Another Powerwall + Solar + Grid question

[NYUES88]

Alrighty so we are in the process of getting solar and 1 powerwall from Tesla. And this is the conversation between Tesla rep and us today. It is my understanding that you cannot charge from the grid with solar (unless in storm watch). I am hearing from Tesla that I can charge from grid with solar installed. On the forums I read everywhere that I can't. What am I missing here.

Tesla rep to us:
Good afternoon,
The Powerwall can charge from the gird with or without solar. The preferred method is solar during the day to charge the Powerwall at no cost.
The Vest period would depend on your utility provider. Most providers will allow you to charge the power wall from the grid whenever there isn’t solar or you set the setting to charge from the grid (all is done on the app).

Us to Tesla rep:
So just to clarify, our utility company is PGE , we are getting Tesla solar panels and Powerwall installed and will be taking advantage of the ITC. So you are saying given all that info we would be able to charge our Powerwall from either our solar or from the grid from day 1 of the system up and running? We just want to be sure since this makes our payback period especially for the winter months more favorable.

Tesla rep tp us:
Yes, PG&E will allow the powerwall to charge from solar and the grid from day 1. Power wall will pull from the solar first then from the grid

 

[Sonus]

When you have Solar configured in the app the PW will NOT charge from the grid. unless in storm watch.


Combining Systems | Powerwall Support

Powerwall & the Grid
When Powerwall is installed without solar, it can charge from the grid if in Backup-only or Time-Based Control to support you during grid outages and to help you save money on your electricity bill. When Powerwall is installed with solar, it will not be able to charge from the grid.

 

[NYUES88]

Thank you Sonus,

I have recited that line to two Tesla reps now, and both said I can charge it from the grid. You can understand my absolute befuddlement.

 

[ACarneiro]

Hmmm.... This is not my understanding of how it worked and very much changes everything about my plans for solar and PW.

Where can we get authoritative answers to this question?

 

[mattack4000]

Also the PW won't be eligible for the federal tax credit if it is not charged from solar with 80%

 

[jjrandorin]

Hmmm.... This is not my understanding of how it worked and very much changes everything about my plans for solar and PW.

Where can we get authoritative answers to this question?

There is one person here (in arizona) who got an exception from his utility to be able to charge from the grid when not in storm watch mode.


They are incorrect, as it relates to having solar + powerwall.... or you will be the only person in the bay area on PGE who has solar + powerwall and gets PTO for charging your powerwall from the grid WITH solar. Tesla doesnt even configure it that way so not sure what they are telling you.

 

[Raechris]

No grid charging of PW in MA.
No tax credits if charging PW with grid.
No solar power when grid out unless have PW

 

[ACarneiro]

Ah, may be a specific T&Cs issue in the US (which may not apply in Europe) rather than a technological limitation then...

 

[Watts_Up]

No grid charging of PW in MA.
No tax credits if charging PW with grid.
No solar power when grid out unless have PW

I guess it's why all those salvaged Tesla get their batteries removed before getting sold for auction.
- I imagine then that those batteries then might be converted into homemade Powerwall?

I calculated that if I was connecting my appliances to an homemade Powerwall during pick hours.
And then if I was charging my homemade Powewall, and also connected my appliances, during off peak, to the grid.
In average my electricity bill would drop by 40% (I mad assumption that the AC/DC and DC/AC was 85% efficient.)

I would be interested knowing the cost of making an homemade Powerwall to estimate how long it would take to make it profitable...

 

[bob_p]

No grid charging of PW in MA.
No tax credits if charging PW with grid.
No solar power when grid out unless have PW

Also add that charging from the grid (except for storm watch) will also change the PowerWall warranty, with a limit of how much charging will be included under the warranty.

 

[aesculus]

Ah, may be a specific T&Cs issue in the US (which may not apply in Europe) rather than a technological limitation then...

Yes. It is supposedly an agreement with Tesla and the US government that allowed solar + pw to claim a government tax credit without having to log their power distribution everyday and report this on their taxes. Makes it easier for us.

I would expect that non US installs don't have this restriction and I know it does not apply to AU for example.

The exception for the AZ person was a bit different. They were able to demonstrate that even grid power was renewable and therefore the restriction was moot. Calif for example still consumes a lot of natural gas to generate power.

 

[jjrandorin]

Ah, may be a specific T&Cs issue in the US (which may not apply in Europe) rather than a technological limitation then...

Yeah this discussion is US Based. From reading here, I believe it is different in various places in Europe etc, but "charging from the grid" is definitely not a "technical" limitation as far as the powerwalls go. Even in the US, if you DONT have solar, you can charge your powerwalls from the grid (but forgo any credits on your taxes), and you can only export up to the amount of energy you consume, at least thats my understanding.

Most people here pair the powerwall with solar, unless they either have an extreme issue with power outages (and somehow dont benefit from solar), or got the powerwall for "free" as part of the tesla referral program that offered those back in the day.

 

[NYUES88]

Thank you all for your replies, I sent the Tesla rep a link to both the forums and Teslas website stating it cannot charge from the grid and asked for confirmation from another rep. I really feel Tesla reps are wrong, it's just somewhat annoying that customers know more about the product than actual reps. It doesn't change the payback period drastically, but I just want to have a correct and complete picture of the project and Tesla flip flopping is making that difficult.

