Powerwall 3 cut solar production when it’s near 100% of charge

[smirenna]

Hi, could someone tell me why my Powerwall 3 cut solar production?
I know that when the system can’t put energy to grid it’s normal that the invert cut the power, but now that I can sent
power on grid why il happen?
This is my dashboard today.
Best regards

Santi

[jasonacox]

If you have extended metrics, can you show your alerts panel? It looks like a string went offline.

[smirenna]

Hi, here the data,but it seems to me the strings are ok.

santi

[jasonacox]

Very odd. Alerts seem clean.

[JohnJ9ml]

Do you have your PTO? Until you have permission to send back, your system will just stop the panels as you hit 100%.

[smirenna]

Hi, yes the past week our Energy operator modified our meter in bidirectional. As you can see after I reach the 100% of battery,
the string power decreases but continues to produce and send power to the grid, but the production of solar panels becomes near 3kw from 4.5-5.0 kw

[JohnJ9ml]

Tesla did my install, but I remember there were a series of steps that went on at completion. I got my PTO from the utility extremely quickly - less than 24 hours - and flipped the switch to be able to push back to the grid in the Tesla One app. Three days later I got notification from Tesla that they'd received the approval from the utility as well. However, it still behaved oddly at that point. I watched for a day or two, and nothing seemed to be as I expected it.

I eventually opened up a ticket with Tesla Energy, and they told me they had to take yet another configuration step on their end, and did so rather quickly. They didn't elaborate on the phone at the time. I have since seen - probably in the Tesla One app, I don't think it's in the pypowerwall data - that I'm configured for a cap of 10.9 kw back to the grid. Perhaps there's something permission/configuration-wise still pending on your site, or maybe that cap is set very low on your installation?

I just remember it seemed to go through more hoops than I would have expected once permitting was final.

[smirenna]

Thanks for the advice… I will ask to my installer and let you know.

[smirenna]

Hi everyone,
here’s a brief update regarding the issues I mentioned a few weeks ago:

System data: Powerwall 3 FW 25.2.7 + Tesla Gateway 2 + 5.58 KW solar panel
Issue: The system, configured to operate in self-powered mode, does not export all solar overproduction when the Powerwall reaches 100% charge , instead it limits grid export to a maximum of 3KW.
PTO: Authorization was obtained over 40 days ago.
Ticket: Opened with Tesla on 2025-04-22.
After 15 days without a response from Tesla other than a note saying they had forwarded the issue to the engineering department
I started experimenting with some settings using the official Tesla app.
I discovered that by switching to Time-Based Control and tricking the system into thinking that the price for exporting energy during peak periods was much higher than the purchase price, I was able to achieve solar production up to the maximum output of my panels and export all the energy generated.
Following these successful tests, to prevent the battery from discharging too much during the day, I adjusted the minimum backup reserve percentage to about 10 percentage points below the current battery charge level.
So, if the battery is at 100%, I set the minimum reserve to 90%. This way, the battery powers the house, all solar production is exported, and when the battery reaches 90%, the system maintains the charge at 90% by occasionally drawing some solar production.
Of course, this is just a temporary workaround I found while waiting for Tesla to fix what I believe is a firmware bug.

[jasonacox]

Clever!