Range loss in cold weather

[ajdelange]

The most critical screen display, namely "Distance Remaining," is based on exactly what?

Nobody knows exactly and that is perhaps why so many choose the % SoC display rather than the miles or km one. If you do this the little battery symbol display becomes just like the familiar gas gauge we are all used to. Just as you had some idea as to how far you could go in your ICE car with a quarter of a tank of gas remaining (though you probably didn't pay that much attention to it) you will develop an idea as to how far you can go in your BEV on a quarter of a charge and how that varies with road conditions, terrain and weather. You will become sensitized to these things.

But to try to answer your question: the vehicle is constantly estimating the state of charge (SoC) of the battery. Exactly how this is done no one except Tesla really knows but it is probably a combination of coulomb counting (almost every coulomb that goes in comes out) and checking battery open circuit voltage. In % mode it simply displays SoC but in range mode it tries to turn that into miles by calculating the charge and dividing by the miles per kWh. For the driver sub display the consumption is evidently the EPA rated consumption but if you go to the energy display in consumption mode uses the consumption calculated over the last fraction of a mile, a 5 mile, 15 mile or 30 mile window per the drivers choice and tells you want that consumption estimate was. Thus you may have two ranges displayed that are not the same, one next to the battery indicator and a different one on the main console energy display. The energy display in trip mode shows the estimated SoC at destination but you must, obviously, have a destination punched in for this to work. In this mode the destination SoC estimate depends on the average consumption over the selected window and the terrain ahead of you on the selected route. This is the most accurate estimate you will get but depends on future driving conditions being the same as those that you have encountered up to the current point in time. This is an extremely useful display as it shows you what the trip planner originally figured, how you battery use history compares to that and gives you an estimate as to what you will have when you get there. In the X you get about 3 miles per percent on average so if you have an estimated SoC at arrival of 10% you figure you will have about 30 miles margin - perhaps 20 if things don't go well and perhaps 40 if you pick up a tail wind, This makes for total victory over range anxiety one you learn how to read the displays.

Battery voltage?

Yes, I think so as noted above.

Ambient temp?

Yes, I expect so as low ambient temperature effects drag though not dramatically and drag is not usually the biggest consumer of energy, But note that if drag does increase consumption that will be caught in the average Wh/mi calculation and will be reflected in the energy display screens but not on the battery indicator reading.

Distance driven? Load aboard? Recent driving pattern (e.g., hilly terrain, trailer towing, max acceleration)?

These too will be reflected in the energy screen display.

And does it show more readout-sensitivity when within, say, the last 20 miles?

Clearly if you are predicting 20 miles the variance in the estimate is going to be lower than if you are predicting 200 miles out. So yes, the closer you get to destination the more accurate the prediction is. The display shows two lines - one for the initial prediction and one for the actual drive history. The terminal ends of those two curves are often several SoC percent apart.

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[alan auerbach]

Thanks, AJ; appreciate all the effort in your answer!

AJA

 

[SpaceDoc]

Thanks for some of the feedback EV enthusiasts, this is the reason I suggested the topic was to get some conversation and analysis on the topic. It seems to me that there is a fair amount of concern for people who are not familiar with the mode of traveling by electricity. What I was hoping to ascertain if there was a topic or something new occurring. This subject may well not be a concern for the majority of Cybertruck buyers who are affluent enough to purchase this vehicle but if the reason to change is for climatic reasons these vehicles have to be cheaper and with longer range to convince the world’s population to gravitate to electricity. I have heard some frightening statistics on incomes in the US over the previous year , that 44% of Americans make less than 20,000 dollars a year. So the market that Tesla is filling right now is the luxury segment. There a lot of folks out there that can’t even consider this purchase.Hopefully this will change in the very near future or we are just wandering down another rabbit hole.

How many less than affluent Americans buy a decked out Ford F-150?? I live in Texas and they are all over the place. So I imagine a single or double motor Cybertruck will not be a big stretch, especially as most Americans like to incur debt, for better or worse.

 

[SpaceDoc]

I know what your perspective is. You are an alarmist and subscribe to alarmist dogma in the same way you accept the absurd statistic that 44% of the US population is below the poverty line.

That is the stuff of science fiction. There is no way man will ever colonize Mars.

I don't think Musk really cares. He's enough of an engineer/scientist to be very skeptical of the global warming screed and what he really wants to do is neat engineering stuff. Converting the transportation industry to electric and automating it, moving traffic underground, interfacing the brain to machines, providing more renewable energy and smoothing demand, going to Mars... These all qualify.

There is, in fact, most probably nothing to worry about. Climate change has been going on since there was a climate and something or other has survived the most dramatic extremes.

