200 vs 400amp service

[Buddyroe]

Thanks - builder said he talked to the electric company and they don’t charge extra for the service. I find that hard to believe but I’m going to move forward and see what happeneds.

Why would your service cost more because you have 400a service installed? The only difference in 200a and 400a service is the size of the wiring coming to you house. The monthly bill is based on how much electricity you use - that will be the same whether you have 200, 400, or 1000 amp service.

 

[SSonnentag]

Our power company here in Arizona (APS) doesn't charge more for 400A service over 200A. We upgraded ours from 200A to 400A when we had solar panels installed. It cost us roughly $1500 for the upgrade.

 

[Manzacoty]

Why would your service cost more because you have 400a service installed? The only difference in 200a and 400a service is the size of the wiring coming to you house. The monthly bill is based on how much electricity you use - that will be the same whether you have 200, 400, or 1000 amp service.

The size of the wire Coming to the house should be more. But they said it wasn’t so I’m just gonna go with it.

 

[Manzacoty]

For $600, I’d do it.

Just so you know what you’re getting, are you talking a single 400A panel or two 200A? Residential is often two 200A rather than a single 400A panel.

Minor difference, but having loads distributed across two panels makes future solar, sub panels, whole house generator, power wall, etc., more complicated.

It’s going to be 2 200amp panels which I’m already running into complications with a generator I’m wanting to put in. I’m going to have to put all the critical circuits on one of the panels.

 

[SSedan]

Why would your service cost more because you have 400a service installed? The only difference in 200a and 400a service is the size of the wiring coming to you house. The monthly bill is based on how much electricity you use - that will be the same whether you have 200, 400, or 1000 amp service.

I think you will find charging more for an usually large service like that is common, if for no other reason because they figure you can afford it.

 

[Manzacoty]

Gotta got with the crowd here: 400amps for sure.

Reasons:
1- will be several times more expensive to get later, even if only 50amps or so and not even a 2nd 200, so “future-proofing”
2- safer, in that you can divide your circuits by load more easily. For example, more dedicated circuits for appliances, kitchen circuits that include toaster ovens, toasters, microwaves, and other counter appliances.
3- growth (consumption) of electrical devices in the home (Tesla Semi?)
4- troubleshooting ease (fewer circuits with lots of connections)

Only downsides I see are (1) extra $600 for service you may not need, and (2) if you’re considering at any point a whole house standby generator, the transfer switch will be 2x-3x the cost for 400amp with two 200amp panels vs. a smaller switch for one 200amp panel.

We re-wired our 1906 home a few years ago. It had been done a couple of times previously but lots of spaghetti wiring, odd circuits, switches to nowhere, only two circuits supporting the entire kitchen including appliances, and as we found out the grounding had broken/rusted loose. Working with our power company and a great local electrician, we had the power to our home buried in conduit, replaced all the outside load centers (there were 3 of different amperage supplying various parts of the home), upgraded to 400a on two 200a load centers, trenched 100a service to our detached garage and a new load center, replaced the system bonds and grounds, and all was done to today’s code. In addition, the power company had to replace the transformer (their expense) for the upgraded service level. Our motivation was to provide sufficient power for our 2012 Nissan LEAF’s charging station and run the rest of the garage plus a large margin for growth. Add the Model 3 four months ago and it’s all working just fine. At some point I may sell the LEAF and upgrade the J1772 charging station to a Tesla wall unit to get the 48amps to charge the Model 3. But I’m just fine for now.

TL;DR - Go for the 400!

Thanks for the response. I’m already running into issues with the whole home standby generator and the two panels but I think we found a workaround would just putting everything on one of the panels and going with a 200 amp ATS.

 

[dhrivnak]

Hi all - just wanted to get some opinions about the service to a new home we are building. Standard is 200amp service but I can upgrade to 400amp for $600. It’s a no brained right? I have a HPWC and my S85 has dual chargers so I will be pulling down 80 amps (on occasion). Other car is an ICE but hopefully we’ll be all electric soon.

I could deff get away with 200 amps today (our current house has 200) but for the future probably makes sense to go with 400.

