Tesla Says I Can Only Get *ONE* Powerwall bc of my Utility's Rules

[stagepuppy]

I'm hanging an off-grid/grid assisted inverter with it's own 8KWdc solar along with a bunch of server rack batteries to it's own load center that will serve to power a garage a/c mini split and a near future BEV. Since there is no export, there should be nothing different from the utilities' measurements and the current Tesla installed solar/powerwalls/gateway would see it as another load when it runs in grid assisted mode.

The inverters and batteries can also be paralleled so the system can be augmented as needed.

The products indeed are out there in droves and improving very quickly. Problematic items have fallen out of favor and the manufacturers of products getting good reviews have been receptive to comments from YT and other early reviewers. Time will tell how successful these items will be, but the quick product improvement cycles are very welcome to the DIY crowd.

Not sure if I can mention the products and other web forums by name... question to the Mod, please advise...

 

[cali8484]

I'm hanging an off-grid/grid assisted inverter with it's own 8KWdc solar along with a bunch of server rack batteries to it's own load center that will serve to power a garage a/c mini split and a near future BEV. Since there is no export, there should be nothing different from the utilities' measurements and the current Tesla installed solar/powerwalls/gateway would see it as another load when it runs in grid assisted mode.

The inverters and batteries can also be paralleled so the system can be augmented as needed.

The products indeed are out there in droves and improving very quickly. Problematic items have fallen out of favor and the manufacturers of products getting good reviews have been receptive to comments from YT and other early reviewers. Time will tell how successful these items will be, but the quick product improvement cycles are very welcome to the DIY crowd.

Not sure if I can mention the products and other web forums by name... question to the Mod, please advise...

Did the off-grid system require permit and inspection?

 

[stagepuppy]

Did the off-grid system require permit and inspection?

This originally began with an inquiry to the LA City D of Building and Safety to construct a driveway awning that could serve as a solar panel mounting surface, and they told me that unless my garage was converted into a living space, I could not build a structure in the front of the house. I was already heading down the road with DIY since Tesla will not install solar on such a structure. The engineer I spoke with said that I could build such a structure in my backyard without any permits needed, which was surprising as I thought permits were generally needed for patios.

In further research for the DIY, I'd been looking at hybrid inverters, but this recent incarnation of a split-phase capable off grid inverter, much improved over a previous model, along with many respected DIY personalities doing installations and tests, with it's unbeatable price, started me down this road.

As I've mentioned, I've taken to heart the advice that many pros on this board as well as other boards, provided so I keep to the most stringent standards to limit my risk. That is by far, is among most important things I've gained on this board.

The Tesla Solar and Powerwall system has served me well so far, but after they did much of the pioneering work and sales model, it would only be inevitable that DIY industries would appear to allow DIYers to do it at a more attractive price point. It's been in spurts, and some not so good, but I think it's maturing into something of great value for your everyday DIYer -- it's not for everyone, but for those who decide to educate and inform themselves to being comfortable enough to try it, it's a great satisfaction of being able to do it right.

 

[Vines]

This originally began with an inquiry to the LA City D of Building and Safety to construct a driveway awning that could serve as a solar panel mounting surface, and they told me that unless my garage was converted into a living space, I could not build a structure in the front of the house. I was already heading down the road with DIY since Tesla will not install solar on such a structure. The engineer I spoke with said that I could build such a structure in my backyard without any permits needed, which was surprising as I thought permits were generally needed for patios.

In further research for the DIY, I'd been looking at hybrid inverters, but this recent incarnation of a split-phase capable off grid inverter, much improved over a previous model, along with many respected DIY personalities doing installations and tests, with it's unbeatable price, started me down this road.

As I've mentioned, I've taken to heart the advice that many pros on this board as well as other boards, provided so I keep to the most stringent standards to limit my risk. That is by far, is among most important things I've gained on this board.

The Tesla Solar and Powerwall system has served me well so far, but after they did much of the pioneering work and sales model, it would only be inevitable that DIY industries would appear to allow DIYers to do it at a more attractive price point. It's been in spurts, and some not so good, but I think it's maturing into something of great value for your everyday DIYer -- it's not for everyone, but for those who decide to educate and inform themselves to being comfortable enough to try it, it's a great satisfaction of being able to do it right.

