Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

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MCST
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Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by MCST »

We have 200A service to our 10 year old house. We do not have solar (yet - still considering it if the price is affordable).

We currently have:
1. EV
2. Heat pump w/backup heat strip

We want to add:
1. Induction range
2. heat pump or electric water heater

Our current GE breaker panel is essentially out of space. I had a whole home surge protector added when we got the heat pump, which used up the rest of the space we had.

I had a couple electricians look at adding 220 service so we can get an induction range. Because our range is on an exterior wall between the houses, both recommended running conduit on the exterior of the house and drilling through the wall, rather than trying to figure out how to get the wire through the interior walls which would likely require lots of cutting and damage.

The first electrician said we should just replace our entire panel since there's not enough room. The second said he'd recommend adding a sub panel next to it, which is fine under code and will be a lot cheaper. He said we should maybe consider an entirely new panel only if we're getting solar. Getting an entirely new panel is not cheap.

When I had an inspector out to look at the heat pump they said that our 200A service may not be enough if we want to add an induction range and heat pump water heater, but the cost to upgrade to 325+ would cost 15-20k.

Questions:
1. is there any downside to running conduit on the exterior of the house (it's not very visible) to the kitchen for 220 service?
2. Should 200A service be sufficient for the appliances we have (EV, heat pump, heat pump water heater, induction range)?
3. Should I look at replacing the entire panel, or is a sub panel ok?

I remember when 200A seemed like more than enough power, but this inspector has me concerned. He mentioned that we need to do a load calculation, so I'll see if I can find an electrician who will do that.
hudson
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by hudson »

MCST wrote: Wed Jul 10, 2024 7:13 am We have 200A service to our 10 year old house. We do not have solar (yet - still considering it if the price is affordable).

We currently have:
1. EV
2. Heat pump w/backup heat strip

We want to add:
1. Induction range
2. heat pump or electric water heater

Our current GE breaker panel is essentially out of space. I had a whole home surge protector added when we got the heat pump, which used up the rest of the space we had.

I had a couple electricians look at adding 220 service so we can get an induction range. Because our range is on an exterior wall between the houses, both recommended running conduit on the exterior of the house and drilling through the wall, rather than trying to figure out how to get the wire through the interior walls which would likely require lots of cutting and damage.

The first electrician said we should just replace our entire panel since there's not enough room. The second said he'd recommend adding a sub panel next to it, which is fine under code and will be a lot cheaper. He said we should maybe consider an entirely new panel only if we're getting solar. Getting an entirely new panel is not cheap.

When I had an inspector out to look at the heat pump they said that our 200A service may not be enough if we want to add an induction range and heat pump water heater, but the cost to upgrade to 325+ would cost 15-20k.

Questions:
1. is there any downside to running conduit on the exterior of the house (it's not very visible) to the kitchen for 220 service?
2. Should 200A service be sufficient for the appliances we have (EV, heat pump, heat pump water heater, induction range)?
3. Should I look at replacing the entire panel, or is a sub panel ok?

I remember when 200A seemed like more than enough power, but this inspector has me concerned. He mentioned that we need to do a load calculation, so I'll see if I can find an electrician who will do that.
No recommendations....my experience.
In '75 when I bought the house, I had a 200A breaker box.
When I did remodeling 10 years ago the electrician said that my breaker box was too old and replaced it with a new 200A breaker box.
My 200A breaker box runs 2 heat pumps (one with heat strips) and an induction range.
I know nothing about solar or EVs. On first reading, I missed that you had a Tesla type vehicle. (Label me old-school.)
In my working days, I had access to two electrical engineers and two electricians. They could take one look at a house and make the correct call.
I still have one of those guys on speed dial. Therefore you could probably list the high draw items in your house and get a good load estimation right here. Maybe one of these links would do the job? https://www.google.com/search?q=diy+hom ... e&ie=UTF-8
Last edited by hudson on Wed Jul 10, 2024 9:54 am, edited 3 times in total.
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TomatoTomahto
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by TomatoTomahto »

I can’t answer your question directly, but will say that when we bought our house, I thought 400A service was overkill. We have since gone all electric (heat pumps, EV, induction stove, etc.). I was surprised that when we wanted to get an electric hot tub to replace our propane one, the electrician was concerned about having enough juice.

The trend clearly is to electric. I’d go large.

