Cybertruck price increase?

Crissa

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At 120 V 12 Amps the circuitry is very lightly loaded and...
...That's not how chargers work. That's how power supplies for computers work. They are similar, but not the same.

The charger is in modules, each module is set for a certain pwer draw. To access a different power level, it turns on or off charging modules to reach the value.

It is not like a computer or bench power supply because the voltage needs to be matched to the battery pack. A battery is not just a standard load which lowers the voltage on the battery supply and the rectifier needs to compensate. it's not just a load, but a delicate voltage level slightly higher than the battery's which much be maintained. Like having two reservoirs with a siphon, they need to be balanced lest they overflow (and make the battery go boom).

No, the chargers only run at different efficiencies based upon the voltage in the battery pack. Not how many charging modules (total charging rate) that it is running at.

-Crissa
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HaulingAss

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...That's not how chargers work. That's how power supplies for computers work. They are similar, but not the same.

The charger is in modules, each module is set for a certain pwer draw. To access a different power level, it turns on or off charging modules to reach the value.

It is not like a computer or bench power supply because the voltage needs to be matched to the battery pack. A battery is not just a standard load which lowers the voltage on the battery supply and the rectifier needs to compensate. it's not just a load, but a delicate voltage level slightly higher than the battery's which much be maintained. Like having two reservoirs with a siphon, they need to be balanced lest they overflow (and make the battery go boom).

No, the chargers only run at different efficiencies based upon the voltage in the battery pack. Not how many charging modules (total charging rate) that it is running at.

-Crissa
I'm not claiming to know how the charger is designed, just that charging is less efficient at 120V. And I'm not saying the charger itself is responsible for most of that difference, just a portion of it. And the difference is not tiny, it's enough to easily show up in the actual charge speed numbers Tesla publishes. Look at this and tell me how you would explain the lower number of miles added to the battery per Amp hour of electricity:

It makes perfect sense to cite miles added per hour as long as the amount of current is specified. That completes the comparison and is why I said, "you do the math".

Here's an example:

Tesla says the Model 3 adds about 3 miles of range with 120V @ 12 Amps. 12 Amps current @ 120V = 6 amps of current at 240 V.

Tesla says the Model 3 adds about 44 miles of range at 240V @ 48 Amps. 48 amps @ 240V is 8 times the current of 12 Amps @ 120V.

If the efficiency was the same, you should only get 24 miles of range per hour with 8 times the current. Even if we consider rounding errors (maybe the model 3 gets closer to 4 miles of range per hour at 120V) that would still only be 8 x 4 = 32 miles of range per hour. Yet we get 44 miles of range with 240V @ 48 amps.

I admit this is rough math using miles added per hour but it illustrates perfectly how dramatically the efficiency drops due very low charge rates. It's called "fixed charging overhead". Some parts of the charger and the car have the same consumption regardless of charge rate. The faster charging can be completed, the sooner the car can go to sleep. A car that is charging whenever it is not being driven is not efficient.

This should not be controversial at all. I would hope that all EV owners understand how to get the best efficiency out of their EV's because the difference is not small.
 

Crissa

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It's only a couple percent less efficient at 120 than 240 because higher voltage is just better. It doesn't matter the wattage.

That's why I charge my bike on 240. It produces less heat. Less heat, more efficiency. My bike doesn't actually charge faster at 240.

-Crissa
 

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I've shared my experience accurately as those of a cold climate Model 3 owner. Many live in even colder climates than I do and have had even a more difficult time of it. A Cybertruck owner will have a more difficult time of it due to it's higher energy consumption.

My comments are accurate as shared and I don't appreciate the implication that I'm exaggerating. If you live in a milder climate and/or park the car in a protected space, the results will be better. However, 120V will never be as efficient as 240V charging for the reasons previously detailed and that's why I recommend 30 Amps @ 240V as the minimum home charging solution even in a warmer climate. Some people will not care about efficiency. So be it. It doesn't make anything I've said an exaggeration.
My Model Y is still plugged into 110v outside after nearly A year and my wife is still going to drive it in to her office and home tomorrow.

It’s not an “emergency” here. We get along just fine.

If you want to take offense at that… well that’s on you.
 

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It's only a couple percent less efficient at 120 than 240 because higher voltage is just better. It doesn't matter the wattage.

That's why I charge my bike on 240. It produces less heat. Less heat, more efficiency. My bike doesn't actually charge faster at 240.

-Crissa
Why don't you address the more miles of charge added per Amp hour at 48 amps at 240V and 12 Amps at 120V. The difference is not a couple of percent, more like 27% more efficient to charge at 48 amps. The primary reason for this is the overhead of the charger, the cars computer and the BMS. As long as the car is charging, none of these things can go to sleep. That consumes a significant portion of the 12 amps when only charging on a 120V 15 Amp circuit. When charging at 48 amps a much higher percentage of the power is going into the battery. That's why it's so much more efficient.
 


