NEM PGE Application Questions

[Kuma]

Applying for PGE NEM for a new residential solar system. I would like to make the system about 2.5kw larger than current annual usage. When I get to the "Usage and Production" area it displays "Estimated Solar Annual Production and "Your Recent Annual Usage (kWh)". The delta is 2.3 kw. The following message/warning is displayed:

"NEM Systems should be sized with an estimated annual production no larger than 100% of the customers total previous 12 months usage(annual usage) and projected future increase if applicable.

Your proposed facility does not meet the guideline that it should be sized so that your estimated annual generation is no larger than 100% of your previous annual usage plus any planned increase."


In the "Planned Increase In Annual Usage (kWh)" area, just above the warning message, I put 2.3kw. But, their is no area to explain why the increased production is warranted and the above warning message remains.

Is this going to cause the submission to get rejected? Any ideas or work arounds?

In the next section their is this:

"Will an electric vehicle recharging facility be included as part of the load at this location?" I dont plan on an EV or installing a charging cable but if its necessary to address the above issues so be it. This is in another section of the form and does not seem to be related to increased solar production. But, it could be.


Also, under "New Equipment, "Please provide the method of Transition". The choices are "closed or "open". The inverter will be a SMA Sunny Boy String Inverter. Is it closed or open transition?


Its Saturday night and I can not contact SMA and Im trying to submit the application this weekend to allow time for review(s) and possible rejection(s).


Thank you!

 

[400bird]

In the "Planned Increase In Annual Usage (kWh)" area, just above the warning message, I put 2.3kw. But, their is no area to explain why the increased production is warranted and the above warning message remains.

Is this going to cause the submission to get rejected? Any ideas or work arounds?

I've done NEM applications twice for my house. Once in 2018 and the second time on 2020.
Both times I ran into this. In 2018, I entered some random number (in kWh) to get me over the threshold. I think I was at 105% production vs historical use, so the increase wasn't huge.
In 2022, I looked up a heat pump water heater and entered that number for my planned/estimated increased usage. I think the delta here was something like 50kWh for the year, so I wasn't far over the estimated production vs. historical usage number.

Neither time did it come up ever again. Not a single question. Your entry of 2.3kW doesn't make sense to me, as when I filled out the forms it was annual kWh, I'd expect the delta to normally be in the 1000's of kWh. Not 2.3kW

In the next section their is this:

"Will an electric vehicle recharging facility be included as part of the load at this location?" I dont plan on an EV or installing a charging cable but if its necessary to address the above issues so be it. This is in another section of the form and does not seem to be related to increased solar production. But, it could be.

I think this is unrelated to getting the NEM approval, likely about getting you on the EV plan or some other metric.

Also, under "New Equipment, "Please provide the method of Transition". The choices are "closed or "open". The inverter will be a SMA Sunny Boy String Inverter. Is it closed or open transition?

Can you post a screenshot of that question? I feel like the wording of the question is slightly different compared to what I'm reading here now.

 

[Kuma]

I've done NEM applications twice for my house. Once in 2018 and the second time on 2020.
Both times I ran into this. In 2018, I entered some random number (in kWh) to get me over the threshold. I think I was at 105% production vs historical use, so the increase wasn't huge.
In 2022, I looked up a heat pump water heater and entered that number for my planned/estimated increased usage. I think the delta here was something like 50kWh for the year, so I wasn't far over the estimated production vs. historical usage number.

Neither time did it come up ever again. Not a single question. Your entry of 2.3kW doesn't make sense to me, as when I filled out the forms it was annual kWh, I'd expect the delta to normally be in the 1000's of kWh. Not 2.3kW

I think this is unrelated to getting the NEM approval, likely about getting you on the EV plan or some other metric.

Can you post a screenshot of that question? I feel like the wording of the question is slightly different compared to what I'm reading here now.

I went back and reviewed everything and the "Usage and Production" displays this message. I think Im ok now? I increased number of panels and entered 3500. I also entered 2500 and the same message was displayed. You were right, 2.5kw caused the problem, user error.