Despite the awning itself being allowed to install without a permit, I am 100% sure they would have a totally different view of the fire and electrical risk of an unpermitted and uninspected 8 kW PV and ESS system, connected to the electrical service.

I love DIY and continue to safely take this path in many things. However I also always get a permit whenever required. These things are not mutually exclusive.

This protects me in that if there were a fire or someone got seriously hurt at least I would be able to say to anyone who asks that everything is on the up and up.

Unpermitted ESS is one of the main dangers we have been talking about in the codes and standards groups I am a part of like CALSSA and SEAC. If the rules become difficult for an average homeowner to install the ESS system they want per the codes, some portion of the population will try installation themselves with all the risks and rewards that entails.

The path I recommend is to apply for a permit for the electrical portion of this installation and interconnect with your utility as required. If you have hardware that eliminates export, simply show that to the utility during the interconnection process.

If your system was truly off grid, it would not be powered from the grid, and then interconnection would not be needed.

Practically, very small plug in PV systems "Balcony Solar" in the 600-800w range would probably be fine without interconnection in the future and I know some of the folks at Gizmo Solar are working on this with Florida Power and Light. Still there are code concerns such as overloading the circuit and GFCI hardware requirements not allowing bi-directional power flow generally.

 

[cali8484]

Practically, very small plug in PV systems "Balcony Solar" in the 600-800w range would probably be fine without interconnection in the future

This is has been done in Germany for a while now. No permit, no inspection, no interconnection agreement ... no problem. No need for US to wait. One reason why residential solar cost in Germany is half of US.

and I know some of the folks at Gizmo Solar are working on this with Florida Power and Light.

IIRC, those guys are dealing with much higher (>>800W) power systems.

Still there are code concerns such as overloading the circuit and GFCI hardware requirements not allowing bi-directional power flow generally.

Are you referring to the 800W plug-ins? If so then I don't see how 800W (<4A @ 240V, <8A @ 120V) would cause circuit overload.

 

[Vines]

Are you referring to the 800W plug-ins? If so then I don't see how 800W (<4A @ 240V, <8A @ 120V) would cause circuit overload.

The same way that busbars can be overloaded but with different circuit paths.

Say you plug in a heater to an outlet, which is on the same circuit as 6 other outlets and your "Balcony Solar" The heater draws 12A continuous, which is the limit of the 15A circuit. If someone else were to plug in another heater into this circuit the circuit breaker should trip before damage is done to the wiring.

However now assume that a plug in 120V Balcony Solar system is installed in between those 2 loads, generating another 8A. Now when the 2 heaters are plugged in, the wires see more amperage than they are designed for, and since the breaker is not supplying all the power to this system and additional power is getting injected in the middle of the run. The breaker might not trip and the circuit is now supplying 20A. Granted the safety factors mean this probably wont start a fire, but the code is intentionally conservative.

 

[jjrandorin]

Not sure if I can mention the products and other web forums by name... question to the Mod, please advise...

Im not quite sure I understand the question, but if the question is "can I say the name of another forum where I am discussing DIY PV / battery installs", then yes, you can say that here.

TMC has a rule against active re direction to other sites, but I would not consider "we are discussing these things more over at xxxx website" to be active re direction unless it was repeatedly mentioned in multiple threads or soemthing.

 

[cali8484]

The same way that busbars can be overloaded but with different circuit paths.

Say you plug in a heater to an outlet, which is on the same circuit as 6 other outlets and your "Balcony Solar" The heater draws 12A continuous, which is the limit of the 15A circuit. If someone else were to plug in another heater into this circuit the circuit breaker should trip before damage is done to the wiring.

However now assume that a plug in 120V Balcony Solar system is installed in between those 2 loads, generating another 8A. Now when the 2 heaters are plugged in, the wires see more amperage than they are designed for, and since the breaker is not supplying all the power to this system and additional power is getting injected in the middle of the run. The breaker might not trip and the circuit is now supplying 20A. Granted the safety factors mean this probably wont start a fire, but the code is intentionally conservative.

Sorry I don't see any part of the circuit carrying 20A. I can see 16A at most supplied from the 15A breaker and that should trip it at some point.

 

[Vines]

Sorry I don't see any part of the circuit carrying 20A. I can see 16A at most supplied from the 15A breaker and that should trip it at some point.