HaulingAss

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My Model Y is still plugged into 110v outside after nearly A year and my wife is still going to drive it in to her office and home tomorrow.

It’s not an “emergency” here. We get along just fine.

If you want to take offense at that… well that’s on you.
I didn't take offense at that, not at all. But I didn't appreciate you saying I'm exaggerating. The difference is very real. I'm not telling you what to do, I'm just stating a fact that it's far from ideal from an efficiency standpoint and it was very inconvenient for my climate and usage.
 

Crissa

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Why don't you address the more miles of charge added per Amp hour at 48 amps at 240V and 12 Amps at 120V. The difference is not a couple of percent, more like 27% more efficient to charge at 48 amps. The primary reason for this is the overhead of the charger, the cars computer and the BMS. As long as the car is charging, none of these things can go to sleep. That consumes a significant portion of the 12 amps when only charging on a 120V 15 Amp circuit. When charging at 48 amps a much higher percentage of the power is going into the battery. That's why it's so much more efficient.
That's not efficiency. That's overhead. It's basically a flat amount for the controller. It's unrelated to the 120 vs 240 issue.

-Crissa
 

MiguelAznar

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That's not efficiency. That's overhead. It's basically a flat amount for the controller. It's unrelated to the 120 vs 240 issue.
Is this a semantic argument? I think that fixed overhead spread over less charging causes lower efficiency. This interpretation of efficiency applies beyond batteries, for instance to corporations or charities with fixed overhead supporting more or less productive activity.
 

Crissa

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Normally, but the car would take it of the battery, otherwise. What you're seeing as inefficiency is just the vampire drain.

-Crissa
 

HaulingAss

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Normally, but the car would take it of the battery, otherwise. What you're seeing as inefficiency is just the vampire drain.

-Crissa
Not entirely, there is the overhead of the charger/BMS too. If you get done charging 12 times faster your car goes to sleep. People who charge at 120V tend to almost always be charging. The car rarely sleeps. So, yeah, 120V charging causes more vampire drain.

Why split hairs, what matters in the end is how much electricity your car draws to provide your transportation. The fact is, charging at 120V is considerably less efficient compared to charging at 48 Amps @240V.

Tesla's published charge rates at different power levels prove this. Normal vampire drain when not charging doesn't amount to anything compared to the differences we see here.
 


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...That's not how chargers work. That's how power supplies for computers work. They are similar, but not the same.

The charger is in modules, each module is set for a certain power draw. To access a different power level, it turns on or off charging modules to reach the value.

It is not like a computer or bench power supply because the voltage needs to be matched to the battery pack. A battery is not just a standard load which lowers the voltage on the battery supply and the rectifier needs to compensate. it's not just a load, but a delicate voltage level slightly higher than the battery's which much be maintained. Like having two reservoirs with a siphon, they need to be balanced lest they overflow (and make the battery go boom).

No, the chargers only run at different efficiencies based upon the voltage in the battery pack. Not how many charging modules (total charging rate) that it is running at.

-Crissa
You make my head go boom. ?
I've been desperately trying to ignore it but alas, I just can't stand fiction...o_O

You obviously have not heard of or know how CC/CV charging of battery cells work. :cry:
You also don't understand parasitic overheads or circuit efficiency or ohms law. :censored:
What exactly does a "rectifier have to compensate" for ? (the flux capacitor or the virtual reality generator maybe?) :unsure:
I don't think you know what what a rectifier actually is or what it does and it's too late for google to help you. (n)
"Delicate voltage level" to charge? ?
What on earth is a "charging module" and how do they switch? Do you mean the BMS?

The magic that goes on in a battery charger must be astonishing. ???

But maybe it's my fault, because my brain needs a vacuum siphon to understand this faux engineering? :rolleyes:

(and none of this has anything to do with CT price increases either)
 
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Crissa

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The battery heats up the same amount - actually more - for charging at the higher rate. Which means the cooling system has to work a teensy bit longer.

The difference is really very little. And being able to pre-warm from the wall for trips is probably more important than worrying about charge efficiency.

-Crissa
 

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So the M3 was supposed to be $35,000 and now is almost $50,000 and with tax even more. Tesla needs to pay for the factory as fast as possible so they can build 2 more and they know that will lead to being dominant in the world. (and or just add on to existing factories) Tesla also needs a $30,000 hatchback to compete around the globe on price. Ford, GM, Toyota are not standing still and are building several battery plants and upgrading existing assembly plants. I hope they all succeed and we have a glut of EVs to pick from.
I also doubt any significant tax rebate will make it thru the BBB bill. The lawmakers know that the mfgrs will just mark up their EVs and the consumer will still not be able to afford a new car. I think it should be capped at $40,000 for a car or small suv and $50,000 for a truck. Rich people that want more can just pay up.
 
 




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