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Installing two gen 3 wall chargers

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Still working on getting the 2nd charger installed. I have a 200A panel that is at capacity with a 240/50A spa and 240/50A charger (the first one installed 5 years ago). I looked into a 400A upgrade, but we have to move a wall to make room, so that's a no go.

Electrician is going to run a dedicated line back to the panel for the 2nd charger to make it future proof incase we ever do a panel upgrade. An alternative is to put a sub panel in the garage and feed both chargers off of that.

First charger is a 50A circuit with car limited to 40A (upgraded gen 1 to gen 3 already). With 2 chargers sharing 50A, each will be limited to 20A charging current until the smart sharing firmware comes along. This works out fine as we charge starting at 11pm when we have our super cheap EV rates (6.3 cents/kwh) and car is done charging in 4 hours. Even if it takes 8 with 'dumb' sharing, we are still good.
 
Still working on getting the 2nd charger installed. I have a 200A panel that is at capacity with a 240/50A spa and 240/50A charger (the first one installed 5 years ago). I looked into a 400A upgrade, but we have to move a wall to make room, so that's a no go.

Electrician is going to run a dedicated line back to the panel for the 2nd charger to make it future proof incase we ever do a panel upgrade. An alternative is to put a sub panel in the garage and feed both chargers off of that.

First charger is a 50A circuit with car limited to 40A (upgraded gen 1 to gen 3 already). With 2 chargers sharing 50A, each will be limited to 20A charging current until the smart sharing firmware comes along. This works out fine as we charge starting at 11pm when we have our super cheap EV rates (6.3 cents/kwh) and car is done charging in 4 hours. Even if it takes 8 with 'dumb' sharing, we are still good.
Do you still need to 400 amps even if there is a sub panel in the garage?

I debated getting a sub panel for future proofing. I am getting our first Tesla.
My choices were getting a 100 am sub panel along with 1 50 amp charger now leaving another 50 amp for future charger. I decided to get just 1 6/2 gauge wire for a 60 amp charger. It was cheaper to do this vs getting a sub panel in garage. Still wondering if I should get wiring for another charger in future.
 
A 100A or 125A sub panel in the garage will give you the most flexibility. Unless I am wrong an upgrade of this type is considered a permanent improvement to the property for tax purposes. The cost of adding the sub panel should be included in your cost basis if you someday sell the property.
 
They have a power sharing feature that is supposed to be added "soon".

What you can do is to future-proof the setup by installing the proper wires, but limiting the wall connectors to 20-30A to account for a total draw of 40-60A. No good reason to draw 120A on a home with 200A supply.

I'm a big fan of the 30A connection size. Its really hard to justify the extra power when your car is sitting idle and not charging, but I understand that wires are cheap compared with labor so why not.

A lot of people can make it or just barely on a 120v outlet, and 30A is 5-6x more than that.