I agree that practically it won't likely be a problem.

If the 800W is injected between the breaker and the 2 loads then the load on the wiring will be slightly worse. The 2 loads together want 24A and the breaker will supply 16A, while the PV supplies the other 8A. Whether or not the breaker trips, there is an overload condition on the wire.

 

[cali8484]

If the 800W is injected between the breaker and the 2 loads then the load on the wiring will be slightly worse. The 2 loads together want 24A and the breaker will supply 16A, while the PV supplies the other 8A. Whether or not the breaker trips, there is an overload condition on the wire.

True but that's not really different with or without PV. Putting 2 heaters on the same circuit is the real problem. Similar to the risk of people putting extension cords on extension cords. A small PV makes little difference to such risks.

 

[Vines]

True but that's not really different with or without PV. Putting 2 heaters on the same circuit is the real problem. Similar to the risk of people putting extension cords on extension cords. A small PV makes little difference to such risks.

Totally true and the intended function is the breaker trips before the wire overloads. The difference being with the extra 800w injected into the circuit, the breaker might not trip, since it isn't significantly overloaded, only the wire is overloaded.

With just 2 heaters and no generation injected the breaker will trip (hopefully) and the homeowner will be alerted that they caused the issue.

With 2 heaters and the PV on the same circuit, they might not get the breaker to trip and the first sign of an issue might be smoke or a burned out outlet or wire.

 

[stagepuppy]

The path I recommend is to apply for a permit for the electrical portion of this installation and interconnect with your utility as required. If you have hardware that eliminates export, simply show that to the utility during the interconnection process.

Appreciate your advice on this. If it has to stay off grid, that's just one less feature among many plusses.

 

[GateFather]

I got an update from another project advisor who is not mine personally:

View attachment 988444

This actually makes somewhat good sense for once. What is interesting is that it sounds like ALL PW3's have a PV inverter inside vs. the PW+ has a PV inverter and the PW2 does not. I can't imagine I am the only one who has a utility with a PV array/inverter limit, so Tesla is going to be running into this issue everywhere across the country bc of their design choice with the PW3.

I still don't believe this actually matters but it at least makes somewhat of logical sense. What doesn't make sense is how my inverter would be 20 kW when my solar array is 9.315 kW with more than one PW3. That is a DC/AC ratio well under one? Weird.

I am dealing with the same thing right now. My system iis somewhat larger at 23.49 (58x 405 panels) with 34 southeast facing and 24 northwest facing. I ordered with 4x Powerwall 3s and the planset I got back had 2 Powerwall+ and 2 Powerwall 2s. When i asked about this, they told me that my utility here in NJ also limits total system AC output to 21kW. So the 7.6kW AC from the Powerwall Plus and an extra 5.7kW AC inverter gets me to 20.9kW which is their plan. You can see more of my detail here on this forum. This was the message my project advisor sent to me after I asked if they could move the ground level equipment (batteries, inverters) into my garage and if they could try to get me Powerwall 3s:

"I have a few updates to share. Our Design and Engineering Team thoroughly reviewed and confirmed the following. First, we cannot install the Powerwalls inside your garage. New Jersey does not allow attached garage installs for ESS (Powerwall) units in any capacity according to the current guidelines. Also, in your local area, we cannot reduce site export limits on the Powerwall 3. Your utility provider aggregates the full battery inverter capacity. We must design the system in a way where each Powerwall 3 has to be counted in full as 11.50 kW AC. Therefore, changing to Powerwall 3 would violate the AC limit and they will not accept alternatives like site export limits to bypass this requirement. Overall, we are still able to offer a whole home backup solution with the Powerwall 2s instead. Thank you."

He meant Powerwall Plus and Powerwall 2s as my planset shows this design:

If this is true - it is likely a restriction utilities have across the country, so it seems to me that PW3 are really meant for those who want 1, maybe at most 2. But it will be very rare to see setups with 3 or 4 PW3s.

