long as you keep it under 70 drag should be a small factor. And you refuel your car every night at home for way less cost per mile than any other vehicle.

Finally is it just because the Tesla gives us so much more information that people are getting hung up on it? Searously I’ve been active on the land cruiser and Porsche forms for years and efficiency rarely ever is mentioned. Land cruisers are notorious for terrable gas milage and no one is on those forums talking about the fact we get 12 MPG instead of 16 mpg. And yes I do feel bad about getting 12 mpg but as soon as Tesla (or someone else) builds a body on double box frame SUV with extremely strong off road ability that can tow 8000 lbs I will get rid of my 200 series LX.

 

[AWDtsla]

The battery was fully warmed within about the first 25 minutes (no Regen dots)

That's not even close to "fully warm"


350 is amazing. I've been getting 450ish last 2 days in my S.

Need a heat pump to get better numbers in the winter.

 

[swaltner]

In our LR AWD 3, What I’ve realized on energy usage so far, I’m in Alaska. Driving around town (Anchorage) that is never over 55 mph and no stop and go traffic prior to snow on the ground I was 320-330 Wh/mi. Now that we have cold and snow/ice covered roads I’m at 368 Wh/mi average over the last 3 weeks. The heater does effect this, but electric heaters are inefficient, high electricity consumers and how else would an electric car heat itself? Another large factor is going uphill, I think these vehicles lose much more efficiency under increased load than ICE. I live ~1000 vertical feet above the city so go down and up every day. I’m in the 600-900 Wh/mi going up the hill which is over 4.5 miles and has a max of 25% grade, with a 40-45 mph speed limit. Yes all vehicles use more energy going up hill but not nessisserly 3x more. I do get some of that back going downhill but I’ve tried it and if I go down turn around and go back up I average >400 Wh/mi. Also to back up my theory of more use under load. I have a buddy with an X that pulls an rPod (camper). He can only go 80 miles when towing, a ~70% efficiency reduction. Where as I get more like a 50% efficiency reduction pulling my camper with my ICE.

Let's run the numbers to see what's going on here with your 1000' vertical delta between home and the nearby city.

The Model 3 has an empty weight of 4,000 pounds. Put 500 pounds of people and stuff in it and it's now sitting at 4,500 pounds (2040 kg). 1,000' of height difference is 304 meters. The potential energy difference between those two elevations is: 2200 kg * 9.8 m/s2 * 304 m / 3,600,000 Joules/kWh = 1.82 kWh. This is why the general rule of thumb is that you spend 7 miles of range to climb 1000' of altitude.

The EPA rated range on my Model 3 is at something like 240 Wh/mile. I question if it's really a 25% grade, but a 25% grade says your 1000' climb/descent is happening over the course of 4123' or .8 miles. That means you're spending 240 Wh/mile to move (the air out of your way) and 2,275 Wh per mile to climb the hill. You're spending almost 10 times your normal energy budget to counteract gravity. Even if the grade was a more reasonable 10%, that's still a 1000' climb over 10,000' (1.89 miles), which works out to 963 Wh/mile.

Do the same thing in a gas car that gets 30 mpg. A gallon of gasoline is equivalent to 33.41 kWh, so that works out to 1,113 Wh/mile. The same 2,275 Wh per mile to climb the hill is going to be consumed in addition to your normal energy needs, but that's a much lower percentage hit because your efficiency is so much lower to start with.

The same thing happens when you try to tow a trailer at speed (basically acts as a giant parachute adding drag). If your tow vehicle (my 2013 1/2 ton pickup) gets 15 mpg (2,227 Wh/mile) to start with, you're not going to notice the added drag from the trailer as much as when you start with an efficient vehicle like the Model X at ~330 Wh/mile.

And yes, what I believe is misplaced concern over minute changes in efficiency is because the cars are so efficient to begin with and you are given tools that show you the minutia of any slight variation due to weather and or road conditions. Using these same calculations, a 2.5% grade is enough to double your power consumption at highway speeds. Looking at List of mountain passes in Colorado - Wikipedia, every one of the mountain passes listed with a max grade peaks at over 2.5%.

Edit: And to make this relative to the OP, the same energy increase happens in cold weather on gas and electric cars, it's just that the percentage change is a lot higher on the EV since you're so efficient in "normal" operations.

 

[coleAK]

Nice I did the math to figure out speeds effect of range on another thread. On my hill the max is 25%. The average is ~5%. Its ~4 miles as the crow flys (closer to 5 miles driving it) and ~1000 vertical feet so 1000/21120 = 4.7%

 

[Ciditad]

I'm in Bmore and while the temperature hasn't been very cold, I do run heat and seat heater in 30s to 40s outside temperature. I noticed my consumption went from 235 or so to 250 or so when the weather got cooler. I hope l won't see consumption in the three hundred watt per mile.

 

[3Twin]

Let's run the numbers to see what's going on here with your 1000' vertical delta between home and the nearby city.

The Model 3 has an empty weight of 4,000 pounds. Put 500 pounds of people and stuff in it and it's now sitting at 4,500 pounds (2040 kg). 1,000' of height difference is 304 meters. The potential energy difference between those two elevations is: 2200 kg * 9.8 m/s2 * 304 m / 3,600,000 Joules/kWh = 1.82 kWh. This is why the general rule of thumb is that you spend 7 miles of range to climb 1000' of altitude.

The EPA rated range on my Model 3 is at something like 240 Wh/mile. I question if it's really a 25% grade, but a 25% grade says your 1000' climb/descent is happening over the course of 4123' or .8 miles. That means you're spending 240 Wh/mile to move (the air out of your way) and 2,275 Wh per mile to climb the hill. You're spending almost 10 times your normal energy budget to counteract gravity. Even if the grade was a more reasonable 10%, that's still a 1000' climb over 10,000' (1.89 miles), which works out to 963 Wh/mile.

Do the same thing in a gas car that gets 30 mpg. A gallon of gasoline is equivalent to 33.41 kWh, so that works out to 1,113 Wh/mile. The same 2,275 Wh per mile to climb the hill is going to be consumed in addition to your normal energy needs, but that's a much lower percentage hit because your efficiency is so much lower to start with.

The same thing happens when you try to tow a trailer at speed (basically acts as a giant parachute adding drag). If your tow vehicle (my 2013 1/2 ton pickup) gets 15 mpg (2,227 Wh/mile) to start with, you're not going to notice the added drag from the trailer as much as when you start with an efficient vehicle like the Model X at ~330 Wh/mile.

And yes, what I believe is misplaced concern over minute changes in efficiency is because the cars are so efficient to begin with and you are given tools that show you the minutia of any slight variation due to weather and or road conditions. Using these same calculations, a 2.5% grade is enough to double your power consumption at highway speeds. Looking at List of mountain passes in Colorado - Wikipedia, every one of the mountain passes listed with a max grade peaks at over 2.5%.

Edit: And to make this relative to the OP, the same energy increase happens in cold weather on gas and electric cars, it's just that the percentage change is a lot higher on the EV since you're so efficient in "normal" operations.

Wow... Bravo, sir. (Assuming your math checks out, which I'm not about to bother checking.)