Am I missing something or wasting money?

We can’t say knowing other loads. But we have an all electric house and have 3 EVs and have never run into a problem with a 200 amp service. Personally I would spend the money to make your house more efficient.

 

[Black/Black MS]

Hi all - just wanted to get some opinions about the service to a new home we are building. Standard is 200amp service but I can upgrade to 400amp for $600. It’s a no brained right? I have a HPWC and my S85 has dual chargers so I will be pulling down 80 amps (on occasion). Other car is an ICE but hopefully we’ll be all electric soon.

I could deff get away with 200 amps today (our current house has 200) but for the future probably makes sense to go with 400.

Am I missing something or wasting money?

Consider yourself lucky. I am in the process of upgrading my home from 200amp to 400amp, and the total cost will be around $35k.

The one nice fringe benefit is that they will be running a 100amp circuit to my wall charger, which currently has a measly 30 amps powering it.

 

[Feathermerchan]

For those wanting to know why a 400A service may be more expensive than a 200A service:
Pretend you are the utility company. You have investors or members etc that expect you to make money for them. A 400A service has to cost more in materials and possibly labor to install along with a larger transformer. If it generates more revenue, enough to cover the cost then fine. But if it is just being installed because the customer asks and does not offer any reason, then you should charge him more because you are not expecting the revenue to justify the size of the installation..

It all depends on the loads. If the house has no gas and so needs electric heat (even for heat pumps) and say a couple of electric water heaters, a pool with a jacuzzi or hot tub, it is probably going to need all of the 200A service. Then I think installing a 400A service may make sense. Especially if you expect to charge two electric vehicles and drive each one 12,000 miles per year.

In the DFW area, the local utility (Oncor) can install a 200 Amp meter base where the power all runs thru the meter. It is a 200 Amp meter. That is the standard. A 400 Amp service cannot be run thru a 200 Amp meter so they install a 5 Amp meter and current transformers that output 5 Amps when 400 Amps is being used in the house. That costs more. In addition, the utility installs a slightly larger transformer to handle the extra anticipated load.

 

[gilscales]

Yeah those things are not happening on your 200A panel, at least not per code.

We have a steam shower and it has a 100A breaker.

WOW! that must be some shower! biggest unit I found is 12kw takes a 60A breaker and is enough to operate a steam shower/room 7.5' square with an 8' ceiling.

 

[gilscales]

For those wanting to know why a 400A service may be more expensive than a 200A service:
Pretend you are the utility company. You have investors or members etc that expect you to make money for them. A 400A service has to cost more in materials and possibly labor to install along with a larger transformer. If it generates more revenue, enough to cover the cost then fine. But if it is just being installed because the customer asks and does not offer any reason, then you should charge him more because you are not expecting the revenue to justify the size of the installation..

It all depends on the loads. If the house has no gas and so needs electric heat (even for heat pumps) and say a couple of electric water heaters, a pool with a jacuzzi or hot tub, it is probably going to need all of the 200A service. Then I think installing a 400A service may make sense. Especially if you expect to charge two electric vehicles and drive each one 12,000 miles per year.

In the DFW area, the local utility (Oncor) can install a 200 Amp meter base where the power all runs thru the meter. It is a 200 Amp meter. That is the standard. A 400 Amp service cannot be run thru a 200 Amp meter so they install a 5 Amp meter and current transformers that output 5 Amps when 400 Amps is being used in the house. That costs more. In addition, the utility installs a slightly larger transformer to handle the extra anticipated load.

Many years ago I was involved in an addition to a small home that was probably only 1200 sq. ft. the addition was 800 sq. ft. of living space with 800 sq. ft. of garage under it as it was built into the side of a hill the garage had to be on a lower level, the owner insisted he have a 400A service and it was the only one I have ever seen, what struck me was the size of the feed to the panel, looked like garden hose in the 3" pipe, can't remember if SCE had to upgrade the transformers but they did run a new larger drop, there was no extra charge from SCE for this.

 

[Feathermerchan]

Some utilities do this (not charge for an over sized service) but many have learned that if they do not justify the load, then anyone can ask and receive. If the utility commission does not notice, they just pass the costs on to the customers but you can see that it can be a real waste of resources.