 

[Vines]

I am dealing with the same thing right now. My system iis somewhat larger at 23.49 (58x 405 panels) with 34 southeast facing and 24 northwest facing. I ordered with 4x Powerwall 3s and the planset I got back had 2 Powerwall+ and 2 Powerwall 2s. When i asked about this, they told me that my utility here in NJ also limits total system AC output to 21kW. So the 7.6kW AC from the Powerwall Plus and an extra 5.7kW AC inverter gets me to 20.9kW which is their plan. You can see more of my detail here on this forum. This was the message my project advisor sent to me after I asked if they could move the ground level equipment (batteries, inverters) into my garage and if they could try to get me Powerwall 3s:

"I have a few updates to share. Our Design and Engineering Team thoroughly reviewed and confirmed the following. First, we cannot install the Powerwalls inside your garage. New Jersey does not allow attached garage installs for ESS (Powerwall) units in any capacity according to the current guidelines. Also, in your local area, we cannot reduce site export limits on the Powerwall 3. Your utility provider aggregates the full battery inverter capacity. We must design the system in a way where each Powerwall 3 has to be counted in full as 11.50 kW AC. Therefore, changing to Powerwall 3 would violate the AC limit and they will not accept alternatives like site export limits to bypass this requirement. Overall, we are still able to offer a whole home backup solution with the Powerwall 2s instead. Thank you."

He meant Powerwall Plus and Powerwall 2s as my planset shows this design:

View attachment 1037360

View attachment 1037361

If this is true - it is likely a restriction utilities have across the country, so it seems to me that PW3 are really meant for those who want 1, maybe at most 2. But it will be very rare to see setups with 3 or 4 PW3s.

Or utilities accept that the Inverter is an electronic device, that can limit it's own output. The reason they do so is likely primarily that they dont have to, and making it more difficult to get PV+ESS means they keep more customers reliant on them.

Utilities are basically monopolies in many jurisdictions, so there is nobody else telling them what to do really. When there is oversight it is usually in name only.

 

[GateFather]

Or utilities accept that the Inverter is an electronic device, that can limit it's own output. The reason they do so is likely primarily that they dont have to, and making it more difficult to get PV+ESS means they keep more customers reliant on them.

Utilities are basically monopolies in many jurisdictions, so there is nobody else telling them what to do really. When there is oversight it is usually in name only.

In my opinion - it is this exactly. The technology is capable of limiting total output via hardware and/or software and there is no risk to their lineworkers if a Powerwall is sitting there with disabled inverters. They simply don't want people installing more panels, for example, after the fact and losing reliance on them. I have no choice on who to get my power generation from. Supply i can change, but not generation. Only through solar hence my move to solar.

 

[Jeremy3292]

I am dealing with the same thing right now. My system iis somewhat larger at 23.49 (58x 405 panels) with 34 southeast facing and 24 northwest facing. I ordered with 4x Powerwall 3s and the planset I got back had 2 Powerwall+ and 2 Powerwall 2s. When i asked about this, they told me that my utility here in NJ also limits total system AC output to 21kW. So the 7.6kW AC from the Powerwall Plus and an extra 5.7kW AC inverter gets me to 20.9kW which is their plan. You can see more of my detail here on this forum. This was the message my project advisor sent to me after I asked if they could move the ground level equipment (batteries, inverters) into my garage and if they could try to get me Powerwall 3s:

"I have a few updates to share. Our Design and Engineering Team thoroughly reviewed and confirmed the following. First, we cannot install the Powerwalls inside your garage. New Jersey does not allow attached garage installs for ESS (Powerwall) units in any capacity according to the current guidelines. Also, in your local area, we cannot reduce site export limits on the Powerwall 3. Your utility provider aggregates the full battery inverter capacity. We must design the system in a way where each Powerwall 3 has to be counted in full as 11.50 kW AC. Therefore, changing to Powerwall 3 would violate the AC limit and they will not accept alternatives like site export limits to bypass this requirement. Overall, we are still able to offer a whole home backup solution with the Powerwall 2s instead. Thank you."

He meant Powerwall Plus and Powerwall 2s as my planset shows this design:

View attachment 1037360

View attachment 1037361

If this is true - it is likely a restriction utilities have across the country, so it seems to me that PW3 are really meant for those who want 1, maybe at most 2. But it will be very rare to see setups with 3 or 4 PW3s.

OP here.

Despite the fact that Drew Baglino responded to me on X (Twitter) directly about this, don’t fight it as you’ll get nowhere. Just accept the PW+/2 combo or cancel your order. Take it from me who already went down that path and wasted a bunch of time.

