PGE Interconnect: How to Limit Export?

[saenns]

I'm planning a DIY grid-tie roof-top solar power system with battery backup. I'm trying to apply for interconnection ASAP so I can secure NEM 2.0 before the deadline. I'm exploring the PGE interconnection application form and I cannot answer the following question:

"How do you plan to limit export?"

Options:
* Power Control System (Option 10)
* Relay (Option 1)
* Derated Inverter

Screenshot attached.

Do I even want to limit export? I figured that would be true when the batteries are charging or if I were time-shifting.

 

[timselectric]

You have to limit export for two reasons.
1) you have to limit the maximum amount to your NEM agreement.
2) you have to limit your export to zero when the grid is down.

 

[400bird]

I checked the "no" box for limiting export. I didn't feel like explaining to them how I was going to limit export.

When the grid is down is another question on the forms. I don't think this export question is related to that.

 

[740GLE]

You have to limit export for two reasons.
1) you have to limit the maximum amount to your NEM agreement.
2) you have to limit your export to zero when the grid is down.

What about when the grid doesn’t need solar?

I think that’s the biggest issue facing Cali Grid operators today.

 

[timselectric]

What about when the grid doesn’t need solar?

I think that’s the biggest issue facing Cali Grid operators today.

Yeah, it's too much hassle to even deal with the grid anymore. Which is why it's not even a remote thought for me.

 

[saenns]

Thanks everyone. I like the idea of just now answering the question. But if I were to answer, and I were using a Solark 15K, then what would I select for "How to limit export?". Relay is obviously not the one. But between "power control system" vs "derated inverter" I don't know. I tried reading the handbook.

 

[saenns]

Well CEC lists the Sol-Ark as "Inverter with PCS functionality". So I suppose the answer would be Power Control System.

I am tempted to save $ and use a MPP Solar LVX6048WP instead of the Sol-Ark 15k. But it's not in the list of approved inverters despite being UL 1741 SA since March 2022. Is that because it's relatively new or because it doesn't qualify?

 

[timselectric]

Well CEC lists the Sol-Ark as "Inverter with PCS functionality". So I suppose the answer would be Power Control System.

I am tempted to save $ and use a MPP Solar LVX6048WP instead of the Sol-Ark 15k. But it's not in the list of approved inverters despite being UL 1741 SA since March 2022. Is that because it's relatively new or because it doesn't qualify?

It's because it's not a grid-tied inverter. So, it doesn't need to be on the power companies list. (It doesn't export to the grid)
AFAIK

 

[saenns]

You're right about the LVX6048 but not the LVX6048WP which supports grid export

New All in One: MPP LVX6048WP (UL certified)

I discovered this coming soon model. It looks pretty great. Split phase, UL certified, 2 PV inputs, water proof. What I can not tell is the bypass limits to run the load off of utility, if solar is limited and battery depleted. Is it the 30A spec? If so, that seems low. Is it? Or can...

diysolarforum.com

Can I change my inverter next year after getting Permission to Operate from PGE and remain grandfathered under NEM 2.0?

 

[timselectric]

You're right about the LVX6048 but not the LVX6048WP which supports grid export

Ah, ok.

Can I change my inverter next year after getting Permission to Operate from PGE and remain grandfathered under NEM 2.0?

Someone else will have to answer this.
I have never been grid-tied or had a NEM agreement.

 

[Hedges]

What about when the grid doesn’t need solar?

I think that’s the biggest issue facing Cali Grid operators today.

That would be "Rule 21" aka "UL-1741-SA", a method to tell GT PV inverters to reduce power output in response to increasing frequency and voltage.
There is also a function to tell them over the internet.

AC coupled systems with battery inverter and GT PV inverter use frequency shift.

You're right about the LVX6048 but not the LVX6048WP which supports grid export

New All in One: MPP LVX6048WP (UL certified)

I discovered this coming soon model. It looks pretty great. Split phase, UL certified, 2 PV inputs, water proof. What I can not tell is the bypass limits to run the load off of utility, if solar is limited and battery depleted. Is it the 30A spec? If so, that seems low. Is it? Or can...

diysolarforum.com

Can I change my inverter next year after getting Permission to Operate from PGE and remain grandfathered under NEM 2.0?

Are you already under NEM 2.0? Wouldn't that mean already have permission to operate?

Or are you planning to get your first system accepted by PG&E before about April of 2023 so you'll be under NEM 2.0, then change inverter later?

Once you have an approved system, you can make replacements with other equipment meeting the requirements back when it was approved.

 

[saenns]

Or are you planning to get your first system accepted by PG&E before about April of 2023 so you'll be under NEM 2.0, then change inverter later?

Yes that's right.

Once you have an approved system, you can make replacements with other equipment meeting the requirements back when it was approved.

Excellent, thank you

 

[Hedges]

I think my city does not require a permit to replace electrical equipment. But for things like water heaters they do.
Don't know if PG&E expects to be informed when an inverter or solar panel is replaced.
In practice, if a compliant inverter is installed, it will still perform according to UL-1741-SA, and what PG&E doesn't know won't hurt them.

Of course, whatever grid interactive inverter you install with permit and get permission to operate has to be on a list of approved equipment.
Something that doesn't export (a UPS) would not, but then you wouldn't be on NEM x.x

Similar thoughts are crossing my mind. I'm considering a new system for another property, and I have a quantity of inverters compliant only to the old rules. Also a couple compliant to the new, but they are 3-phase and that property is not.

 

[400bird]

When I was filling this out recently, I checked "no" and the drop down disappeared. Why do you need to limit export? The system let my application through with "no" checked. I don't have a Sol-Ark, but it seemed to work.

When it says limit export, the question is vague. I don't think it's talking about rule 21, as that is a requirement of an approved inverter. I'd say they are more likely talking about peak export. That makes the most sense as a derated inverter would limit peak export.