Also, PGE using last years usage is unrealistic as we were out of the country last year for a several months.

I found a good price on panels but prefer not to buy anything until PGE approves the submission. However, given the price of the panels and that they are local, no shipping costs, Im afraid they may not be available for long. Do you think PGE will approve the submission with the 3500kw increase from last years usage and that its safe to buy the quantity of panels needed for the increase?






Transition Open or Closed




Is this the correct SLD? I have seen some SLD that are more detailed but this seems correct.

 

[400bird]

You might get some pushback on the planned increased usage. You are looking to put up double the 2022 usage. What was your 2021 number? That might be enough backup if they question it. Or do you have any real planned increased usage?

Now that I see the method of transfer question, I remember the pop up explanations on the right.
It is probably open, most are.

What's your inverter model?

You checked the "going to be used as a backup" that requires a battery inverter with integrated transfer switch/relays.
I am not a SMA expert, but I don't think SMA offers an all in one that can provide battery back up, Solar input, and the integrated transfer relays.
The correct answer the the backup question is likely no.

I will summon @Hedges as he's the resident SMA master.

 

[MisterSandals]

I will summon @Hedges as he's the resident SMA master.

You'll have to ping him with a message, for some reason he does not get notification from incantation of his name.

 

[Kuma]

You might get some pushback on the planned increased usage. You are looking to put up double the 2022 usage. What was your 2021 number? That might be enough backup if they question it. Or do you have any real planned increased usage?

Now that I see the method of transfer question, I remember the pop up explanations on the right.
It is probably open, most are.

What's your inverter model?

You checked the "going to be used as a backup" that requires a battery inverter with integrated transfer switch/relays.
I am not a SMA expert, but I don't think SMA offers an all in one that can provide battery back up, Solar input, and the integrated transfer relays.
The correct answer the the backup question is likely no.

I will summon @Hedges as he's the resident SMA master.

Yes, SMA Sunny Boy needs another module (Sunny Island) for battery backup and its expensive. Changed backup to "No".

Inverter model depends on what system size gets approved or I decide. Looking at Sunny Boy 3.8kw or 5.0kw and may oversize a bit. Can oversize SMA ~133%.

I cant decide system size to be honest. I want to over size because of current 30% tax credit, self installation, and I'm getting older - may not be motivated and/or possible to increase production 5~10 years from now . Other considerations: EV in the future, replace 25+ year old propane clothes dryer to electric, replace 20+ year old propane furnace to electric heat pump.

The prior years usage is about the same since we were also out of the country for three months.

Trying to decide between 10 and 12 panels. This is 6800kw (12 panels) with the CEC rating of 4780kw. Actual usage about 3400kw

10 Panels CEC is 3984 kw. The CEC realistic production values are a lot closer to actual usage than STC.

 

[Hedges]

Right. It shows up under the bell icon, which I sometimes look through for thumbs up, etc. but also has every reply. Mostly, I open replies that come to my email inbox. Invocations by name aren't emailed.

I don't know for sure on the PG&E approvals of recent times because mine is still going back and forth.

I don't anticipate any problems with increased consumption, which I have indicated and they haven't objected to. People are asked to replace gas heating with electric, and to use EV. No reasons are even requested by PG&E.

When you do a service upgrade they do ask about types of loads, and for EV it says not to list that unless you already have one. But for NEM 2.0 agreement, you just list the anticipated kWh/year increase.

I would agree that avoiding battery backup and transfer switch on NEM 2.0 agreement is better; you are allowed to add battery in the future and remain under NEM 2.0, so if using separate GT PV inverter best to just list that and leave battery inverter out of the picture. If Hybrid then I guess you gotta address it now.

I mentioned Sunny Island on my initial application, for conversion between split-phase grid and 3-phase "TriPower" GT PV inverter. They questioned the mismatch, then rejected my model TriPower for lack of grid support features, didn't mention the Sunny Island. I've since said it will be Sunny Boy -41 model and haven't heard back.

