Pics please? If you don't mind what was the total cost before/after incentives?
No pics yet, but I'll get some later on. The nuts and bolts are that I have a main 200A breaker on the side of my house and a single subpanel in a closet inside the house (it's old enough to be grandfathered in, I guess), and they installed the backup gateway next to the breaker, a new subpanel next to the breaker, and then the two Powerwall units on my back deck with a fairly long conduit run. They put 30A breakers for the units in the new subpanel and relocated my existing 30A solar circuit to the new subpanel as well so that it'd be easier for them to stick a CT on it. The installers also insisted on running a hardwired Ethernet line back to my router instead of going by wifi.
Total cost was $13.3k before incentives. I made SGIP tier 1 so if that comes through (it's in "RRF Technical Review" in the latest SGIP spreadsheet), that'll be $9.7k back. I am planning on collecting ITC as well, though I am trying to figure out how best to collect the data for that. (Doing the math there shows the $9.7k to be a bit more than 70% of the system price, so I'm not sure how that's going to work out, since if I claim the full 30% on ITC, I'll actually come out ahead once everything shows up, and that doesn't sound right.)
Observations from playing around with the system:
- The app lets you set backup only or self-powered mode. Self-powered mode has you set a minimum battery level that the system maintains unless there's an outage. If you're above the minimum level, it charges off solar only, but if you're below, it charges off the grid as well. Backup only seems to be like self-powered mode set to 100%, so that it charges off everything and then never depletes it.
- Self-powered mode has only charged my batteries to 90% max. No idea if this is a new system break-in thing.
- On the first day, my batteries were only charged at 3.3 kW. This wasn't that hot a day, and I saw higher rates yesterday when it was really hot, so I suspect that's another break-in thing.
- The app gives you nice graphs showing instantaneous and historical power distribution between house, solar, battery, and grid. It also reports outages, which is how I know that yesterday, I had two outages of 7 and 10 seconds. I guess the graphs and associated data are intended for SGIP/ITC proof later.
- The backup gateway provides a small web server on the network it's connected to. Right now, it just shows the same instantaneous power distribution picture that the app does; nothing more from my point of view. It provides an installer wizard, but fortunately, it demands an installer e-mail and password in some kind of manual, so you can't go messing with it. If you're technically minded, you can sniff the traffic when the power distribution page is up, and you'll see that the unit provides a surprising amount of info via JSON, so you could probably grab that and do fun things with it.
(edit) I see I misread and that I can only collect ITC on the net cost after SGIP rebate. That makes more sense. However, as you can see, the proposed rebate value on my system is still over 70%. I do kind of wish I'd opted out of ITC this time around, but I haven't done enough of an analysis to have a full opinion.