Something sounds odd there; if you have solar power charging the PW3 and minimal consumption, the battery ought to charge to (and hold) a full charge until the available solar energy drops below the level of your consumption. At this point, you might well start using the charged PW3’s energy. There are many settings in the Tesla app to control how your Tesla kit behaves; you may care to have a look at these settings to ascertain what is happening. Regards, Toodles.

Just a few settings that I can see.  This is what the installer set:

Are you exporting the solar energy your panels produce? Is your PW set to export from the battery? Regards, Toodles.

Posted by: @toodles

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Are you exporting the solar energy your panels produce? Is your PW set to export from the battery? Regards, Toodles.

Yes I believe so.

@trebor12345 I don't have a Tesla, but my Growatt inverter consumes about 30 wH on standby mode. So, over 5 hours it loses about 1%. In winter, this wouldn't be obvious as our heat pumps are constantly pulling from the batteries and the standby consumption is masked. But, in the summer it's clearly visible. I am not sure how much it's going down each hour in your case as I can't read the image clearly as I am on my tablet and not on a laptop. But this could be one explanation as to why.

@trebor12345 On the home screen of the Tesla app, select the ‘Energy’ option under the picture of the house. You will then have four options, Home, Powerwall, Solar and Grid. At the top right, you will be able to select the time period in which you are interested, Day, Month, Year, Lifetime or Custom. Choose whichever you are interested in and then tap one of the four icons at the bottom for Home, Powerwall etc. At this point you will be able to see the ins and outs and times of power flow. The resolution is rather low but you should be able to determine within an hour or two and within a kWh for the flows. Regards, Toodles.

So this is for today.  The blue line shows the drain to the house over the day.  As the sun has gone down the consumption has increased.  But during the day there is a steady flow of 100 watts (some variation on this).  Interesting to note that the drain stops between 12 and 4, no reason why.  other days show a similar picture, but different times.  Better image attached.

Posted by: @chandykris

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@trebor12345 I don't have a Tesla, but my Growatt inverter consumes about 30 wH on standby mode. So, over 5 hours it loses about 1%. In winter, this wouldn't be obvious as our heat pumps are constantly pulling from the batteries and the standby consumption is masked. But, in the summer it's clearly visible. I am not sure how much it's going down each hour in your case as I can't read the image clearly as I am on my tablet and not on a laptop. But this could be one explanation as to why.

I have attached a better image from today which shows this drain on the battery.  Over the day I am losing at least 20% (2kw) which is quite significant (during solar production).   I can live with the drain, but the battery should be topped up from solar in the day, which its not.  This is Ok for summer, but winter it's more of an issue when you what the max power available.

@trebor12345 20% does sound excessive. Gemini suggests daily standby consumption of around 500 Wh to 800 Wh for a Powerwall, so yours seems to be much more than that. My Growatt inverter is setup to start charging if the SoC goes below 95%, so yours not charging from solar seems odd too. At least you have spotted the issue in the summer months, else the drain would have hidden behind house load consumption from the battery. Hope your installer can give a reasonable explanation and sorts this out.

@trebor12345 Try opening the settings window and then ‘Operational Mode’, at the moment, you are set on ‘Savings’ - swap over to ‘Self-Powered’ mode which should ensure the solar energy when available goes to the battery first and export only when the battery is full or when the Tesla software dictates as it is conserving battery longevity. Once the battery is full, the solar should continue to supply house needs and then export any surplus. Regards, Toodles.

Posted by: @toodles

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@trebor12345 Try opening the settings window and then ‘Operational Mode’, at the moment, you are set on ‘Savings’ - swap over to ‘Self-Powered’ mode which should ensure the solar energy when available goes to the battery first and export only when the battery is full or when the Tesla software dictates as it is conserving battery longevity. Once the battery is full, the solar should continue to supply house needs and then export any surplus. Regards, Toodles.

Switching from Savings to Self Powered, stops the drain on the battery and keeps it at 100% during the day so thats a result.  However, this morning the battery didn't charge overnight!! As of 8am it's now charging from the solar. 

I need the battery to charge overnight at the cheap rate (9p), so I am having to go back to the other setting.

Any other thoughts?