New Solar/Powerwall Install Colorado Springs, Wait for PTO?

[Yossarian]

My Tesla solar/powerwall installed finished last week. 18kW solar and 2 Powerwalls (Not powerwall+). Two Tesla inverters. Assuming all goes well, it'll be 6ish weeks before I have permission to operate.

My utility, Colorado Springs Utilities, states in interconnection agreement basically that "any grid intertied solar system must be inspected prior to operation". I'm thinking about disconnecting my home from the power grid by pulling the newly installed master disconnect, then powering up my solar. I have enough solar/batteries to run indefinitely off-grid. My thought process is Tesla won't care, because they already checked out the system and tested it themselves, and it changes nothing with them whether my solar is on or off right now. And the utility would care if I was running grid intertied, but I'm not going to do that since it'll be physically connected. Maybe they'll care because of lost revenue because I'll be using no electricity from the utility... What even happens if they find out? Is it illegal or just not technically following all rules?

The catch with my system is that in order for the solar to complete circuit to my home grid I have to raise the lever on this meter connection point. when the lever is down, since there is no meter installed, it's an open circuit. So I can raise the lever to bypass the meter and get my solar operational, but I'm not sure if that bypass is designed for continuous use or just temporary testing.

Thanks for any help

 

[jboy210]

You have to ask yourself whether it is worth any issues you raise.

Also, isn't your system configured to allow solar to charge powerwalls and power your home until the powerwalls are depleted (i.e., reach reserve percentage limit). If so, then the only thing missing is the ability to send excess power back to the grid. I thought that was how Tesla left completed, but none PTOed, solar + powerwall installs.

If there is some sort of meter needed to make it work in this way, I would call Tesla and ask them why and what you are allowed to do pre PTO.

 

[Yossarian]

My system is not configured to allow solar to charge the powerwalls, since I do not have a powerwall+ (I have two powerwall 2s). Tesla said I would be able to operate in self-consumption mode if i had a powerwall+, but that I can't do off-grid mode with what I do have, since off-grid mode could force a grid connection in some instances. But if I pull the master disconnect to the grid, then my system definitely cannot connect to the grid...

 

[crackers8199]

My system is not configured to allow solar to charge the powerwalls, since I do not have a powerwall+ (I have two powerwall 2s). Tesla said I would be able to operate in self-consumption mode if i had a powerwall+, but that I can't do off-grid mode with what I do have, since off-grid mode could force a grid connection in some instances. But if I pull the master disconnect to the grid, then my system definitely cannot connect to the grid...

i'm not sure i understand here...are you saying tesla told you that you can't have just a regular powerwall 2 charge from solar? that's absolutely 100% false, i can vouch for that personally because i just had two powerwall 2s installed on an existing solar system and have no problems charging them from solar.

 

[jjrandorin]

i'm not sure i understand here...are you saying tesla told you that you can't have just a regular powerwall 2 charge from solar? that's absolutely 100% false, i can vouch for that personally because i just had two powerwall 2s installed on an existing solar system and have no problems charging them from solar.

No, thats not what they said. Powerwall+ has a special self consumption mode where the system can run and consume solar without exporting any, prior to PTO. This is only possible with powerwall+, not with powerwall 2.

Its only relevant during this pre pto time.

We also dont know (because this OP has a new solar and powerwall, not just new powerwalls) if there is some meter that needs to be installed, etc.

OP:

If I were you I would simply leave it off, but if you can fully disconnect from the grid to run your system, the utility would only see "no consumption". What you dont want to do, is backfeed anything.

@crackers8199 , a powerwall install onto existing solar is different, because the solar is already PTO'ed / permitted etc. Once the batteries pass the city (AHJ) inspection, PTO from the utility is a formality, IF you have existing solar that was already Permitted and PTO'ed. Since our batteries are not exporting to the utility (just the solar) and you already have PTO'ed solar, you simply have "less" usage than you had before, specifically in your situation.

I added powerwalls onto my existing solar in 2020 (solar existed since 2015) and after the city sign off on the permit, ran them until SCE granted PTO a couple months later. This is different than someone who is getting solar and powerwalls at the same time, because the solar is not permitted. There could be an issue with the tranformer size, etc etc.

 

[crackers8199]

No, thats not what they said. Powerwall+ has a special self consumption mode where the system can run and consume solar without exporting any, prior to PTO. This is only possible with powerwall+, not with powerwall 2.

