Need help with home charger install

[Ecupip]

Finally had a company visit to see about installing the home Rivian charger. They say I need to go to a 400A service because my current potential load is 161A on my 200A service. They sent me a bill for $8,779.95 to upgrade to 400A. I'm very curious if there are other ways to install the charger without going to this much expense.

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[SilverII]

Do you have a pool, hot tub, all electric appliances or a massive house? If so, you may have to upgrade service

 

[Ecupip]

Do you have a pool, hot tub, all electric appliances or a massive house? If so, you may have to upgrade service

It’s not very large, it’s 3300sqft. We are all electric though. 2 ac units with electric heat backup, 1 well pump, 1 dryer, 1 heat pump water heater, 1 induction cooktop, 1 electric oven. No pool or hot tub.

 

[SilverII]

You probably can do a 50A breaker and run the wall charger at 40A. However, the charger can go full 48A on 60A breaker so you will not be at full speed

 

[SANZC02]

Finally had a company visit to see about installing the home Rivian charger. They say I need to go to a 400A service because my current potential load is 161A on my 200A service. They sent me a bill for $8,779.95 to upgrade to 400A. I'm very curious if there are other ways to install the charger without going to this much expense.

I would get a second opinion, sounds like a normal setup and a 400 amp service is not very common for residential.

 

[Dark-Fx]

I've got a 110A sub panel off my 150A service. If we're just doing overnight charging I have no concerns about maxing out the sub panel, but we're typically only charging one EV at a time anyway. We have city water and gas stove/water though, so those big power consumers aren't a consideration for us.

 

[Ecupip]

Thanks everyone! I scheduled a second opinion with Emerit since they are supposed to be pretty good with ev charging. Will update the thread after they visit.

 

[Electrified Outdoors]

Good decision. If the potential load includes a 60 amp circuit for the charger the simple solution is to do a 50 amp circuit instead. That will drop it below 160 (80% of the 200 amp service) and not require a heavy up. The Rivian charger can be configure to charge at a slightly slower speed to suit the 50 amp breaker.

 

[windblowlc]

Thanks everyone! I scheduled a second opinion with Emerit since they are supposed to be pretty good with ev charging. Will update the thread after they visit.

Home charging will be mostly at night when you won't be at full load. I don't imagine you'd need a 400A service.

 

[Ecupip]

Good decision. If the potential load includes a 60 amp circuit for the charger the simple solution is to do a 50 amp circuit instead. That will drop it below 160 (80% of the 200 amp service) and not require a heavy up. The Rivian charger can be configure to charge at a slightly slower speed to suit the 50 amp breaker.

Unfortunately, the current load is 161A not including the future load of the car charger

 

[Monkey]

Finally had a company visit to see about installing the home Rivian charger. They say I need to go to a 400A service because my current potential load is 161A on my 200A service. They sent me a bill for $8,779.95 to upgrade to 400A. I'm very curious if there are other ways to install the charger without going to this much expense.

As others have said, get a second opinion. I don't doubt you have that amount of load on your panel, but at the same time it seems a bit high. I have a 4200sq. ft. home with 200A service. Two AC units, double electric ovens, steam shower/sauna, all the usual lights, TVs, etc.. And I'm already running a car charger at 40A. I wanted to add a second while upgradinging the current 40A unit to 48A... I had a few electricians give me quotes to upgrade service to 320/400A to make this work and they ranged from just a fuzz under $7K to almost $9K, with the best price coming from an electrician that does a lot of work for me on some of my commercial properties. That said, we're just going to stick with what we've got. The expense isn't worth it to add a second charger...

 

[mikehmb]

Good decision. If the potential load includes a 60 amp circuit for the charger the simple solution is to do a 50 amp circuit instead. That will drop it below 160 (80% of the 200 amp service) and not require a heavy up. The Rivian charger can be configure to charge at a slightly slower speed to suit the 50 amp breaker.

+1 to this idea.

For different reasons, I just de-rated my Rivian charger to 40A so I could keep the same 50A breaker on the circuit.

 

[atebit]

So when I built my house in 2015, I actually speced 400A service, because at the time, 240V@80A was a thing, and I fully expected at the time to have AT LEAST 2 EVS (and will once Porsche releases the EV Boxster). The electrician only charged me an addi

Anyway fast-forward 8 years and 80A charging has gone the way of MySpace. But even with that 80A EVSE, and otherwise all-electric w/geothermal heat, 400A was undersubscribed even with the AC, electric oven, and the EVSE going.

IMHO, I think your electrician is just doing their due diligence by recommending a service upgrade. I don’t know if the Rivian EVSE has this capability, but you can hard-code the Tesla EVSE via a DIP switch to limit it to a number of different max amp settings. If you turn the breaker off & are comfortable removing the cowl, you can fiddle with this setting yourself (up to the “continuous” de-ration of the servicing circuit breaker of course). So you could “start low” and work your way up to what your other daily loads dictate*

*I am not a licensed electrician and these are just my musings. Discuss any options with a licensed professional in your town/city and follow their recommendations!

 

[HaveBlue]

Fill this out for your house and you can get a good idea if he did the math right. My guess is yes however if you manage usage and charge overnight, you should have no trouble. People charge Tesla's off 50A main panels.

https://ask-the-electrician.com/residential-electrical-load-calculation.html

 

[Electrified Outdoors]

Unfortunately, the current load is 161A not including the future load of the car charger

Ok, get a 2nd opinion is good. Make sure it's inspected whatever you have done.

You may wind up having to upgrade service. I have 200 amp and am on well and septic but I have HWH, main furnace, and stove running off propane. In newer homes local governments are pushing for all electric appliances in many areas. If everything in a home is electric and you have a larger newer home that also has well, septic, and fire suppression then 200 amp is barely enough. If you live in a town that has public water and sewer that can make the difference.

We also have a heat pump for the upper level with electric backup. In a larger home (usually > 3000 sf) it's usually more than one HVAC.

Also, I plan to replace my HWH and Dryer with the new heat pump variety when the time comes. Would also like to go Geo Thermal when that time comes. Assuming we don't move again.

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