Another guy said PG&E rejected Sunny Island. Of course it is not UL-1741-SA. Should be acceptable as a UPS, but likely to cloud the issue for now.

Reserving with a Sunny Boy for now, you may be able to switch to the SMA Hybrid when it arrives this summer. That will not support AC coupling. Will be high-voltage battery (like Sunny Boy Storage). Has internal transfer switch (unlike SBS)

If you want Sunny Island, you can get them new in the box around $2500 each. Two of those is no more than SBS + ABU. More powerful, but lacks the time shift and export limit features.

Go as much oversize as you can get away with or fit on the roof.
If DIY, hardware costs $1.25/W, makes power for $0.03/kWh. Turnkey installed, 2x to 4x that price. Still much cheaper than PG&E so better to install more than you need rather than buying some power for $0.25 to $0.50

"Can oversize SMA ~133%" ?
You can overpanel the hell out of it. Voc and Imp of panels may allow more or less; larger panels single string might fill an MPPT, while panels in the 300W range could allow two parallel strings per MPPT and overpaneling to 200%

Determine what wattage inverter can backfeed your utility panel within 120% rule and max that out. Unless you go for a utility panel replacement.

If you later install Sunny Island, it is convenient to have 70A PV breaker, allows maximum 56A pass-through continuously. That fits a 225A busbar (x 120% = 270A) with 200A main breaker. Not that I would be concerned about putting in a 70A breaker if 120% rule only allows 40A, if PV wattage is smaller. But nice to obey code when possible.

 

[Kuma]

Right. It shows up under the bell icon, which I sometimes look through for thumbs up, etc. but also has every reply. Mostly, I open replies that come to my email inbox. Invocations by name aren't emailed.

I don't know for sure on the PG&E approvals of recent times because mine is still going back and forth.

I don't anticipate any problems with increased consumption, which I have indicated and they haven't objected to. People are asked to replace gas heating with electric, and to use EV. No reasons are even requested by PG&E.

When you do a service upgrade they do ask about types of loads, and for EV it says not to list that unless you already have one. But for NEM 2.0 agreement, you just list the anticipated kWh/year increase.

I would agree that avoiding battery backup and transfer switch on NEM 2.0 agreement is better; you are allowed to add battery in the future and remain under NEM 2.0, so if using separate GT PV inverter best to just list that and leave battery inverter out of the picture. If Hybrid then I guess you gotta address it now.

I mentioned Sunny Island on my initial application, for conversion between split-phase grid and 3-phase "TriPower" GT PV inverter. They questioned the mismatch, then rejected my model TriPower for lack of grid support features, didn't mention the Sunny Island. I've since said it will be Sunny Boy -41 model and haven't heard back.

Another guy said PG&E rejected Sunny Island. Of course it is not UL-1741-SA. Should be acceptable as a UPS, but likely to cloud the issue for now.

Reserving with a Sunny Boy for now, you may be able to switch to the SMA Hybrid when it arrives this summer. That will not support AC coupling. Will be high-voltage battery (like Sunny Boy Storage). Has internal transfer switch (unlike SBS)

One SMA reseller mentioned SMA has new models coming. Is it worth waiting for the new models? Are you saying get the application approved and months later ask for a change? As a noob and comparing inverters, SMA seems lacking features. Growatts seems more robust but for various reasons SMA seems the safer choice "for me".

Their is a Solaredge 5kw inverter for only $600. Price is good but not sure if it will pass PGE/permits/inspections without optimizers. Solaredge claims it needs optimizers. I'm not totally convinced after watching various videos. The roof has no shading issues and one roof faces west, the east. 2 MPPT inputs would work just fine.


PGE Rules for Changing Equipment:

A one-time modification request will be allowed for:
• Like-for-like equipment replacements (this may work if waiting for new SNMA models makes sense)
• System size reductions not exceeding 20% (Any upgrades or mitigations caused by the change would be paid for by the customer.)
• System size reductions to avoid upgrades if the re-study determines the modification affects no other distributed energy resource (This modification requires a $300 fee.)

