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Electrician Saying 200 amps is maximum for residential in Los Angeles. Is that true?

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Be sure to read the tankless hot water heater thread. Lots of good information there about how bad they are for various reasons.

My 1,200 square foot house is home to two Model 3s, a Fiat 500e and a Cadillac ELR plug-in hybrid with three drivers. Our service is 125 amps and we get by just fine. We have two wall connectors sharing a 50 amp circuit and two other 30 amp circuits for car charging. Total charging load is just under 80 amps (40+24+15) since the Cadillac has a slow 3.3 kW charger. The main bottleneck is the wimpy 50 kVA transformer that feeds my house and six of my neighbors. Regardless, we have never had a problem getting a full charge on all of the cars overnight, even in the summer when neighborhood air conditioning loads are high and we have to throttle back the charging speeds to avoid unacceptable voltage drop.

What you’re proposing can be done with 200 amps. The cars don’t need to charge as fast as possible simultaneously and it’s unlikely that you’ll be fully replenishing the Tesla batteries every night.

My recommendation: install two wall connectors sharing a 60 amp circuit, then install two J1772 stations sharing a 50 amp circuit. The Teslas will charge at the full speed of 48 amps when charging individually or at 24 amps each when charging together. The other EVs will charge at 20 amps each when charging together, which is plenty of time to fully charge them in the overnight hours. Finally, look into a hybrid heat pump hot water heater. It will likely save you enough money on electricity to cover the power used by one of the vehicles.
 
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I use 2 HPWC's on one 100A circuit through a 200A main panel. There can be up to four HPWC's per circuit. With two, I can get 72A or 48A for our X or 3 when they are charging alone. If they are both charging they both get 40A. We stagger their scheduled charging start times, but that's not really needed.

The HPWC's are flexible enough to use just about whatever size circuit you can support (do a load calculation!). So you might even be able to fit something like a new 30A circuit using your existing 100A panel, shared with three HPWC's. Even with 3 or 4 EV's to charge, how many times will you need to charge all of the simultaneously from 0% to 100%? You may be able to use relatively slow charging overnight and still top off everyone's car. You can charge faster if you're only charging one car. I'm pretty sure there are non-Tesla circuit-sharing charge connectors, though they probably won't share with Tesla HPWC's. You should be able to modify an HPWC with a non-Tesla cable and handle from one of the EV charging stores. Or install one 14-50 and three HPWC's, though that ups the panel load or reduces the current available for the HPWC's.
 
Great points in this thread already, I'll make one more crazy suggestion.

There are EV chargers (of the J1772 variety) that can loadshare over 4 units. I propose getting 4 such units on an 80A (or even less) shared line, and using the J1772 adapter for the Teslas.

As pointed out, it is very likely that at 240V, even lower currents will be sufficient to charge all vehicles overnight. Without knowing everyone's commute that will be using it, I'd say 240V@10A would very likely be sufficient to cover average needs so you'd only need to share a single 50A circuit.

An aside: In this thread I learned that electric instant water heaters exist, I thought they only existed for natural gas! Even in the case of gas they have a bad reputation if for no other reason than they're less efficient than a gas heated tank. The draw from an electric instant heater is absolutely insane.
 
400 amps for a residential home.... You crazy....
Sounds like you need an automatic switch over switch. I dont know exactly what that means but it has to be possible. Basically plug in all vehicles whenever and once each vehicle gets fully charged it automatically disengages a relay and energizes the next vehicle. Would be a little more involved but possible if you have the right people and controls. You would also need a but of money to make it happen too.... LOL

Tesla should make a control panel....
 
400 amps for a residential home.... You crazy....
Sounds like you need an automatic switch over switch. I dont know exactly what that means but it has to be possible. Basically plug in all vehicles whenever and once each vehicle gets fully charged it automatically disengages a relay and energizes the next vehicle. Would be a little more involved but possible if you have the right people and controls. You would also need a but of money to make it happen too.... LOL

Tesla should make a control panel....

Circuit-sharing charging stations are much easier. The more cars that are plugged in, the slower they go. Same end result as staggering their charge times without having to create a device to manage charging times.
 
That's not even accounting for all other appliances at home such as our 2 refrigerators and server I keep on at all times, let alone our 5 computers usually turned on. We're already tripping the breaker without charging any cars as is with our 100 amp service.

That's a VERY dangerous situation. You've got very old wires heating up past their rating. This screams fire hazard. It also tells me that you already don't have enough headroom to charge a car.

There isn't infinite power at the street that you can draw from. There's a shared transformer that you and your neighbors all pull from. It's sized for the number of houses that you server and the service that was installed when the houses were built.
Going to a 400A service is going to possible mean that the main service line from the transformer to your house is replaced, the shared transformer replaced, and possibly a upstream transformer replaced.

It may be cheaper, even in LA, to buy a new house.
 
The electricians you've spoken to are generally correct, residential service these days basically comes in multiples of 200 amps.

