Tesla Motors Club

Finally getting my solar with single Powerwall 2 installed tomorrow. Over the last several months while I have waited patiently, along with everyone else, to get my system; I have been thinking that I should have gone with a two Powerwall installation to begin with. (My limited thinking was to go with a simple backup solution and, more importantly, have the ability to used my solar panels when the sun was out and the grid was down.)

Rather than make a change at this late date (permitting, etc.), has anyone out there added an additional Powerwall after the fact? If so, is it as simple as I seem to think it might be? I don't plan to change from powering the secondary panel and go whole house, just want to increase coverage time for outages.

Cheers,
James