If you want Sunny Island, you can get them new in the box around $2500 each. Two of those is no more than SBS + ABU. More powerful, but lacks the time shift and export limit features.

Go as much oversize as you can get away with or fit on the roof.
If DIY, hardware costs $1.25/W, makes power for $0.03/kWh. Turnkey installed, 2x to 4x that price. Still much cheaper than PG&E so better to install more than you need rather than buying some power for $0.25 to $0.50

"Can oversize SMA ~133%" ?
You can overpanel the hell out of it. Voc and Imp of panels may allow more or less; larger panels single string might fill an MPPT, while panels in the 300W range could allow two parallel strings per MPPT and overpaneling to 200%

I emailed PGE asking what size system is allowed for new installs with respect to "Annual Usage" history. Given your comments about maximizing the roof area, I probably said too much mentioning the preferred 6.9kw size. 12 430 w panels, 6.9kw production STC. More panels could be installed on the opposing roof facing 80* almost east, but not ideal exposure though.

The SP is 200 amps, 40 amp PV breaker allowed. I want to feed inverter into a 60amp subpanel but "I think" the 120% rule still applies. 60 amp sub panel = 12 amp PV breaker.

Many complications to go from the barn/shop roof with PV's to the house side where 200 amp service panel is located. I think the 60amp subpanel will have to become an AC disconnect so the 120% 40amp rule remains.

Barn/PV -> 130ft -> ac disconnect replacing 60amp SP |HOUSE| ac disconnect -> 200amp SP

Determine what wattage inverter can backfeed your utility panel within 120% rule and max that out. Unless you go for a utility panel replacement.

Replaced Service Panel 5 years ago to 200 amp. Was not thinking solar back then.

If you later install Sunny Island, it is convenient to have 70A PV breaker, allows maximum 56A pass-through continuously. That fits a 225A busbar (x 120% = 270A) with 200A main breaker. Not that I would be concerned about putting in a 70A breaker if 120% rule only allows 40A, if PV wattage is smaller. But nice to obey code when possible.

 

[400bird]

That last post exposed that you probably have lots of reading to do.

Search NEM 2.0, successor teriff, and NEM 3.0
The deadline for (the significantly more favorable) NEM 2.0 is coming very quickly.

No matter what inverter you choose, when roof mounted, you are required to put electronics on the panel. Rapid shut down requires panel level disconnects.
Solar Edge does this with the optimizers, so they are required for that reason also, not just the software/operational stuff you were referring to.
With the SMA inverter you will need to add an RSD module to each panel. Something like a Tigo or AP systems brand RSD.
Micro inverters do this integrated into the inverters under each panel.

Are you installing this system yourself?

 

[Hedges]

One SMA reseller mentioned SMA has new models coming. Is it worth waiting for the new models? Are you saying get the application approved and months later ask for a change?

You do need to get it approved before NEM 2.0 deadline.
If you like other equipment that later become available you can consider the change.

As a noob and comparing inverters, SMA seems lacking features. Growatts seems more robust but for various reasons SMA seems the safer choice "for me".

Any Growatts on the CEC list?
GroWatt may be more feature rich. SMA will be more robust. Fronius likely comparable.

Their is a Solaredge 5kw inverter for only $600. Price is good but not sure if it will pass PGE/permits/inspections without optimizers. Solaredge claims it needs optimizers. I'm not totally convinced after watching various videos. The roof has no shading issues and one roof faces west, the east. 2 MPPT inputs would work just fine.

Is that inverter on CEC list? Not just UL-1741-SA but also has "Y" in other columns (not seen on CEC web page, but in the Excel spreadsheet you can download)?
PG&E rejected my -SA inverter for lacking those other features.

With what I've seen indicating higher failure rate I would not select solar edge.

PGE Rules for Changing Equipment:

I didn't know about those. Funny the restrict reductions (even if they didn't invest money to support your planned larger system.)

Replaced Service Panel 5 years ago to 200 amp. Was not thinking solar back then.

