How many are getting the solar option

Crissa

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You'd need enough solar to run a 2KW inverter continuously, minimum charge rate is 1.4KW AC.
This is not true. There would be no reason to use an AC inverter - and even if you did, the minimum Tesla step is 700W (5a), not 1.4kW - for the incoming DC power. You would just need MPPT modules to step the voltage to the battery. They will need this for the solar tonneau in the first place.

-Crissa
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lqdchkn

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This is not true. There would be no reason to use an AC inverter - and even if you did, the minimum Tesla step is 700W (5a), not 1.4kW - for the incoming DC power. You would just need MPPT modules to step the voltage to the battery. They will need this for the solar tonneau in the first place.

-Crissa
Tesla's charge on AC, solar is DC so you need convert DC to AC so the car can convert the AC to DC again, it's a waste.

Now if you want to talk about DC charging then you need way higher voltage that what standard panels are capable of. When I looked up the DC spec I believe it 480V was what was needed to DC charge.
 

ajdelange

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I thought I'd covered this in No. 104. Perhaps I wasn't clear:

1)Teslas run on batteries. They must be charged with DC.
2)The Tesla nominal battery pack voltage is 385 V. To get current to flow into a 385V battery you must apply more than 385 V to it.
3)Anything that charges a Tesla battery regulates its voltage to the value (above 385 nominally) to that which causes the desired current to flow. At the moment that means A/C power supplies internal to the vehicle or external in a SC cabinet.
4)If Tesla wishes to facilitate charging from solar panels it will have to build in a third type of charger which would include connectors which allow the attachment of standard solar panel connectors. The electronics will have the regulating converters needed to charge the battery while still satisfying the requirements of MPPT.
5)If they do not do this then you will need to charge an auxiliary battery (such as a Jackery or Yeti unit - both of which have MMPT trackers on their solar inputs) and then charge the vehicle from the auxiliary battery's inverter via the vehicles internal charger which can charge at any rate between 0.6 and 11.5 kW. Obviously 4) will be most efficient.
 

Marvin112

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I’m thinking about it and it depends on the cost compared to the benefit. I’m hoping it will be worth it as it’s pretty awesome.
Im there in concept, we'll see what's actually offered.
Yeah. Reasonable price offer can be a source of encouragement to have it with the consideration of benefits.
 


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I thought I'd covered this in No. 104. Perhaps I wasn't clear:

1)Teslas run on batteries. They must be charged with DC.
2)The Tesla nominal battery pack voltage is 385 V. To get current to flow into a 385V battery you must apply more than 385 V to it.
3)Anything that charges a Tesla battery regulates its voltage to the value (above 385 nominally) to that which causes the desired current to flow. At the moment that means A/C power supplies internal to the vehicle or external in a SC cabinet.
4)If Tesla wishes to facilitate charging from solar panels it will have to build in a third type of charger which would include connectors which allow the attachment of standard solar panel connectors. The electronics will have the regulating converters needed to charge the battery while still satisfying the requirements of MPPT.
5)If they do not do this then you will need to charge an auxiliary battery (such as a Jackery or Yeti unit - both of which have MMPT trackers on their solar inputs) and then charge the vehicle from the auxiliary battery's inverter via the vehicles internal charger which can charge at any rate between 0.6 and 11.5 kW. Obviously 4) will be most efficient.
Merci for your explanation... as we have a lot of cloudy sky (not like the lucky people of the south) and our electric price is the lowest... I will not invest in that for now...
 

lqdchkn

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Yes, but no. Yes, their low-powered charger is AC, because AC is plentiful. But no, they do not 'charge' on AC, that charger is just converting AC to DC because batteries charge on DC.

-Crissa
Topic is about solar charging. Stating anything other that how solar outputs vs Teslas accept power input is irrelevant.
 

Crissa

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lqdchkn

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Clouds don't mean no solar. They just mean reduced. Many cloudy days will still have half or more power from a solar arrays.


Wha?

Wha??

Solar is DC. Batteries are DC.

