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I know next to nothing about electricity, panels, circuits, and etc. I have taken pics of the panels I have in my house. The main panel is too far away from the driveway (where I want to install a wall charger or an outlet that I can use with a nema 14-50 adaptor.) the sun panel (I think that’s what it’s called) is near my kitchen which will be less than 10 ft from my driveway where I want to install the charger (it will be on the outside of my house since I have no garage). Here are pics of the main panel and sub panel. What costs can I expect to upgrade the sub panel? Do I need to upgrade the main panel as well? First pic is sub panel near kitchen. Other 3 are main
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I know next to nothing about electricity, panels, circuits, and etc. I have taken pics of the panels I have in my house. The main panel is too far away from the driveway (where I want to install a wall charger or an outlet that I can use with a nema 14-50 adaptor.) the sun panel (I think that’s what it’s called) is near my kitchen which will be less than 10 ft from my driveway where I want to install the charger (it will be on the outside of my house since I have no garage). Here are pics of the main panel and sub panel. What costs can I expect to upgrade the sub panel? Do I need to upgrade the main panel as well? First pic is sub panel near kitchen. Other 3 are main View attachment 833200
Let’s see. The main disconnect on the main panel is 100 amps. So it’s a 100 amp main service. There is a 50 amp breaker in this main panel also which likely feeds the remote 100 amp rated sub panel. If you temporarily turn off that 50 amp breaker does it shut off everything on the sub panel?
 
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ucmndd

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Mar 10, 2016
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Let’s see. The main disconnect on the main panel is 100 amps. So it’s a 100 amp main service. There is a 50 amp breaker in this main panel also which likely feeds the remote 100 amp rated sub panel.
Agree with this interpretation of the photos.

The immediate problem I see is that your sub panel is full. You could free up one slot by combining two of those single 20 amp breakers into a tandem, but you need TWO free slots for a 240v circuit. Not sure if they make quad tandem breakers for that Square D panel or not.

Assuming you can address the physical problem, you still have a very full sub panel and only 50 amps to work with. I think the MAX you could get away with devoting to EV charging would be 20 amps, and even that is pushing it depending on what other loads that panel feeds. One of those circuits is labeled “heater” which would be another high current load, so I’m further skeptical a load calculation of that panel would yield much/any room to work with.
 
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I don't know enough about electricals to comment on the layout of the sub panel, breaker types, etc.

Regarding load calculation though, if you're up to your max load already, one of these may be an option for you. I know in Canada you can install an EV charger without it affecting your load calculation with one of these. My service is 100amps, and I had no overhead left, so one of these saved me a service upgrade to 150/200A. Though whether it will work with your sub panel, I can't say....

 
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In fact, call 2 or 3 of them.
Yeah, call 8 or 9 of them. The numbers can vary wildly. I received $3-4k quotes for just a service upgrade.

Ultimately I ended up with a 200 amp service upgrade, two new sub panels (to 2 garages), burying of the overhead (copper cloth) lines to the garages, another buried circuit to a yard playground, and Tesla HPWC installation for $4k. Note: I consider that to be an excellent deal.
 
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It looks like you shouldn’t be making coffee while drying your hair. Using the DCC you could get 60 amp service from the main panel sometimes, and 50 amp service from the subpanel sometimes. It’s easy to install, but I’ve never met an inspector who’s heard of it before, so tell them first. If they allow it and you want to use it from the sub panel you’ll have to upgrade the panel first for more space (a few hundred $).
 
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Quick piece of advice...a 50amp breaker (pretty standard for EV chargers these days) is overkill for the majority of EV owners. You probably won't get any smart electrician to install a 50amp breaker on your 100 amp service so here's my advice to save tons of money on a $4k+ panel upgrade...

Consider a 20amp/240V breaker...that provides 16amps of continuous draw @ 3.8kw. 3.8kw will provide 46kwh (140-240 miles depending on car model) of charge to your car, in 12 hours, which seems like a conservative amount of time to be parked at the house each day. You lose some charging efficiency since the computer has to be running the whole time it's charging. Wasting $0.20 a day running the computer/charging equipment, during extending charging sessions.

I know this doesn't fix your breaker space issue. That's up to the electrician to re-arrange some of the stuff in that sub-panel, which might not even be possible based on load calculations.
 
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I have a 50A breaker on 100A service. Fully installed to code by professional electrician who specializes in EV / Tesla charger installs. I also have AC and some electric heat, in addition to the standard stove, dryer, etc.

My load calc would not have allowed me to even install a 20A normally, but with the use of the DCC12 I posted above I was able to go all the way to 50A with no increase in load calc, therefore no service or panel upgrade required.
 
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I have a 50A breaker on 100A service. Fully installed to code by professional electrician who specializes in EV / Tesla charger installs. I also have AC and some electric heat, in addition to the standard stove, dryer, etc.

My load calc would not have allowed me to even install a 20A normally, but with the use of the DCC12 I posted above I was able to go all the way to 50A with no increase in load calc, therefore no service or panel upgrade required.
As long as that device is approved by your utilities, it's much better than upgrading panel. However, OP's main is too far from the car. Sub is much closer.
 
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