Double-check if really 200A. Some are 225A.
For 40A PV breaker, good enough either way.
If you want to use a battery inverter later, address it then.

 

[Kuma]

That last post exposed that you probably have lots of reading to do.

Search NEM 2.0, successor teriff, and NEM 3.0
The deadline for (the significantly more favorable) NEM 2.0 is coming very quickly.

No matter what inverter you choose, when roof mounted, you are required to put electronics on the panel. Rapid shut down requires panel level disconnects.
Solar Edge does this with the optimizers, so they are required for that reason also, not just the software/operational stuff you were referring to.
With the SMA inverter you will need to add an RSD module to each panel. Something like a Tigo or AP systems brand RSD.
Micro inverters do this integrated into the inverters under each panel.

Are you installing this system yourself?

Yes, several weeks left providing an opportunity to learn more. I spoke with a few resellers, some are well known, and none mentioned the electronics roof top requirement.

Anyway, Enphase is lacking in large panel support. IQ8H is their best option with new models for larger panels coming in a couple months. I could do an application change after approval when the new Enphase are available. APsystems requires certified installers. I do like APsystems dual inverters though.

Also, "in this noobs opinion" electronics on the roof is undesirable for many reasons. But if the govt says its necessary, then thats the direction. Thank you!

Do you have any knowledge of sizing the system per NEM 2 for new installs?


And yes, I look forward to installing the PV system myself.

 

[zanydroid]

I found a good price on panels but prefer not to buy anything until PGE approves the submission. However, given the price of the panels and that they are local, no shipping costs, Im afraid they may not be available for long. Do you think PGE will approve the submission with the 3500kw increase from last years usage and that its safe to buy the quantity of panels needed for the increase?

Installers have told me that PG&E doesn't really check that hard under NEM2 and you can also submit an oversizing attestation as needed.

Renvu (local to Bay Area) will hold panels for you if you pay in advance. They told me they will refund 100% if there needs to be a change.

Given the impending deadline I HIGHLY recommend getting someone to do your plans. You have less than 4 weeks left and are still going back and forth with manufacturers, along with basics on code and NEM process. You really need to reduce the number of things you are juggling unless you plan on working full time learning for this project... and even if you do that there is considerable risk from mis-learning.

• Lock a reasonable price inverter and treat that as a sunk cost for your education in solar.
• Figure out how to hire someone tomorrow instead of spending time trying to reach a manufacturer to answer your technical questions
• Flip a coin between inverter and microinverter, lock that decision, and go with it. This is not a good time to re-legislate decisions like that
• Forget about storage, this is even more complicated than just getting grid tie right the first time

 

[zanydroid]

Learning is good and all, but only if you have sufficient control over the process and timelines.

In terms of timing. PG&E seems to have slowed down reviews, there are some people on the forum that have been waiting for two weeks. It's not clear what would happen if they return your application for correction of deficiency on April 8...

 

[zanydroid]

APsystems requires certified installers. I do like APsystems dual inverters though.

Hoymiles does not require certified installers and they have 2- and 4-port inverters.

However, there is a question for me as to whether HM- or newer HMS- series inverters will be approved by PG&E given the impending April 1 deadline to require 1741SB (or equivalent). Only HMS series clearly state 1741SB listing. I'm possibly rolling the dice by having submitted an HM- inverter application 1.5 weeks ago.

If I was submitting an application end of March I probably would pay the 20% premium for HMS- series to derisk this instead of risking going on NEM3

 

[Kuma]

Installers have told me that PG&E doesn't really check that hard under NEM2 and you can also submit an oversizing attestation as needed.

Renvu (local to Bay Area) will hold panels for you if you pay in advance. They told me they will refund 100% if there needs to be a change.

Given the impending deadline I HIGHLY recommend getting someone to do your plans. You have less than 4 weeks left and are still going back and forth with manufacturers, along with basics on code and NEM process. You really need to reduce the number of things you are juggling unless you plan on working full time learning for this project... and even if you do that there is considerable risk from mis-learning.