-Crissa
I dont think you understand what your stating. MPPT controllers cannot boost voltage beyond what your panels can put out. Additionally if you want to change straight DC to DC you still need to supply 400V DC into the car. Go find 400V panels and go find a 400V MPPT controller and price it out. I'll wait.
 

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I dont think you understand what your stating. MPPT controllers cannot boost voltage beyond what your panels can put out. Additionally if you want to change straight DC to DC you still need to supply 400V DC into the car. Go find 400V panels and go find a 400V MPPT controller and price it out. I'll wait.
https://m.alibaba.com/product/62269577228/solar-charge-controller-400v-80A-mppt.html

https://www.enfsolar.com/pv/charge-controller-datasheet/921

Looks like about $200
 
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ajdelange

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I dont think you understand what your stating. MPPT controllers cannot boost voltage beyond what your panels can put out.
I wonder where you got that idea.


Additionally if you want to change straight DC to DC you still need to supply 400V DC into the car. Go find 400V panels and go find a 400V MPPT controller and price it out.
At least you have accepted that the voltage required of a Tesla charger is 385 V or so but you continue to ignore the explanations of what a MMPT DC/DC converter does. I'm guessing that a third repetition would be similarly ignored so instead I will offer up the Enphase IQ7 microinverter as an example of a MPPT converter which produces probably 380V DC from a maximum of 48 V DC input (I have 58 of these on my roof). I say "probably" because the DC is immediately chopped up into 240VAC and injected into the grid using the same principle that I have described before. The injected current is increased until no more can be obtained at which point the unit is producing the maxium amount of power that can be obtained from the panel to which it is connected under the current solar flux.

There now. I didn't keep you waiting too long, did I?
 

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I'm not an electronics wiz like some people here. But I know it's pretty easy to step up or down voltages, of course you will lose something, amps? So if you have a panel that puts out like 50 volts. You could theoretically just boost it to 400.
 

ajdelange

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I'm not an electronics wiz like some people here. But I know it's pretty easy to step up or down voltages, of course you will lose something, amps?
What stays almost constant is the product of current and voltage so that if you have a 100 volt supply capable of delivering 100 amperes thats 100 x 100 = 10,000 VA (volt amperes which for DC is 10,000 Watts. If you step the voltage up to 400 V then the current goes down to 25 A - still 10,000 VA. Some of the power is lost so that if you put 10 kw in you might only get 9.5 kW out IOW 500 W would be lost as heat.

But I know it's pretty easy to step up or down voltages
It has always been very easy to step AC voltage up and down. Just take a piece of iron and wind some wire around it. Now on top of that coil wind another coil with 4 times as many turns. Put 120VAC across the first coil and you will have 480 across the second. This is not the case with DC and is why Westinghouse beat Edison in the "Current Wars".

But today we convert DC to AC and vice versa with amazingly high efficiency and so can convert any DC voltage to any other simply by converting it to AC, running through a transformer (pair of coils on a magnetic core) and then rectifying the stepped voltage back to DC. The onboard charger in the Tesla's work this way but it's not actually necessary to have a transformer (half a transformer will do).


So if you have a panel that puts out like 50 volts. You could theoretically just boost it to 400.
That's what the new Tesla solar charger would do. The only extra requirement is that it boost the voltage to such a level that the current taken from the solar panels optimizes the loading on them.
 
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Crissa

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I dont think you understand what your stating.
I don't think you understand what you're saying. A controller for a 400v battery would have to be designed for that battery. There's no reason you couldn't step the voltage up to right level.

And every one of your responses have been rather perpendicular to the conversation. What does your complaint about MPPT controllers have to do with you asserting that they needed AC charging?

-Crissa
 

ajdelange

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but Tesla's im pretty sure need to to be on pure sine wave too.
This was, and I guess still is a common misconception supported, I expect, in some measure by the admonition in the Tesla manuals to not charge their cars from a "privately owned generator". The reason I am bringing this up again here is that Rivian has just put up a FAQ page and on it they say, in answer to a question about generator charging "As long as it can power your home, you can charge your vehicle." I have always been puzzled by Tesla's position on this and especially by their choice of wording.
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