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2 Tesla Solar Installs on same roof?

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Does anyone have experience with increasing their Tesla PV system? Tesla is telling me I may have to use two different Tesla logins to monitor the 1st and 2nd system. They're not even promising the two systems will work together, unclear if the old solar will be connected to the new PW.

Are there decent alternatives to the Tesla app to monitor my Tesla PV generation and PW state of charge?

Tesla installed a 42 panel, 2 PW system at my home about 18 months ago. I've enjoyed the system and been amazed at my ROI. We're looking at ways to store excess energy and become less dependent on the grid overnight. We drive 2 Tesla EV's and trying to charge during the day to avoid reliance on the grid has been a headache.

We have an order with Tesla to add 12 panels and 2-4 PWs to increase storage capacity. I made the reservation for this system using my account email, whereas the first system was installed from my wife's account (different email). I was told yesterday the two systems could not be combined into one account and that I would have to cancel and reorder if I wanted to try for that. I was also told he couldn't promise the two systems would even work together, charging each others PW, etc.

Thanks in advance for sharing your experience or advice!
 
This post should likely be in the Tesla energy subforum (at least that would be my recommendation) as you would get much more of the appropriate eyeballs on it there.

I know we have members with more than one system on their home, and they can see them. How it would be connected is not even able to be speculated on, because each install is a construction project. What can see / talk to what depends on (at a high level) what your electric service level is.

If its 200amps or less, you can have one tesla energy gateway (TEG, the device which controls electricity flow) and both systems would work together. If its more than 200 amps, a TEG only supports up to 200amps so you would have to have 2 of them, and then they are two complete different systems that dont talk to each other etc.

However, its possible to have larger than 200amp service but all "backed up loads" be moved to a sub panel thats no more than 200 amps, so it could all work together.

It really depends, which is why Tesla is not able to tell you until a system designer designs your system.

In any case, I would suggest reporting your post and asking a mod for this subforum to move it to the Tesla energy subforum, since this is that type of discussion. I dont have rights here so I can do it (so posting saying "sure move it" is not going to work since I cant). Up to you, however.
 
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I'm located in Hawaii and do not have NEM. I receive a small credit for energy added to the grid that is about 25% of those cost to pull from the grid. I'm primarily focused on retail arbitrage to save money on fuel (home and cars). I currently charge and discharge my batteries 3-7 times a week depending on the amount of sun.

I've also considered Hawaii's new "battery bonus program." Essentially the subsidize about 3/4 the cost of PW in exchange for committing to discharging that PW every day (for 10 years!). Tesla told me yesterday they "do not participate in that program" and that if I signed up on my own I "might void my warranty." I'm going to make that a separate post since its a bit of a side bar to this main topic.
 
In any case, I would suggest reporting your post and asking a mod for this subforum to move it to the Tesla energy subforum, since this is that type of discussion. I dont have rights here so I can do it (so posting saying "sure move it" is not going to work since I cant). Up to you, however.

Outstanding info all around. I have 200 amp service at the home. The sales rep I spoke to was very knowledgeable yesterday. He pointed out that if I go too big (ala 6 PW's) I might trigger an "impedance" test whereby the installer (or electric co?) tests the homes capacity for energy storage. If the house doesn't meet their requirements, they can expect me to upgrade service above 200 amp. His recommendation was to downsize to two PWs.

I'll report the post to have it moved. I was rushing this morning and I guess I grabbed the wrong subforum. Thank you.
 
I had an existing 9.5kW rooftop system, to which I'd added two PW2s about 4 years ago. I recently expanded my system with Tesla by adding 9.5kW more of Tesla-provided panels and two more PWs, one of which is a PW+ with inverter. They are all managed under the same "house" in my single login with Tesla. However, they are having issues getting the installation to work properly. I'm experiencing the following:
  • Inverter shutting down randomly throughout the day, resulting in "spikes and valleys" in my solar generation curve (been on the escalation queue for 3 weeks and was told it'll be at least another 3 weeks before they get to it).
  • Powerwalls cannot figure out how to behave properly with regards to "self-powered" or "time based control." Initially I had it set on the latter, and was told that there is a machine learning algorithm that has to be retrained so I should run on self-powered. Well, that didn't even know how to function and randomly consumed from the grid even when my PWs were full. Still not resolved.
I still haven't paid Tesla for the installation, hoping that this will give me some leverage on getting these issues resolved. It's a little frustrating but at least solar generation is at an annual low. I'd be more upset if we were in July.
 
We originally had Tesla install 16.5 kW (51 panels @ 325W) with 3 inverters and 3 Powerwalls in 2018. In 2019, we were allowed (by our utility) to expand our system so we added another 4 kW (with another inverter) and another Powerwall. We now have 20.5 kW (63 panels), and all are integrated into the same Tesla system and use the same production meter.
 
I put 2 PW on an existing solar installation using a Sunny Boy inverter that supports 3 strings but only had one string running. I added more panels on a second string. The app is handling everything under one Tesla ID. I guess the question for Tesla is whether their inverter can handle multiple strings or if a second inverter can be added with screwing things up.