• Lock a reasonable price inverter and treat that as a sunk cost for your education in solar.
• Figure out how to hire someone tomorrow instead of spending time trying to reach a manufacturer to answer your technical questions
• Flip a coin between inverter and microinverter, lock that decision, and go with it. This is not a good time to re-legislate decisions like that
• Forget about storage, this is even more complicated than just getting grid tie right the first time

Good advice. Regarding plans, after NEM approval their is a 3 year time period for installation. In other words, system does not have to be installed until April 2026. I just need to get approval before April 14


"To retain eligibility, final electrical clearance (often referred to as final building or electrical permit) must be submitted before April 15, 2026"


Before 11:59 p.m. on April 14, 2023, you must submit the following:
• Completed application, free of major deficiencies (e.g. no blanks, incomplete/inaccurate document, changes requiring resubmission per Rule 21)
• A single-line diagram (a simplified representation of an electrical system)
• A signed Contractor State License Board (CSLB) Disclosure and Solar Consumer Protection Guide (for residential, non-self install only)
• A signed Agreement and Authorization Form (for Standard NEM only

 

[zanydroid]

I just need to get approval before April 14

Sure but frankly you may not converge to an approved application by April 14 with your current approach.

Another thing to keep in mind is that your city may expire an approved permit after a period of time. Mine does, after 12 months. So I would have to pay $700+ again. Well maybe less because the express electronic review should be implemented next year, but still a waste of money.

 

[Hedges]

Given the impending deadline I HIGHLY recommend getting someone to do your plans.

Do you know if formal plans, and city permit issued, are required by PG&E?

NEM 2.0 deadline is April 14th.
But I've read that UL-1741 supplement "B" is adopted by California as of April 1st. Makes me wonder if the "A" but not "B" inverters on CEC's list will be disallowed as of that date. Better early than sorry?

You have less than 4 weeks left and are still going back and forth with manufacturers, along with basics on code and NEM process. You really need to reduce the number of things you are juggling unless you plan on working full time learning for this project... and even if you do that there is considerable risk from mis-learning.

• Lock a reasonable price inverter and treat that as a sunk cost for your education in solar.
• Figure out how to hire someone tomorrow instead of spending time trying to reach a manufacturer to answer your technical questions

• Flip a coin between inverter and microinverter, lock that decision, and go with it. This is not a good time to re-legislate decisions like that
• Forget about storage, this is even more complicated than just getting grid tie right the first time

I think Enphase microinverters are known to work reliably with Enphase battery system (expensive), and I've read mixed results using them with other battery inverters.

I think string inverters (having Rule-21 as required for new installs) will work well with low-frequency battery inverters that support AC coupling. There are high-frequency inverters too, but people say it is more difficult for those to do AC coupling.

I have experience with older model (but not newer models currently on CEC list) SMA inverters, and using them with low-frequency SMA battery inverter. What I've used is not Rule-21; older models have "backup" and "offgrid" modes which I know work well. I'm going with SMA Sunny Boy -41 series for NEM 2.0 reservation(s). If their Rule-21 setting works less than ideally, I know they have an "offgrid" mode which will be good.

Before 11:59 p.m. on April 14, 2023, you must submit the following:
• Completed application, free of major deficiencies (e.g. no blanks, incomplete/inaccurate document, changes requiring resubmission per Rule 21)
• A single-line diagram (a simplified representation of an electrical system)
• A signed Contractor State License Board (CSLB) Disclosure and Solar Consumer Protection Guide (for residential, non-self install only)
• A signed Agreement and Authorization Form (for Standard NEM only

I hope that's all. Drawings hold me up. (when they're not CAD I have and am familiar with, such as OrCAD at work.)

 

[Kuma]

Sure but frankly you may not converge to an approved application by April 14 with your current approach.

Another thing to keep in mind is that your city may expire an approved permit after a period of time. Mine does, after 12 months. So I would have to pay $700+ again. Well maybe less because the express electronic review should be implemented next year, but still a waste of money.

