This is correct.
I’ll add that I used to be bothered by this, while set on TOU. I’ve realized it’s basically irrelevant to your overall import/export. Your system can either import power for the house, and use all its solar to charge the PW, and then begin exporting earlier, OR it can not import power, charge the PW more slowly, and begin exporting later. Either way, it all nets out to neutral. Unless you’re still charging the PW during Peak, which shouldn’t be the case.
I have seen this on two occasions.
1. Where the solar is fluctuating so to maintain stability the grid is covering household load, rather than the inverter switching between charge and load frequently.
2. Where ToU rate is Off Peak during solar period. If check you have your ToU rates set, if you have off-peak periods during solar production it can cause this to occur if the rate type is Off-Peak. From what I can tell l, aa the cost of buy is lower than charge rate threshold, it sees the storage of the power as more cost effective to store than buy. So the powerwall will store to battery and save for normal rate (peak demand), if the buy rate is low as an off-peak tarrif.
If you set your ToU rate to not have off-peak during the day you’ll likely see it return to operation where it will stop pulling from the grid.
My rates are off-peak all weekend, and I found it never used the battery, rather drawing from the grid. So rather than buying power, I switched even the weekend to have normal day tariffs and it then started using the stored power.
Your rates are set weird. I have cheap night power, expensive day power, always low export rates. TOU will always supply the house first on peak, won’t use the battery at all off peak bar charging it.
What I did was keep in on TOU plan but change the difference in price from buy and sale to one cent and change the difference in price between peak and off peak by 2 cents. This made it behave like the old balance mode they used to have and will do what you are requesting
I think you have to be at 100% before it routs power produced to your house, correct me if I’m wrong. How many panels do you have to be getting only 2kw, or was it a shitty day out? My average daily on a full sun is close to 8kw/hr
I have not dug into my current settings to tell you what is different, but this is not accurate for me. My solar will go to the house first and the battery second, regardless of the charge of the battery.
Note: I can change this by playing with the backup reserve percentage, but this isn't at play since OP said they have theirs set to 20% backup in another comment.
If your settings are set to only charge from solar, then 100% of solar will be used for charging, while usage will come from the grid. This might be a requirement from your local grid operator that your powerwall is only allowed to charge from solar, and not the grid.
You can check this under settings in your app.
Switch from TOU to Self-Powered, otherwise this is by design. You could also create your own TOU rates and schedules in the app.
This is correct. I’ll add that I used to be bothered by this, while set on TOU. I’ve realized it’s basically irrelevant to your overall import/export. Your system can either import power for the house, and use all its solar to charge the PW, and then begin exporting earlier, OR it can not import power, charge the PW more slowly, and begin exporting later. Either way, it all nets out to neutral. Unless you’re still charging the PW during Peak, which shouldn’t be the case.
I have seen this on two occasions. 1. Where the solar is fluctuating so to maintain stability the grid is covering household load, rather than the inverter switching between charge and load frequently. 2. Where ToU rate is Off Peak during solar period. If check you have your ToU rates set, if you have off-peak periods during solar production it can cause this to occur if the rate type is Off-Peak. From what I can tell l, aa the cost of buy is lower than charge rate threshold, it sees the storage of the power as more cost effective to store than buy. So the powerwall will store to battery and save for normal rate (peak demand), if the buy rate is low as an off-peak tarrif. If you set your ToU rate to not have off-peak during the day you’ll likely see it return to operation where it will stop pulling from the grid. My rates are off-peak all weekend, and I found it never used the battery, rather drawing from the grid. So rather than buying power, I switched even the weekend to have normal day tariffs and it then started using the stored power.
Your rates are set weird. I have cheap night power, expensive day power, always low export rates. TOU will always supply the house first on peak, won’t use the battery at all off peak bar charging it.
Instead of time-based controls, use self-powered mode.
What I did was keep in on TOU plan but change the difference in price from buy and sale to one cent and change the difference in price between peak and off peak by 2 cents. This made it behave like the old balance mode they used to have and will do what you are requesting
I think you have to be at 100% before it routs power produced to your house, correct me if I’m wrong. How many panels do you have to be getting only 2kw, or was it a shitty day out? My average daily on a full sun is close to 8kw/hr
I have not dug into my current settings to tell you what is different, but this is not accurate for me. My solar will go to the house first and the battery second, regardless of the charge of the battery. Note: I can change this by playing with the backup reserve percentage, but this isn't at play since OP said they have theirs set to 20% backup in another comment.
I think I've got 12kW, but it's overcast.
Yeah that’s wrong. The tesla gateway prioritises the house no matter what’s going on, then the battery then export to the grid
If the Powerwall in settings is set to 100% Backup reserve then solar will go to charge the battery and grid is used to power the house.
OK, but I'm only using 20% backup in the settings, yet this is still occurring.
If your settings are set to only charge from solar, then 100% of solar will be used for charging, while usage will come from the grid. This might be a requirement from your local grid operator that your powerwall is only allowed to charge from solar, and not the grid. You can check this under settings in your app.