Seriously?

[gavine]

A lot of people don’t quite understand how driving style can be one of the biggest factors affecting range. It’s not just speed, or fast acceleration. A big part of it is that many assume that regen is 100% (or close to) efficient. It isn’t, and not by a long way.
So every time you dip into the regen area, you’re hurting your overall efficiency. Steady speed driving is always going to be way better than someone who regularly speeds up, then slows down, or people who by necessity dip into regen eg: up and down hills. The good thing about an EV though is that an ICE is much worse, just not so obvious with the information presented. Uphill/downhill is always going to mess with your efficiency, just as stop start will- again though, it’s MUCH worse in an ICE vehicle.
I’ve never met anyone who could legitimately claim to get EPA fuel consumption figures on an ICE. Despite that, it’s kind of funny how many people somehow magically expect an EV to completely break the rules of Physics ..... despite their driving style.

I find that high speed driving eats range faster than anything else. Fast acceleration and regen doesn't seem to affect it as much, provided I hardly use the brakes. I agree that fast acceleration is not efficient, but in my experience, it doesn't put much of a dent in the range. I mean, with a Tesla, you can't floor it very long before you're in going-to-jail speeds so how much energy can you really use on the street? Driving at 85MPH on the highway makes a noticeable dent.

 

[gfunkdave]

70% efficiency is the average I get over the winters in MN.
Your gas car can have it's gas efficiency cut by 40% in a winter pretty easily. It is just that the worse case scenario is typically short so it averages closer to a 20% efficiency cut over the tank.
ALL of my gas cars in the past averaged a 20% loss in the winters.

These are simply matters of physics. All cars loose efficiency due to cold, snow on the ground, rain on the ground, short trips (warm up period).
The only reason you are more aware of it now is you have this cool little tool that gives you instant information.

A bit of empirical data: I have a Honda Accord Hybrid that gets 45 mpg in the summer and 30-32 in the winter, just because of the heat being on....

 

[Rocky_H]

just because of the heat being on....

It's not because of the heat being on. It's because of the cold making combustion burn pretty inefficiently in the engine, so it has to pull more fuel to get the same power. There wouldn't be any difference whether you had the heat on inside the car or not, because it's still putting that heat out your tailpipe and radiator. It doesn't do anything extra to "make" more heat for the cabin; it's just letting you have access to all that waste heat that is there anyway.

 

[VT_EE]

It's not because of the heat being on. It's because of the cold making combustion burn pretty inefficiently in the engine, so it has to pull more fuel to get the same power. There wouldn't be any difference whether you had the heat on inside the car or not, because it's still putting that heat out your tailpipe and radiator. It doesn't do anything extra to "make" more heat for the cabin; it's just letting you have access to all that waste heat that is there anyway.

I have this sneaking suspicion it was a joke.

 

[gfunkdave]

I have this sneaking suspicion it was a joke.

Nah, I just assumed it was because the heat was on. In the summer I usually just have the windows down and the climate control off.

One day I'll be able to justify a Tesla purchase, but a $60k car is alas still out of reach.

 

[adaptabl]

While still using less overall energy than a typical ICE car on the same trip.

It depends on how your electricity is being generated.

 

[gnuarm]

No hills here in Atlanta, but yeah I 'hoon' around a bit, but seriously half the range? That's just ridiculous.

As best I can tell, most of the things people will say affect your range are only small factors. The two things that I find is significant are:

1) I tend to charge up to 90% rather than 100% and like to pull into a charger with 10% left, so there's 20% off the top... same as in an ICE... well, actually my old truck with a manual shift was so predictable I could pull into a gas station with only half a gallon left and know I had half a gallon... or so. But normal people get gas when they are at a quarter tank.

2) Short trips combined with low temps. I do a weekly drive that is 120 miles each way with about 30 miles of local driving while away. That's 270 miles total and I do try to charge overnight from 120 VAC at friends homes. I never made it back without charging in a 289 mile range model X even though the roads I was on were mostly 55 mph and less. Once winter kicked in I couldn't even make it past the destination charger in Leesburg. Now that there is a Super charger about half way on the 120 mile legs if I take the time to get a 90% charge at a Sheetz (nothing to do there!) I can make it back to the Sheetz... usually. But this winter weather is hell on range with the short trips I take in Frederick.