One recent limiting factor was that retailers and suppliers were closed yesterday and today. I spoke with a helpful, knowledgeable, Enphase employee last week. He will get called back tomorrow to further discuss the new micro inverters and making changes to the nem application after approval. I already researched micro inverters and have some level of understanding. The panel supplier will also get called in the morning.

I also emailed PGE yesterday asking a few questions to prevent, at least reduce, rejection(s). They took two days last time to reply. Received the reply yesterday, Saturday. Asking questions via email seems like a faster approach then submitting an application, waiting several days for possible rejection, resubmitting, waiting several days again... Time will tell of course

No permits will be pulled until I have the equipment here or ordered so not worried about that process. Have pulled permits many times with building 24x36 ft barn/shop, electrical, plumbing, service panel upgrade... Pulled permits as an "owner builder" when building my own house.

 

[zanydroid]

Do you know if formal plans, and city permit issued, are required by PG&E?

As far as I know, you can avoid this if you check the "Pre-engineering review" button in the form. At the very least, the website is coded so that it does not ask for the permits anymore once you check this button.

I did submit the SLD from my formal plans because my system did not match their stupid standard SLD.

But I've read that UL-1741 supplement "B" is adopted by California as of April 1st. Makes me wonder if the "A" but not "B" inverters on CEC's list will be disallowed as of that date. Better early than sorry?

Well. I figure they'll tell me by end of March (that would be 3 weeks of review) if they don't like HM series, and then I'll switch it to HMS and resubmit. I'm willing to gamble on that, it's a $600 difference in hardware for my installation size.

I think string inverters (having Rule-21 as required for new installs) will work well with low-frequency battery inverters that support AC coupling. There are high-frequency inverters too, but people say it is more difficult for those to do AC coupling.

IMO the reason to go with strings is so that you can DC couple it directly to a hybrid inverter of your choice (IE, removing your basic grid tie inverter), once the dust settles in the ecosystem and UL9540 becomes either not a price differentiator or gets deleted from the code.

Engineering wise, string inverters only require one component to reconfigure/replace if AC coupling doesn't do what you want. If you use microinverters, now you have 20 problems (or however many you installed). That said, since IMO it's impossible to know how the storage ecosystem will work out (and if you are 100% confident, go start a company or invest in some stocks, don't waste your time saving micro amounts of money on DIY), I decided to go with value priced microinverters to assure that a first time installer like me can finish the project, rather than try prognosticate & pick the perfect hardware for an unknown future.

I hope that's all. Drawings hold me up. (when they're not CAD I have and am familiar with, such as OrCAD at work.)

This is why I outsourced it to someone that does this CAD all day long and has the templates ready to go. Funnily my NEC calculations were better than theirs, and that required like 5 revisions to get the right numbers down.

 

[zanydroid]

I also emailed PGE yesterday asking a few questions to prevent, at least reduce, rejection(s). They took two days last time to reply. Received the reply yesterday, Saturday. Asking questions via email seems like a faster approach then submitting an application, waiting several days for possible rejection, resubmitting, waiting several days again... Time will tell of course

OK, that makes sense. Glad to hear that they're responsive. I have had good help from PG&E once I reach the right people. Though it's sometimes hard to know whether you have (and they don't always tell you you got the wrong department)

Regarding the optimizers. If SolarEdge instructions say you have to install them, you have to install them. Otherwise you are violating the listing / NEC. Listing tested it with optimizers/supported config. Electrical code says you have to respect what the manufacturer wrote down.

If you don't like SolarEdge markup you can consider Tigo. The hardware is not as capable as SE optimizers (no MPPT, limited current/voltage matching capability of 25% difference), but they are interoperable with multiple inverter companies. I'm not using Tigo because my abysmal shading situation strongly points to microinverters/individual MPPT rather than strings. As well, DC wiring requires special wiring methods that I was not sure I would understand enough to pull off on my own, when I locked my project parameters a few months ago. After lurking on this forum for a bit more, I'm more confident, but I locked it already.