Its only relevant during this pre pto time.

okay, nevermind then. nothing to see here, move along...

 

[Yossarian]

Oh geez. Big typo. My system IS configured to charge powerwall from solar, but when the tesla installers left they turned the solar system off. The powerwalls are still operational at this time.

Yeah definitely don't want to back feed I agree.

 

[garrett5688]

What I personally did was turn on the inverter, allow the powerwalls to charge up, then turn off the inverter. This at least gave me back up power for any grid outages pre-PTO.

 

[jjrandorin]

What I personally did was turn on the inverter, allow the powerwalls to charge up, then turn off the inverter. This at least gave me back up power for any grid outages pre-PTO.

We are allowed to test the system, and thats always a bit "vague". I would likely do that as well (run solar to charge the powerwalls to 80-90% then turn it off.

@BrettS ran for quite a while off grid while waiting.

 

[BGbreeder]

I am not sure what the photos is, but it looks like a meter base with exposed contacts. If flipping the lever is going to result in those metal contacts becoming live (AC 120/240 voltage), you have a serious safety issue, and liability.

If it what I think it is, I wouldn't do it.

All the best,

BG

 

[Yossarian]

I am not sure what the photos is, but it looks like a meter base with exposed contacts. If flipping the lever is going to result in those metal contacts becoming live (AC 120/240 voltage), you have a serious safety issue, and liability.

If it what I think it is, I wouldn't do it.

All the best,

BG

I think that is what it is. Good point, I'll wait. Not worth the risk.

Thank you!

 

[jboy210]

Your system sounds like ours. We have PW2s, no +. When we were installed, we could not push back to the grid for 4 months waiting for PTO (thanks Covid). In the meantime, I just watched the app and charged the cars when the batteries started to get full. And if we had excess beyond that I shutdown the inverters. The home would drain the batteries in the night and the next morning I brought the inverters back online.

There were a few days where I got busy, and we did send power back to the grid. The utility never said anything about this, and I never brought it up.

 

[yblaser]

Your system sounds like ours. We have PW2s, no +. When we were installed, we could not push back to the grid for 4 months waiting for PTO (thanks Covid). In the meantime, I just watched the app and charged the cars when the batteries started to get full. And if we had excess beyond that I shutdown the inverters. The home would drain the batteries in the night and the next morning I brought the inverters back online.

There were a few days where I got busy, and we did send power back to the grid. The utility never said anything about this, and I never brought it up.

I did the same with my system pre PTO. I think the difference with the OP is that he has a spot for a generation meter with no meter in it thus there is an open connection between the solar inverters and the rest of the system. He could use the bypass switch in the meter housing but I don't think he would be able to put the front panel back on with the bypass lever enabled and there would be exposed 240V out in the open and unprotected.

 

[jboy210]

I did the same with my system pre PTO. I think the difference with the OP is that he has a spot for a generation meter with no meter in it thus there is an open connection between the solar inverters and the rest of the system. He could use the bypass switch in the meter housing but I don't think he would be able to put the front panel back on with the bypass lever enabled and there would be exposed 240V out in the open and unprotected.

OK. If it is the case something is exposed that would not be good. I wonder if Tesla Solar has as a suggestion for this situation. They pretty much showed me which switches to flip pre-PTO.

 

[Yossarian]

Your system sounds like ours. We have PW2s, no +. When we were installed, we could not push back to the grid for 4 months waiting for PTO (thanks Covid). In the meantime, I just watched the app and charged the cars when the batteries started to get full. And if we had excess beyond that I shutdown the inverters. The home would drain the batteries in the night and the next morning I brought the inverters back online.

There were a few days where I got busy, and we did send power back to the grid. The utility never said anything about this, and I never brought it up.

Why not just disconnect from grid and/or use tesla off grid mode? To prevent solar from pushing anything back to the grid.

 

[Yossarian]

OK. If it is the case something is exposed that would not be good. I wonder if Tesla Solar has as a suggestion for this situation. They pretty much showed me which switches to flip pre-PTO.

I could put some duct tape on it (/s)

 

[jboy210]

Why not just disconnect from grid and/or use tesla off grid mode? To prevent solar from pushing anything back to the grid.

I guess I could have done that. But then a stray cloud or high load could have dropped the power for the house. And I was less worried about the power company complaining about me sending them free power, than my wife being mad at me because dinner was ruined when the oven shutdown.