 

[jjrandorin]

Thank you all for your replies, I sent the Tesla rep a link to both the forums and Teslas website stating it cannot charge from the grid and asked for confirmation from another rep. I really feel Tesla reps are wrong, it's just somewhat annoying that customers know more about the product than actual reps. It doesn't change the payback period drastically, but I just want to have a correct and complete picture of the project and Tesla flip flopping is making that difficult.

/shrug... I would ask them to send you, in writing (not email) with their name attached to it, on Tesla letterhead, that "yes, your powerwall will charge from the grid at times of your choosing when connected to either existing, or newly installed, Solar panels / roof".

There is like a <1% chance that someone would actually send you that letter, because it contradicts everything we all have experienced with our own US based installs.... but if they DO, then you would have a reason to go after tesla to activate that on your OWN installation should you choose to do so.

Hopefully you are talking to a US based agent, and they know you are also in the US, because as also stated on this thread, rules are different outside the US on this topic.

 

[NYUES88]

I feared I was not talking to a US based rep as well, thats why I cited that I was a PGE customer and that I would be taking advantage of the ITC so they had a complete picture of my personal situation. And he literally said "Yes, PG&E will allow the powerwall to charge from solar and the grid from day 1. Power wall will pull from the solar first then from the grid" I will ask for another reps confirmation and if that one comes back saying that I can charge it from the grid then I will ask for it in a written agreement. Thank you

/shrug... I would ask them to send you, in writing (not email) with their name attached to it, on Tesla letterhead, that "yes, your powerwall will charge from the grid at times of your choosing when connected to either existing, or newly installed, Solar panels / roof".

There is like a <1% chance that someone would actually send you that letter, because it contradicts everything we all have experienced with our own US based installs.... but if they DO, then you would have a reason to go after tesla to activate that on your OWN installation should you choose to do so.

Hopefully you are talking to a US based agent, and they know you are also in the US, because as also stated on this thread, rules are different outside the US on this topic.

 

[cwied]

Tesla's training of their reps (sales and support both) seems to be substandard. The ITC specifically precludes charging from the grid - that has nothing to do with Tesla. You can only get the tax credit for the batteries if they are charged solely from an onsite renewable source (i.e., solar in this case).

Also, except for that one case mentioned above, I have not heard a single US Powerwall owner in this forum say that they were able to charge from the grid (except during Stormwatch events). For sure my Powerwalls will not do that.

 

[mattack4000]

They are solar salespeople, I think you have to put that in perspective......

BTW, I didn't know about the storm watch. So whenever Tesla throws out storm watch alert, they allow you to charge from the grid?

 

[roblab]

Alrighty so we are in the process of getting solar and 1 powerwall from Tesla. And this is the conversation between Tesla rep and us today. It is my understanding that you cannot charge from the grid with solar (unless in storm watch). I am hearing from Tesla that I can charge from grid with solar installed. On the forums I read everywhere that I can't. What am I missing here.

I have had 3 powerwalls for about a year now. They charge from the grid, if need be, or from solar, which I also have. The solar also feeds into the grid if powerwalls are full, but generally the powerwalls charge during the day and run my lights and house all night. So, yes, you CAN charge from grid with solar installed. I am also charging my car right now (10 AM) with solar, powerwalls and grid. My car will absolutely drain the powerwalls (100 kwh car vs 20 kwh PW) so of course it will use PW first, then switch to grid. Then solar will sell to grid to pay back what I'm using this morning.

Hope this is confusing enough. Powerwalls are pretty smart. BTW, I'm on Self-powered with PW minimum of 10%. Seems we hardly ever have a PG&E bill; usually it's a payback because I make more than I use.

 

[jjrandorin]

I have had 3 powerwalls for about a year now. They charge from the grid, if need be, or from solar, which I also have. The solar also feeds into the grid if powerwalls are full, but generally the powerwalls charge during the day and run my lights and house all night. So, yes, you CAN charge from grid with solar installed. I am also charging my car right now (10 AM) with solar, powerwalls and grid. My car will absolutely drain the powerwalls (100 kwh car vs 20 kwh PW) so of course it will use PW first, then switch to grid. Then solar will sell to grid to pay back what I'm using this morning.

Hope this is confusing enough. Powerwalls are pretty smart. BTW, I'm on Self-powered with PW minimum of 10%. Seems we hardly ever have a PG&E bill; usually it's a payback because I make more than I use.

I think you are confusing the original question. Yes, you can charge your car from the grid when you have solar and powerwalls,

you can NOT ""refill the powerwalls" with charge coming specifically "from the grid". You refill your powerwalls with your solar power, not with power from the grid, unless in stormwatch mode.

 

[jjrandorin]

They are solar salespeople, I think you have to put that in perspective......

BTW, I didn't know about the storm watch. So whenever Tesla throws out storm watch alert, they allow you to charge from the grid?

You turn on stormwatch mode (which allows the powerwall to charge from the grid IF tesla activates stormwatch in your area). If tesla activates a stormwatch, your powerwall will automatically fill itself from the grid (+ solar if solar is available).