I haven't been able to say that using the heater has a measurable impact on range. I'm told it uses a 5 kW heater which would be significant if it were on very much of the time. Other than when I start out where something is hitting the consumption for maybe four or five miles, I just can't see the impact. I've tried putting the heater on a low temperature and tried setting to a high temperature. I can't see any impact on consumption by the energy graph. The terrain is just so large a factor the graph is mostly pointless. The average consumption number also wanders all over the place even when the car is on auto pilot and not far from flat terrain.

People say to use the estimated remaining charge to tell if you can reach your destination. That seems to work so far. When it is changes, it is usually for the better. But if the car is telling you to stop to charge, you don't get any info on whether you can skip this one and make it to the next charger. Once it was telling me to stop and I missed the exit so I motored on knowing it was close and I could tell where the turn around point was. I made it to the next charger ok without much support from the nav system. It kept telling me to turn around and go back to the charger I missed.

 

[gnuarm]

I think that Tesla should have put out a document to educate people.
Honnestly, I don't regret buying my car, however I would have wished beiing a bit more aware of what to expect.

That's for sure. +1 But if the sales people won't tell you, what do you think would be in the document?

 

[gnuarm]

Nah, I just assumed it was because the heat was on. In the summer I usually just have the windows down and the climate control off.

One day I'll be able to justify a Tesla purchase, but a $60k car is alas still out of reach.

It was a long time ago they found having windows down messes with the aerodynamics to cost more mileage than running the AC does. In a much more modern car were the aerodynamics are so honed, it would be expected to be an even bigger difference.

 

[gnuarm]

It depends on how your electricity is being generated.

When I realized I could power my car at a third the cost of fueling my truck (in reality likely about the same sort of efficiency with a model X, same weight anyway!) I realized there has to be something going on. After some thought and a cold morning spent with no regen, I realized no small part of the improved efficiency of an EV comes from that regen braking. So right there is a significant, pure savings of energy.

Someone in another group had compared the energy path for ICE and EVs. He found the energy losses in electric generation and transmission resulted in about the same energy losses for both ICE and EVs end to end. But he didn't take into account the energy cost of gasoline refining which I don't think is negligible. That may be the other missing piece that combined with the regen make the EV truly more energy efficient no matter what the energy source.

 

[HyperionMark]

It was a long time ago they found having windows down messes with the aerodynamics to cost more mileage than running the AC does. In a much more modern car were the aerodynamics are so honed, it would be expected to be an even bigger difference.

This is true at higher speeds. But windows down at low speeds compared to having the AC on will be more efficient. Probably depends on the vehicle, but the crossover would probably be around 30 or 35 mph for modern cars. (also depends on what temps we are talking)

 

[Rocky_H]

This is true at higher speeds. But windows down at low speeds compared to having the AC on will be more efficient. Probably depends on the vehicle, but the crossover would probably be around 30 or 35 mph for modern cars. (also depends on what temps we are talking)

I've seen the Mythbusters episode on it, and I spotted how they get funny results because of the funny setup of the test. Just like how added efficiencies affect EVs more than gas cars because of the 90% versus 30% baseline efficiency difference, the windows down versus air conditioning test depends on what the baseline efficiency of the gas vehicle is.

Mythbusters was comparing with two huge V-8 gas guzzling SUVs. They have such massive engines and bad efficiency to start with, that the drag of the A/C compressor would be barely noticeable. But with my dad's old Mitsubishi Mirage (also called the Dodge Colt) econo-car, it felt like the car just hit something when you turned the A/C on, and driving the car had no strength, and trying to accelerate on an entrance ramp to the highway was a terrible struggle. The added load of the A/C compressor on small efficient engines is a really big cut to their efficiency.