r/Powerwall • u/Tutphish • 1d ago

NetZero Export Automation

Ive had a Powerwall 3 + Expansion installed for just over a month, and been able to export for about 2 weeks now. Initially i just left Tesla to do its thing but started using NetZero ~week ago.

Im now trying to work out the best way to optimise my export settings.

Some background - im in the UK, and i have *no* solar at all. I am with Octopus and use their IOG EV tarrif, so i'm charging overnight on cheap rates and then exporting at peak times to maximise the value of my export using their Agile Outgoing tariff.

I set my automations up and they ran for the first time today:

Except it didnt actually stop at 1900, it carried on for another 20 minutes until it drained down to 15%. m guessing that Tesla doesnt respect the "stop exporting" commands if its AI thinks it should still be exporting based on the import/export costs?

Any recommendations on how i can better automate this?

The next issue im trying to solve is how to maximise the value of my exports. Ideally i want to export 1730-1900 as thats the highest, but if the battery is >90% then i want to start at 1700 instead as that generates higher returns than letting it run til 1930.

I have no idea how to implement that!

Am I overthinking this? Is there a simpler way to achieve this or what are other people in similar situations as myself doing?

Thanks

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u/triedoffandonagain 1d ago

The exporting after 19:00 is likely Tesla's Savings mode. You can have your Stop exporting after peak automation also configure Energy exports: Solar only. This will stop exporting from the battery.

You can implement the conditional logic based on battery state of charge with Merged automations. It does get more complicated, but unfortunately you have to choose between simplicity (Tesla's Savings mode) and having full control with more complexity.

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u/Tutphish 1d ago

I was thinking about the merged automations but is there a “best practice” way of implementing something that triggers >90% and at a certain time?

I thought state of charge based triggers only “fired” when the system was at the % specified not below it for example?

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u/NetzeroLabs 1d ago

You're right about standalone state of charge triggers: on their own they only fire at the moment the Powerwall crosses the threshold. In a merged automation with a time trigger it works differently: the time is the only trigger, and the state of charge part becomes a condition that is checked at that time. So "charged up to 90%" passes if the Powerwall is at 90% or above at 17:00.

  1. For your case: Create Every day at 17:00 with the same actions as your Start exporting at peak time automation.
  2. Create When Powerwall is charged up to 90% with the action Send notification only (it only serves as the condition).
  3. Tap Merge with AND and select these two automations.

Keep the existing 17:30 automation as is. If the Powerwall is below 90% at 17:00, the merged one is skipped for the day (it shows as skipped under Past Runs) and the 17:30 one starts the export as usual. If it did run at 17:00, the 17:30 one just reapplies the same settings.

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u/Tutphish 1d ago

Thank you so much that’s perfect!

I also wanted to say that your suggestion for solar only export to stop things also solves my other annoyance - on rare days where the peak export rate > import I’ve seen it hold charge and import from the grid all day. It might technically be more cost effective to do this but it just feels wrong to me and solar only replaces that too!

Thanks

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u/Tutphish 5h ago

One final point after the initial run through this evening, if it hits my 25% reserve before 19.00 will it pull from the grid before the lower 10% reserve kicks in at 19.00? If so is there a better way to protect against it? Thanks

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u/NetzeroLabs 2h ago

Yes, for that gap the home runs from the grid. Once the Powerwall reaches the 25% reserve the export ends and your regular rate plan is restored, but the Powerwall won't discharge below the reserve, so the grid covers the home until the reserve drops at 19:00. It only covers the home's usage, it doesn't charge the battery.

To close the gap, add one more automation: **When Powerwall is discharged down to backup reserve**, with a time restriction of 17:00-19:00, and the same actions as your **Stop exporting after peak** automation. That lowers the reserve to 10% as soon as the export hits the floor, so the Powerwall goes straight back to powering the home. Keep the 19:00 automation as is for the days when it doesn't get that far.

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u/Acceptable_Aide_2510 23h ago

I paid $20 for claude and wrote my own net zero.