You will enjoy your induction range.
I get the FI part but not the RE part of FIRE.
Luke Duke
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by Luke Duke »

MCST wrote: Wed Jul 10, 2024 7:13 am The second said he'd recommend adding a sub panel next to it, which is fine under code and will be a lot cheaper. He said we should maybe consider an entirely new panel only if we're getting solar.
This is your answer.
No solar = sub-panel
Solar = new panel
EricGold
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by EricGold »

Are you talking about an additional range, or replacing one you have ? If additional, you can go by NEC 230.55 for additional load

Sized and Used correctly, hot water heat pumps pull about 1/10 the power of a standard electric water heater

---
You are asking two very different questions
1. How to solve a need for more breaker space. If just that, then sub-panel
2. If you need a larger service

The standard answer of electricians for more load is a larger service, but you actually have much cheaper choices. A few off the top of my head ..
1. Most EVSE will let you set the max Amps. Reduce the EVSE load commensurate with the extra range load
2. "Tie" a couple of loads together via smart breakers to ensure they are non-coincident
3. If your current water heater is electric, see above. Load problem solved
4. Do or get a load calc. Article 230 in the NEC has the recipe, although I'm not sure if a casual reading will be clear enough to use.
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Sandtrap
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by Sandtrap »

MCST wrote: Wed Jul 10, 2024 7:13 am We have 200A service to our 10 year old house. We do not have solar (yet - still considering it if the price is affordable).

We currently have:
1. EV
2. Heat pump w/backup heat strip

We want to add:
1. Induction range
2. heat pump or electric water heater

Our current GE breaker panel is essentially out of space. I had a whole home surge protector added when we got the heat pump, which used up the rest of the space we had.

I had a couple electricians look at adding 220 service so we can get an induction range. Because our range is on an exterior wall between the houses, both recommended running conduit on the exterior of the house and drilling through the wall, rather than trying to figure out how to get the wire through the interior walls which would likely require lots of cutting and damage.

The first electrician said we should just replace our entire panel since there's not enough room. The second said he'd recommend adding a sub panel next to it, which is fine under code and will be a lot cheaper. He said we should maybe consider an entirely new panel only if we're getting solar. Getting an entirely new panel is not cheap.

When I had an inspector out to look at the heat pump they said that our 200A service may not be enough if we want to add an induction range and heat pump water heater, but the cost to upgrade to 325+ would cost 15-20k.

Questions:
1. is there any downside to running conduit on the exterior of the house (it's not very visible) to the kitchen for 220 service?
2. Should 200A service be sufficient for the appliances we have (EV, heat pump, heat pump water heater, induction range)?
3. Should I look at replacing the entire panel, or is a sub panel ok?

I remember when 200A seemed like more than enough power, but this inspector has me concerned. He mentioned that we need to do a load calculation, so I'll see if I can find an electrician who will do that.
1. No
2. Without doing a "load calculation" On Your Home". . . .there's no conscientious way to answer this.
3. Load calc lst.
Also, unknown, can you post a pic of your panel, but even then, adding "mini's, etc to make "space" might not be the solution or safe way.
What others have on their home or have done does not apply to what's in your panel and the loads generated in your home.

The inspector is right.
Without doing a "load calculation" for what you have now and your anticipated loads with the changes, there's no way to "know".
It's specific to "your house" only.


Have the electricians do a load count lst. Do it properly per code and safety. Get permits.

j :D
4 subpanels on our mini ranch.
Last edited by Sandtrap on Wed Jul 10, 2024 8:22 am, edited 1 time in total.
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TheGreyingDuke
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by TheGreyingDuke »

A few thoughts:

1) You can share 40 (or 50) amp circuits, in your situation share a line between the induction range and the evse, with priority to the range. It runs intermittently and your vehicle will charge overnight.

2) In Upstate NY, going to 400 amp service puts you into demand charge territory, your rate per kilowatt is based on your peak use during the billing period, best to avoid.

3) There is serious Federal $$ for panel upgrades if you go that route
"Every time I see an adult on a bicycle, I no longer despair for the future of the human race." H.G. Wells
TheGreyingDuke
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by TheGreyingDuke »

TheGreyingDuke wrote: Wed Jul 10, 2024 8:04 am A few thoughts:

1) You can share 40 (or 50) amp circuits, in your situation share a line between the induction range and the evse, with priority to the range. It runs intermittently and your vehicle will charge overnight.
https://simpleswitch.io/

2) In Upstate NY, going to 400 amp service puts you into demand charge territory, your rate per kilowatt is based on your peak use during the billing period, best to avoid.

3) There is serious Federal $$ for panel upgrades if you go that route
"Every time I see an adult on a bicycle, I no longer despair for the future of the human race." H.G. Wells
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lthenderson
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by lthenderson »

MCST wrote: Wed Jul 10, 2024 7:13 am 3. Should I look at replacing the entire panel, or is a sub panel ok?
I've done both ways. At my previous house, the breakers were nearly obsolete and I was having to special order leftovers still in stock from an electrical place in California. So I upgraded to a common one and also upgraded to 200 Amp at the same time. I uninstalled the old box, put in the new box and hooked up all the circuits again. Later I hired an electrician to upgrade the incoming feed and hook the thing up. It was a LOT of work.