That may be true, but the panel is often the limiting factor. My home in Jackson (1600 sq ft) was built with a 200-amp panel and I upgraded it to 300 amps by replacing the meter. My utility told me they ran 400-amp service to my home but to upgrade to 400 amps would have required a new panel which means a lot of labor. Most homes in Jackson use electric baseboard heat so 300 and 400 amps is not unusual.

My home in Vegas (2400 sq ft) has 400-amp service but has a 320-amp panel. Again, it would require a monumental amount of labor to replace the 320-amp panel with a 400-amp panel.
 
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So, I just bought a house earlier this year. Prior to that, I was charging for all of 2018 exclusively on superchargers. It's a very old house with an old 100 amp service panel located right next to the gas water heater (they almost touch).

I want to upgrade my electric panel to at least 320 amps, but my electrician keeps insisting that 200 amps is the absolute maximum for a 1,200 square foot home like mine. You see, I have a Model 3, my wife has a Fiat 500e (soon to be replaced by another Tesla), my sister has an e-Golf, and my parents are considering a Model Y. That's 4 electric cars in total, or 240 amps if charging at the same time, just for the cars. Right now I'm charging my Tesla at work and superchargers, and my wife and sister take turns charging from a 120V outlet. It's extremely inconvenient.

We've already installed the wiring for 3 NEMA 14-5 outlets (2 inside garage, 1 outside), and an exterior Tesla HPWC. All that's left is to connect them to the electric panel after upgrading it.

We know a family electrician that flat out refuses to do anything more than a 200 amp panel, saying that 300 isn't a thing and 400 would require extra hurdles only for commercial properties. Is that true?

I've gotten (MUCH more expensive) quotes from other electricians. Some of whom agree with him in that it's not possible, and others who say it's okay as long as I get explicit permission from the city. Does anyone have any experience with this?
There are 225A metered main panels available and while it is not a big difference from a 200A panel, it is something extra and would allow a 180A sustained load.
Square D Homeline 225 Amp 30-Space 42-Circuit Outdoor Ring-Type Semi-Flush Mount Solar-Ready Main Breaker Plug-On Neutral CSED-SC3042M225PF - The Home Depot
 
The comments about unavailability of over 200 A service are wrong. It totally depends on the status of your very local grid. Internet comments are useless; contact the utility directly.

My house in RI has 300A service, and my house in ME has 360A. Both houses are over 100 years old.

Regardless of how much you increase the service, get the biggest possible panel. I find you often have to add circuits, and you don't want to run out of space. I have had to add two daughter panels (three total) at one house.
 
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There are EV chargers (of the J1772 variety) that can loadshare over 4 units. I propose getting 4 such units on an 80A (or even less) shared line, and using the J1772 adapter for the Teslas.
That could work, but I'd prefer to go with @BPeter's recommendation of Tesla Wall Connectors instead. The idea would be to use as few adapters as possible and thus minimize fussing around whenever a car needs to be plugged/unplugged. I'd rather be stuck with a single Tesla-->J-1772 adapter than three J-1772-->Tesla adapters!

When we first got our Model S, we used the J-1772 adapter every night. It was very nice to install a Wall Connector and be able to push the little button on the handle to open the car's charge port. Also, the car's charge port was sometimes finicky when the J-1772 adapter was being used, and this became a non-issue with the Wall Connector.

Also, a home in Los Angeles would be a good candidate for an electric heat pump water heater (see that other thread).
 
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My parents neighbor does a totally insane Christmas display every year. She ended up having to upgrade her 200 amp service and the only option that the electrical company allowed was a second 200 amp meter. It ended up costing almost 10 grand.

But as others have mentioned, it’s completely based on your electric company, and upgrading your service is probably a last resort option. There’s several solutions that would allow you to have 4 vehicles plugged in at the same time and share whatever power is available.
 
The comments about unavailability of over 200 A service are wrong. It totally depends on the status of your very local grid. Internet comments are useless; contact the utility directly.

My house in RI has 300A service, and my house in ME has 360A. Both houses are over 100 years old.

Regardless of how much you increase the service, get the biggest possible panel. I find you often have to add circuits, and you don't want to run out of space. I have had to add two daughter panels (three total) at one house.
That being said, I do think LADWP allows it.
 
I am in PG&E territory in Northern California. I have a main panel with a 320A meter socket and space for two separate 200A main breakers. Only one main breaker is populated and feeds the built-in 200A bus. The second main breaker could feed a separate 200A panel. This house was built in 2012 and I had the pleasure of speaking with the PG&E engineer about our project. He suggested several things and in retrospect, I should have done it a different way. One of the other options was to get the 320A service and run separate meters for the house and EV charging. I did not do that because I knew I was going to get solar and I wanted the solar to offset the car charging. It turns out that there is a thing called Net Meter Aggregation. I think this can be used to assign some NEM credits to the EV meter from the house meter. Now that the utilities are devaluing solar by extending the Off-Peak hours through the morning into the early afternoon, it makes more sense to separate the solar and EV charging plans.

Anyway, even though I have the larger service, I can service my needs with a 200A panel, including two 14-50 outlets for car charging. If you need more than 100A of car charging circuits, load balancing with Tesla Wall Connectors or other solutions is the way to go.