They are supposed to have “dummy” PW3’s with no inverters in them but they just don’t seem to have them available yet or their teams are too stupid to know any better.

 

[GateFather]

OP here.

Despite the fact that Drew Baglino responded to me on X (Twitter) directly about this, don’t fight it as you’ll get nowhere. Just accept the PW+/2 combo or cancel your order. Take it from me who already went down that path and wasted a bunch of time.

They are supposed to have “dummy” PW3’s with no inverters in them but they just don’t seem to have them available yet or their teams are too stupid to know any better.

Really appreciate you responding. This is exactly what I was wondering. How worth it is it to fight/pursue. It seems the real "bad guy" here is the utility who likely has these caps only to ensure some level of dependency on the grid remains and people cannot truly be self sustaining with solar. It sucks! Can you link the tweet you're referencing by the way?

What did you wind up doing? I am thinking I will take the 2 PW+ and 2 PW 2 setup, but I am asking if they will discount since it is technically older hardware for the same price as what would be Powerwall 3s with better specs if utility did not limit it.

 

[Jeremy3292]

Really appreciate you responding. This is exactly what I was wondering. How worth it is it to fight/pursue. It seems the real "bad guy" here is the utility who likely has these caps only to ensure some level of dependency on the grid remains and people cannot truly be self sustaining with solar. It sucks! Can you link the tweet you're referencing by the way?

What did you wind up doing? I am thinking I will take the 2 PW+ and 2 PW 2 setup, but I am asking if they will discount since it is technically older hardware for the same price as what would be Powerwall 3s with better specs if utility did not limit it.

Check my signature for all the details. I’m finally now just waiting on install but they are backed up 3 months so I’m not until mid July at this point. Probably another month or so more for utility approval after that so it’ll be a year since ordering once it’s all done done it looks like.

They won’t lower the price, don’t bother asking as they are already the cheapest out there. If you read threads on here about Tesla Solar they are certainly the cheapest pricing, which is why I went with them, but you’re not going to get a lot of traction getting things “custom” done or this or that. You’ll have to be your own project advisor and bug them to keep things moving. I spent 4 months just waiting on the freaking permit, only to realize they were dragging their feet on it wasting time and then I hammered them weekly to provide me an update and get it done.

I don’t have any regrets about it as I’m saving literally thousands and thousands of dollars versus my local reputable installer but just be aware is all.

PW2/+ is a fine product and I decided one in the hand is worth more than two in the bush as they say.

https://twitter.com/x/status/1758497227205726270

 

[GateFather]

Check my signature for all the details. I’m finally now just waiting on install but they are backed up 3 months so I’m not until mid July at this point. Probably another month or so more for utility approval after that so it’ll be a year since ordering once it’s all done done it looks like.

They won’t lower the price, don’t bother along. If you read threads on here about Tesla Solar they are certainly the cheapest pricing, which is why I went with them, but you’re not going to get a lot of traction getting things “custom” done or this or that. You’ll have to be your own project advisor and bug them to keep things moving. I spent 4 months just waiting on the freaking permit, only to realize they were dragging their feet on it wasting time and then I hammered them weekly to provide me an update and get it done.

I don’t have any regrets about it as I’m saving literally thousands and thousands of dollars versus my local reputable installer but just be aware is all.

PW2/+ is a fine product and I decided one in the hand is worth more than two in the bush as they say.

https://twitter.com/x/status/1758497227205726270

Yeah I got one other quote and it was $14k more for the same system. So I will stick with Tesla. Although I'd really like to get the new PW3s, I mostly see now they are really meant for people getting 1 or maybe 2 PWs in some cases but will rarely work for those who want 3+ PWs for more backup or to run a home with more energy usage and/or with EV(s). Either Tesla will come out with a PW3 expansion unit without inverters, or they will continue to sell PW2 and PW+ for situations like ours, I guess. I'm still interested to hear what Drew Baglino said to you on X

 

[MP3Mike]

Either Tesla will come out with a PW3 expansion unit without inverters

It is in their roadmap for Q3:

Though that said Q1 was the last time to buy PW2/+, but maybe they had to backoff on that because of the utility rules like you are running into.