Many detached garages in LA were built with no power. LADWP used to charge very little or nothing to add a service to your detached garage. So instead of paying an electrician to run power ($$$) they would just ask LADWP to add a service. Don't know if that is still a practice.

 

[Manzacoty]

Consider yourself lucky. I am in the process of upgrading my home from 200amp to 400amp, and the total cost will be around $35k.

The one nice fringe benefit is that they will be running a 100amp circuit to my wall charger, which currently has a measly 30 amps powering it.

Wowzers. Can I ask why you need to upgrade?

 

[TonyT]

TOU is a nice compromise if you are not going to be there long or cost of a second meter is too expensive to recover. However TOU can be really limiting in the summer of Texas heat!

I missed the part about you being solar, TOU and single 400 would likely be better. It would depend how the credits work, you would need to do the homework and math.

 

[bob_p]

We built a new home in the Houston area 4 years ago, signing a contract while the house was still "in frame" and had the electrical wiring already installed. The house had 2 150A panels to provide power to the house, pool, HVAC, …

We had them add a 3rd 150A panel for EV charging only, and had them run a 100A line on one side of the garage (near the panel) for an HPWC and a 50A line to the other side of the garage for a 14-50 outlet.

The new house also has a number of energy saving features, such as sprayed foam insulation inside the walls. Despite charging two Tesla vehicles, having 50% more floor space, and have 3 150A panels - electric bills at our new house are less than the previous house. So it doesn't appear the utility companies are charging us any more (in Texas) to have more power to the home.

If I was going to change anything, I would have had them run a 100A line to both sides of the garage. Last week, we had a second HPWC installed to replace the 14-50 outlet. They were able to increase the breaker size from 50A to 60A, so we can get 48A of charging through that HPWC. If we'd run a 100A line, we could have placed both HPWCs on the same 100A circuit - and have them share the line (like two vehicles sharing the same supercharger).

We also had the electrician install a surge protector inside our EV breaker panel. While Tesla claims the Tesla charging hardware has built in surge protection - we had some power issues several years ago, which eventually damaged the primary and secondary onboard chargers for our 2012 S P85 - and decided it was worth an extra $200 to get a surge protector added to the EV panel.

 

[SSedan]

FWIW, I have a 40yo leaky 2400sq.ft. bilevel home near Green Bay, 100% electric and resistance baseboard heat till just 2 years ago.

January used to be an extra mortgagpe payment to the power company.

Outside specific high use items I can't see much need for over 200amps in a modern construction home. Obviously if you have a steam shower and want to charge 2 EVs, and the hot tub then yeah the numbers start adding up for potential peak use.

Really doubt the actual physical need would ever be there.

 

[Tam]

Wowzers. Can I ask why you need to upgrade?

I guess if you don't want to use natural gas and you only use electric for water heater, swimming pool heater, steam shower, stove/oven, fireplace, 100A circuit for each Tesla... in addition to other usual HVAC...

 

[HX_Guy]

WOW! that must be some shower! biggest unit I found is 12kw takes a 60A breaker and is enough to operate a steam shower/room 7.5' square with an 8' ceiling.

Its possible our unit was just super oversized? Your shower overall is bigger than ours - ours is 5' x 7' with an 11' ceiling.

 

[ivan801]

I finished my basement (added second laundry room and small kitchen) and suddenly my 200 A service is maxed out. When I added second EV (model 3), I discovered that my charging options are very limited (I already had 50 A in the garage). I looked into upgrading my service, but between what the city wanted to charge, and what my electrician was saying, it quickly passed $5k mark.

 

[Black/Black MS]

Wowzers. Can I ask why you need to upgrade?

I was maxed out and it was just a patchwork of add-ons (100 year old house). My pool house was sharing a circuit with my stove, apparently. It cost so much because they had to trench out and dig up part of the street to install a new power line to my panel.

I installed solar and my power generation was going to be limited by the old panel. On the plus side, solar installs come with a big federal tax credit so at least I got a break on the upgrade.