Rapid deployment of EV's isn't necessary but it is definitely beneficial in so many ways that it will happen. I am not a denier. It could all turn out the way the alarmists predict. I am a skeptic. I am a scientist and so, by definition, must be a skeptic. Any "scientist" who tells you he isn't skeptical isn't a scientist.


That's correct. The buyer doesn't care about climate change (with, the exception, of course, of the alarmists).

What's strange about that.? IMO there is nothing to worry about. Unlike you, I accept that I might be wrong. What the future will bring is unknowable. I am smart enough to know that much. I drive electric cars, I fuel them with sunlight to the extent possible, I heat my house with a heatpump with a COP of 3-4 and it runs, to the extent possible, on solar (and I'm increasing my solar). None of these is going to have the slightest effect on what the climate looks like in 50 years and I didn't implement any of them out of concern for the planet. I did them because they represent the best (if not the cheapest) technology.

I do.

As to the politicians - those on the left I regard somewhat lower than child pornographers. Those on the right I hold in slightly higher esteem but I'm not sure they rank above child pornographers either.


Probably not. I am with Aristotle ("The more I know the more I know I don't know") where as you seem to be more of the Dunning-Kruger school.

Well I was able to validate the ones I gave because they came from a reliable source.

No, I never did. But interestingly enough what put me off the global warming thing was the Mann curve. I was working at the time with PCA (Principal Components Analysis - that's a statistical technique) of spectra and becuase of that it was obvious what he had done. When MacIntyre and McKitrick challenged him on it he refused to release his data. Michael Mann is a "liar who figures". Even though the hockey stick curve was debunked the IPCC continued to publish it for years. From this I concluded that Climate Science isn't science at all it is a mix of poilitics and religion and I abhor both. That means that I will not participate any further in discussions of climate change. I am sure the admins and readers are relieved to hear that.


Yes. I gave the number in No. 22.

Ah, didn't realize you have Tesla (not listed in your bio squibb). But yes, it is a problem and they really need to address it. Now that they own the field they can get by with it as is but when the competition comes on line it has to potential to hurt them. In Norway's February sales eTron clobbered Tesla, One of the reasons for this offered by some analysts is Tesla's horrid reputation with regard to service. That may or may not, in fact, be the reason but it is definitely something for Tesla to think about and I am sure that they are.

If by here you mean the people on this forum I am sure most of them think that it is nice that they don't emit CO2 but I expect that this in not the main motivator. Technology/performance probably is with style perhaps second.

Let's look at the video for a second. Right now, it says, transportation uses 28% of the total energy consumed. Penetration of electric in the transportation sector is perhaps 1% so that means that we are saving 0.3% fossil fuel consumption. When 10% penetration is reached that will mean 3% (ignoring the fact that the electricity column will have to increase). BEV's are a drop in the bucket. I wouldn't count on BEVs to save the bacon. Now when all transportation (including airplanes) is electric and all the electric is from renewable sources we have saved 57%. That's significant. That will be a while.

It's pretty clear that you are a denier because you use denier catch phrases and talking points that have been refuted time and again. It's evident that the accelerating climate change is caused by humans and is causing damage to the current climate that humans have evolved with and come to rely on. The evidence has been built by the hundreds of thousands of scientists working in every field from atmospheric science, to geology, to forestry, to oceanography, medicine, public health and so on. Not to mention the mountain of readily observable data that mounts daily of ongoing rapid change all over the world that is well beyond the scope of natural variability. And every major scientific agency and organization around the world that acknowledge these facts and recommend urgent action.

So I guess you suffer from your dogmatic view and your confirmation biases, which are correlated to your age (older and conservative persons being less able to accept the facts of climate change because it conflicts with their world view). Also, the 30 year misinformation campaign by oil companies probably helped form you view, despite how objective you might otherwise think you are.

With regards to Musk, we can only take him at his word. He has stated over and over again that addressing climate change is one of his motivating factors. And colonizing Mars is also one of his motivating factors, which can't be done... until it is.

One thing your responses demonstrate is that EVs have broad appeal, even to those persons who deny climate change, because EVs are practical and a better option than ICE. This is the heart of convincing deniers to take action against climate change, to show them that the alternatives are far better (e.g. EVs, inexpensive renewable energy, conservation, etc., etc.).

 

[ajdelange]

I am not a denier. It could all turn out the way the alarmists predict. I am a skeptic. I am a scientist and so, by definition, must be a skeptic. Any "scientist" who tells you he isn't skeptical isn't a scientist.

It's pretty clear that you are a denier because you use denier catch phrases