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Community and Q&A

Ballpark — Cost to upgrade to 400 amp service

t_smith | Posted in Webinar Follow-up Q&A on

We’re in Midcoast Maine using CMP and would like to upgrade our electrical service from 200 amp to 400 amp. I was shown a quote for $26k. I had thought that this could be done for no more than $10k. Job is straight forward, easy <40′ to service pole. Has anyone done this recently in ME and can share costs?

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  1. Expert Member
    BILL WICHERS | | #1

    Is that number from your electrical contractor, or for the utility? Here's what's actually involved for both:

    For the contractor: Larger wire from the meter can to the pole/pedestal, and from the meter to the panel. A 400A panel is needed too, although it's more common to use multiple 200A panels instead, in which case the panels cost the same, you just have more of them. Labor is a bit more with the heavier cabling, but not much. I would expect a premium for 400A service to be a few thousand dollars or so on a new build, as compared to a more common 200A service. This does depend a bit on the length of cable runs involved though. For an upgrade, you have to replace everything, so that ~$10k number might be close, depending on what is involved and the difficulty of the work. It's a lot more work to replace a panel recessed into a finished wall, for example, than it is to replace one mounted on the surface of a foundation wall in an unfinished basement.

    For the utility: Beefier meter and meter base. These are often provided free on a new build though, might be added cost items for an upgrade, depending on the utility. They will probably replace your transformer with a bigger one -- THAT is where their largest cost is likely to be. They MIGHT (doubtful though) also do some rerating of their primary system (the high voltage lines) to support the larger service, but I kinda doubt that will be necassary on a residential service. Even 400A residential service is pretty small for a typical primary circuit for the utilities. In my area, a fully loaded 400A service is about 0.9% of a typical primary circuit. Not much.

    If the $26k number is a combined total for everything (utility AND indoor contractor work), it might not be too far out of line. There can sometimes be ways to lower those costs though, but you haven't provided enough info to be able to give you any ideas in that regard.


  2. t_smith | | #2

    Bill -- Very helpful, thanks.

    Electrician has been in contact with the utility so I've assumed this is utility cost + contractor cost.

    Meter is located on exterior garage corner with the main panel located on the interior garage wall behind the meter location.

    This is new construction but on our second builder. Electrical service was not well considered initially despite project being well defined. Besides typical residential use, we also are constructing a licensed small dairy (our third) which at previous locations has consumed around 10kw-hrs/yr (pasteurizer, refrigeration, lots of hot water use). The house is all electric, and it looks hard to meet peak demand on a 200 amp service. We wanted to use on-demand water heating, but this upgrade cost may nix that. A second 200 amp service for farm use would have been easiest but CMP wants a single meter.

  3. walta100 | | #3

    General a 320 amp meter base will feed twin 200 amp panels gets call a 400 amp service often.

    From what I understand both the meter bases and the panels are in short supply and the waiting list is often several months long.


  4. walta100 | | #4

    Farms maybe different be generally for a business you would want its loads on a second meter for businesses so you can deduct the costs on your taxes. Also, the rate structures are often different. There is likely a set of rules for farms I know nothing about.

    If you will have a lot of refrigeration and motors for the dairy it may cost less to operate if you buy 3 phase equipment and get 208 volt 3 phase service.


  5. Expert Member
    BILL WICHERS | | #5

    There are a MAJOR issues getting multi-meter bases right now. I've run into that a number of times over the past year. I haven't had any problems getting 200A panels though. Meter base lead times shouldn't change the cost of the projects though, it will just mess up your schedule.

    Walta is right that your commercial venture may find things easier going if you go with either a Farm rate 120/240V service, or a commercial standard 120/208 or 277/480 three phase service. I don't know if the power feed will necassarily save you money, but the commercial rate (which is usually lower per kwh) probably will.

    I would avoid electric tankless water heaters. If you want tankless, go with natural gas (if available) or propane. If you want electric heating, use a tank-type water heater.

    For your electrical install, try using multiple 200A panels fed from a common meter base (if allowed), or use a 400A panel with 200A breakers to feed those other panels. Even an all-electric home should be OK with a 200A panel though, as long as you aren't trying to put in an electric tankless water heater.


  6. t_smith | | #6

    Bill and Walta -- Many thanks for taking time to comment. At a one old location, we did have separate service for the farm business and at another we just added a submeter to be able to ascertain business usage. Since we have propane for a backup generator, we will think about that for tankless water heating -- we've done that in the past, too.

  7. Eric_U | | #7

    I haven't seen my bill yet, but I'm currently in process of getting 400a (320 continuous) service for my new house and your numbers seem really high. I'm doing a lot of the work myself though, so that is part of it. On my own math, a day rental of a trencher is $300, 4" schedule 80 is $10/ft, 5oomcm is $1.50/ft I think, and my power company gives out the 400a boxes for free, so that's nice. You can do the math for you distance and figure out how much mark up they are charging you but I'm expecting just a few thousand bucks, most of which is the PVC. You could also do parallel risers in which case you could use 1/0 wire in 2" schedule 80, but obviously you'd need the materials x2 in that case so not sure if it would actually save money. Like others are saying, 200a meter boxes are in short supply right now, my power company told me there was a 4-6 week back order, and you'd need two so I would stick with the single 400a box and single riser

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