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Second panel / meter - what drives high cost?

Discussion in 'Model S: Battery & Charging' started by spaghetti, May 25, 2013.

  1. spaghetti

    spaghetti Member

    Joined:
    May 10, 2013
    Messages:
    245
    Location:
    Silicon Valley
    For those who got a second panel and meter installed, what drives the high cost? Both PG&E and electricians in California are very quick to point out that a second panel could run into the "thousands of dollars". Thanks in advance.
     
  2. RandyS

    RandyS Fan of Elon

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    Jul 8, 2012
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    Location:
    San Diego
    #2 RandyS, May 25, 2013
    Last edited: May 25, 2013
    If your current service feed is underground, it comes from a local pad-mounted transformer that can be within 4-6 houses. That feed was probably installed when the home was being built, before sidewalks, driveways, etc. So if you'd like to install a new second service, you have to get a permit, duplicate the existing conduit run for the second service, install a second main panel, and run new circuit(s) to your new device(s) as well.

    That would involve trenching all the way to the transformer, 2 feet deep, to install new conduit under driveways, sidewalks, whatever is along the path...Sometimes the path can be "bored" underneath the concrete if it isn't too far, or sometimes the concrete has to be removed and restored later...

    Then once the conduit and new meter / service panel is in place, wire has to be pulled through it and terminated on the transformer and then at your main panel.

    Once your new service is installed, your electrician would then have to run conduit for the branch circuits you want to feed, such as an EVSE for the car and pull wire through that (#2 wire for the HPWC, etc.)

    All of these steps add up, and indeed they can cost many thousands of dollars...

    On the other hand, at SDG&E where I work, we have taken the step of allowing customers to install a second meter "downstream" of the first meter for the EVSE and then we've implemented subtractive billing to isolate the car charging meter read from the primary meter. This assumes, of course, that your main panel has enough capacity for this type of connection. So you don't need the new service feed and the new second panel, etc. but rather just a branch circuit from your existing panel to the new meter socket and then a conduit run with the appropriate wire to your new EVSE installation. But that was a lot of work to set that up as a standard...

    Not sure if it would do any good, but you could lobby your local utility and the CPUC to make that method of connection a standard in your area so customers can save money on car charging installations...It really makes a lot of sense. You can PM me for additional information...

    Thanks, Randy
     
    • Informative x 1
  3. spaghetti

    spaghetti Member

    Joined:
    May 10, 2013
    Messages:
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    Location:
    Silicon Valley
    Thanks, this is a very clear and thorough explanation, and I now understand the reasons behind the high cost for the second panel. The concept of the second downstream meter with subtractive billing is brilliant! I am PM'ing you for more information on this.
     

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