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Powerwall control

I have searched for this elsewhere, but cannot find an answer. I have a PV system installed and a power wall on order.
I read on a different forum that the power wall would take all available surplus power until it was at 100%. Is there anyway that I can set or program it give priority to charging the car and then only charging the powerwall after the car is full unplugged?

The reason wanting to do this is reduce what we export to grid. In the summer here is gets light at 5:00 am and the sun is well and truly up by 6:00 am (on days that it is sunny that is). At around 9:00 my wife takes the car out. I can see a situation where the sun comes up, charges the powerwall, and then the rest of the morning we export to the grid as the gone is gone and there is nothing else to charge. It would be better to charge the car until it goes out and then charge the powerwall after.

Most of our panels are orientated to the South East, so morning is our peak charging time.
 
Not 100 % if it is same system behavior in Uk as the states but I essentially do what you are stating, I believe. I am also assuming your ev is a Tesla.
My system is set for self powered .. when sun rises I may have from 75 down to 50% in powerwalls depending on night use. I start charging car when sun is up and I am generating at least 2Kw from solar (before pw can fully charge up). The car will draw much more than the solar can provide so will also draw from pw(s) but not so much so as to need grid power. This will continue until either car charges to level you set it or power wall(s) hit their reserve level you set (then system will begin charging your car from only solar or solar / grid depending on your settings this part I‘m not completely sure of since I do not let pw hit reserve in this situation.)
Then after car charging complete system will continue to charge powerwall(s) and run house rest of daylight hours.
Basically I am using excess pv production each day to charge ev before pw can fill up and it exports to grid ... I believe there is way to do this automatically in pw settings but have yet to have access to app due to tesla issue. So requires manual effort on my part.
 
Thank you. That is exactly what I want to achieve.
Yes, my EV is a Model S.
My charger has a setting which will allow it to charge at minimum rate (1.4 kw) unless the solar is providing more than that, in which case it will match the solar. Starting that as soon as I wake up, or even using the timer on the car to start it just after sun rise, may be a good solution.
If there is a setting in the powerwall app that allows this to happen without manual intervention every morning then so much the better.
 
Thank you. That is exactly what I want to achieve.
Yes, my EV is a Model S.
My charger has a setting which will allow it to charge at minimum rate (1.4 kw) unless the solar is providing more than that, in which case it will match the solar. Starting that as soon as I wake up, or even using the timer on the car to start it just after sun rise, may be a good solution.
If there is a setting in the powerwall app that allows this to happen without manual intervention every morning then so much the better.
i believe there is a setting in TEG (compenent needed w/ power wall) that allows you to set tesla ev to start charge when powerwall at 90% .. not sure if can adjust this as this is based on what i have read here since i still do not have access to app :rolleyes:
 
The Powerwall doesn’t have a setting, but you don’t need one. Since if your car starts charging and your Powerwall is in self-powered mode instead of backup only, then the power is drawn from solar, Powerwall, or grid in that order (you can still set a backup reserve percentage of you battery in self-powered mode).
Just make sure you charging your car at a rate lower than the total generation of solar as you indicated and you can do exactly what you want by setting the car to start charging when the time you think your solar is generating.
 
i believe there is a setting in TEG (compenent needed w/ power wall) that allows you to set tesla ev to start charge when powerwall at 90% .. not sure if can adjust this as this is based on what i have read here since i still do not have access to app :rolleyes:
Not quite. The setting in the TEG is the percentage of your Powerwall the car will use to charge IF there is a grid outage.
It’s a safety setting to make sure you don’t drain your Powerwall into the car if you are charging and the grid goes out.
 
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I don't think there is a minimum... I've seen 0.1 kW charging my PWs
It fluctuates greatly as the PV and home loads vary.
i agree no min ... i just used 2kw as example powerwall will charge with any amount of pv beyond what home demands at moment ..(this included ev charging lumped in with house use) i have also seen 0.1kw going to my two powerwalls .. this of course does almost nothing to charge them
 

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