So when I moved to my current house and we needed more room, I installed a 100 amp sub panel next to my original 100 amp box. Much much quicker and easier. But I had the room on the wall to do so and the ability to move a few circuits from one box to the other to distribute the loads. This might not be the case in every house.
EricGold
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by EricGold »

Luke Duke wrote: Wed Jul 10, 2024 7:47 am
MCST wrote: Wed Jul 10, 2024 7:13 am The second said he'd recommend adding a sub panel next to it, which is fine under code and will be a lot cheaper. He said we should maybe consider an entirely new panel only if we're getting solar.
This is your answer.
No solar = sub-panel
Solar = new panel
That can be the only answer for small (think 60A or 100A) services. For a 200A service, a smarter and much cheaper approach is a sub-panel that protects the main panel busbar.
JoeJohnson
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by JoeJohnson »

TheGreyingDuke wrote: Wed Jul 10, 2024 8:04 am 3) There is serious Federal $$ for panel upgrades if you go that route
Capped at $600, right?

https://www.energystar.gov/about/federa ... el-upgrade
cmr79
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by cmr79 »

I have more or less all of the appliances you have or are considering (we have an electric resistance stove, not induction along with two electric washer/dryers, double electric ovens) with the exception of backup resistance heating strips as we have a backup propane furnace for our ASHP in a 4000 sq ft home. We also have solar and battery backup. The most electricity we have consumed in a day in the past year is still under 100 kWh...not only are most of these things not going to be used simultaneously, but many won't even be used in the same day. I'd consider getting a smart electrical panel in your situation and not upgrading your service size unless you determine that the 200A service is actually limiting. I imagine you'd need a pretty energy inefficient house or would be running additional high draw items like a hot tub if that were the case, though.
beardsicles
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by beardsicles »

Our 200a panel covers heat pump, EV charger, induction stove, and heat pump water heater with plenty of headroom. I wonder why he thinks 200 will be a problem.
suemarkp
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by suemarkp »

Generally, a 200A service can do an all electric home. The unknowns here that can push you over are:
Do you have strip electric backup heat, and if so how much?
Is your car charger small, like 24A or less, or a big 60A tesla one?

If you have an electric water heater now, a heat pump one will be no different. If gas, then it's a new load.

I would also look for a smaller induction range that will work on a 40A circuit. Some need a 50A.

A load calculation is really the only way to answer the question. If you want to go solar, you probably want a panel with a 225A bus. Some brands use 225A busses in their 150 to 200A panels. Not sure if GE does or not.

You could do the subpanel now and main service later if 200A covers everything.
Mark | Somewhere in WA State
Pdxnative
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by Pdxnative »

I agree with those saying a load calculation is the best bet. But in general 200a service should be sufficient for an all electric home like yours. There are load shedding devices that could be used with your evse circuit if needed (and/or reduce charge amperage with your charger or EV software)

I’d go with the subpanel for now if you have certified electricians recommending that.

If you end up needing a larger panel for solar and battery in the future you can figure it out then and (I think) the panel upgrade might then be wrapped into the project and eligible for the 30% federal credit (double check this). You also might want a smart panel at that point.
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yankees60
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by yankees60 »

When I bought my house in 1982 I had 60 Amp service. Half circuit breaker with the other half glass fuses.

That gave me all I needed.

In 2012 I upgraded to a 100 Amp service. The nice thing about this panel is that it has seemingly endless circuits.

I just went to look at it.

It seems to be able to accommodate 32 total circuits. Currently, half are being used while the other half (16) are unused.

Prime items on it are:

Electric 80-gallon hot water heat pump

Three heat pumps (2-6,000, 1-18,000)

Electric stove

When I've investigated solar in the past they told me that it'd be adequate for solar, telling me that they'd do a sidetap (whatever that is).

I don't know if the addition of the three heat pumps since the last time I investigated solar would affect their analysis today.
Above provided by: Vinny, who always says: "I only regret that I have but one lap to give to my cats." AND "I'm a more-is-more person."
wilked
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by wilked »

Do you have a photo of your panel and your breaker schedule?

Here is my breaker schedule, for instance. Having these would help facilitate the discussion.

You have a 200a service, how many slots in your panel do you have?

https://docs.google.com/spreadsheets/d/ ... sp=sharing
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yankees60
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by yankees60 »

wilked wrote: Wed Jul 10, 2024 1:16 pm Do you have a photo of your panel and your breaker schedule?

Here is my breaker schedule, for instance. Having these would help facilitate the discussion.

You have a 200a service, how many slots in your panel do you have?

https://docs.google.com/spreadsheets/d/ ... sp=sharing
Love it!

I created mine years ago but looking at yours gives me ideas of how to improve it and add more details. Thanks!
Above provided by: Vinny, who always says: "I only regret that I have but one lap to give to my cats." AND "I'm a more-is-more person."
MathWizard
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Re: Electrical questions: 200A service, new panel vs. adding sub panel, exterior conduit?

Post by MathWizard »

It sounds like the sub-panel is the way to go for now until you decide you want solar panels.

I'm not sure why you can't do solar with the subpanel , by moving enough circuits to leave room for a double width breaker.

If the subpanel gets critical circuits, you could get a transfer switch now or later for a generator input as electric backup .
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