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powerwall clarification

Discussion in 'Tesla Energy' started by novynova, Oct 11, 2017.

  1. novynova

    novynova Member

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    can anyone clarify something for me- does the powerwall ONLY power the subset of circuits that they put on a separate panel or does it cover the whole house (assuming the usage is below capacity)?
     
  2. dhu1

    dhu1 Member

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    your choice....you have to tell Tesla what you want and have the appropriately sized storage for each use case
     
  3. miimura

    miimura Active Member

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    You can think of it two ways:
    1. When the grid is up, the Powerwall can offset all your usage and drive your utility meter to zero consumption.
    2. When the grid is down, only the circuits inside the gateway transfer switch will be powered.
     
  4. novynova

    novynova Member

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    Thank you!!! #2 was me exact question
     
  5. Shygar

    Shygar Member

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    For me, Tesla would only do a whole house backup if I bought 2 or more powerwalls. For one powerwall only, they won't do the whole house. For my case it worked that my entire house minus my AC was on a subpanel already, so I got what I was looking for.
     
  6. novynova

    novynova Member

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    I'm in the same boat except swap your AC for my Electric stove. i would understand more if my typical usage wasnt so paltry. I typically use 12ish kwh a day which the powerwall site says should more than be covered by a single unit
     
  7. Shygar

    Shygar Member

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    Yea and I'm guessing some of that usage will be offset by solar during the day. The other thing they told me is I can only run 30 amps at one time. Feels like if I run the microwave and the dryer together I'm gonna go over that right? I haven't tried to do that yet
     
  8. novynova

    novynova Member

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    I know. I just can’t justify the cost of a second Powerwall. Maybe one day
     
  9. AnOutsider

    AnOutsider S532 # XS27

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    Sorry to bump this, but had a relevant question before cancelling my powerwall. I was told at the site survey that they can NOT backup more than one panel, so I had to choose a single panel that had the most useful things on it (and was told it didn't matter how many I bought). Truth?

    Also, after the survey, I got an email saying they can't handle 3 phase? I'm not at all technical when it comes to electrical components and terminology, so maybe it's best I just share what was relayed:

    That make sense? Without knowledge I can't think my way around that, and while the guy probably knows his stuff, I've gotten incorrect information from Tesla employees more than once, and want to ensure there isn't some misunderstanding/miscommunication before I authorize them to do the refund.
     
  10. wwhitney

    wwhitney Member

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    It is always possible Tesla has a policy that is more limiting that what the technology can do. But technology-wise, what you need to do is to pick a point on the electrical system graph and install the Backup Gateway there. Everything downstream of the Backup Gateway would be backed up; everything on the utility side of the Backup Gateway would not be.

    So if you want to back up two panels, you can find a point upstream of both to put the Backup Gateway. But depending on how the rest of the electrical system is wired, this could lead to having other panels on the wrong side of the Backup Gateway, i.e. backed up when they can't be. That would mean rerouting some feeders to move the other panels to the utility side of the Backup Gateway. [Or rerouting feeders to create a point in the system to put the Backup Gateway that backs up only the desired panels.]

    The other limitation is that if you install k Powerwalls, then Tesla doesn't want you to have any branch circuit breakers in your backed up panels larger that 30*k amps. This roughly accounts for the power output limitations of a Powerwall. So that could mean rerouting some branch circuit wiring.

    Cheers, Wayne
     
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