Parallel Solark 15k, no interconnect agreement.

[Ampster]

If you have a 10kw inverter, but overpanel the living shit out of it (let's just say 30kw to make it exaggerated), according the the power company, do you have a 10kw system or a 30kw system?

Good question. My NEM agreement refers to both the PV panel capacity and the inverter capacity. The section @Hedges posted above may be how the utility covers their bases.

There is a member of another forum who has a system like that but it is all ground mount and at various orientations so he never sees much clipping but has a much longer period of generation during the day. I have never asked him what the limit of his NEM agreement is. He is in rural Illinois.

 

[zanydroid]

Interesting. If you have a 10kw inverter, but overpanel the living shit out of it (let's just say 30kw to make it exaggerated), according the the power company, do you have a 10kw system or a 30kw system?

I'm working on my interconnection application with PG&E right now, and it has a lot more places where you fill in the DC size (and extrapolated output) than it does the AC size. As well, the 2021 NEM3 proposal (which got rejected) added a monthly fee proportional to your DC size.

IOW it's very clear to me that the POCO here cares a lot about the DC size.

In fact I'm hitting some confusion in manual-entry fields about whether you are supposed to adjust AC size to by overpaneling %. For the auto-calculated part of the form, I don't really care, it's their own fault if their webapp logic calculates something nonsensical.

 

[Ampster]

In fact I'm hitting some confusion in manual-entry fields about whether you are supposed to adjust AC size to by overpaneling %.

The DC size divided by the Inverter size is the DC to AC ratio (overpaneling %). Why would one reduce the AC size below its actual value? Then, on a day that your inverter is putting out 100 percent it could look to them that you have added capacity if their records show a lower AC value.

 

[zanydroid]

The DC size divided by the Inverter size is the DC to AC ratio (overpaneling %). Why would one reduce the AC size below its actual value? Then, on a day that your inverter is putting out 100 percent it could look to them that you have added capacity if their records show a lower AC value.

I just meant, it's not clear to me which parts of the form use the DC * CEC efficiency rating calculation.

And which parts want you to take into account the actual AC output limit due to overpaneling, which will be lower than that.

 

[Hedges]

PG&E needs to be concerned with the maximum AC power you can deliver. That is what their local distribution network has to handle.

Overpaneling just extends the hours and seasons when that can occur. Should not be any concern of theirs, except it represents more kWh you will net meter. A financial issue, not a technical one.

But they do let you add storage inverter later, which could support 3x the export amount (since they say its inverter can be up to 2x PV inverter.) You would need DC coupling not AC as I have to best utilize overpaneling.

 

[Ampster]

it's not clear to me which parts of the form use the DC * CEC efficiency rating calculation.

Are we looking at the same form? (Form79-1151B)
On page 3 of that form there are two columns to enter PV capacity, the first one is "Nameplate Rating kW/unit" and the second column is "PTC Rating kW/unit". The footnote says the PTC ratings are available at consumerenergycenter.org
The CEC Ratings are the next row above the PV row and are for Inverters.

 

[ImAnIdiotPleaseBePatient]

The DC size divided by the Inverter size is the DC to AC ratio (overpaneling %). Why would one reduce the AC size below its actual value? Then, on a day that your inverter is putting out 100 percent it could look to them that you have added capacity if their records show a lower AC value.

So I got a hold of FPL and they said they go by the AC side of things, so overpaneling is aok for a tier 1. They only care about output from the inverter.

Also talked to Sarasota and the said Danke was 100% correct. Self install is aok so long as you dont sell before 2 years after the install.

 

[zanydroid]

Page 3 is super clear, and it's auto-filled from CEC equipment data / internal logic on the webapp.

There is another form that has the total AC kW of the facility, that is not auto-filled.

 

[zanydroid]

Also talked to Sarasota and the said Danke was 100% correct. Self install is aok so long as you dont sell before 2 years after the install.

OK that's great.

The anti-flipping clause is pretty common in the US. EG you can't buy a place and remodel all of it in 3 months without contractors, and sell it. Which I presume means effective flipping in jurisdictions that have this clause require you to have a GC license.

 

[zanydroid]

PG&E needs to be concerned with the maximum AC power you can deliver. That is what their local distribution network has to handle.

Theoretically if the average duration of peak power is longer, the wires/transformers will see more heating. And having more panels behind the same AC output will extend this time.

If they have a large enough buffer between peak power vs the available capacity in the system, at the times that PV is being generated, then the duration does not matter.

 

[Ampster]

There is another form that has the total AC kW of the facility, that is not auto-filled.

In that case, I presume one would use the CEC numbers.

 

[Danke]

So I got a hold of FPL and they said they go by the AC side of things, so overpaneling is aok for a tier 1. They only care about output from the inverter.

Also talked to Sarasota and the said Danke was 100% correct. Self install is aok so long as you dont sell before 2 years after the install.

A local installer here told me they go off of AC also. So he usually installs micro inverters that are under powered for the panel and excepts a little clipping around noon on some days. That way you can put more panels up and produce more power throughout the day/year.

 

[zanydroid]

In that case, I presume one would use the CEC numbers.

Yes I just looked up the paper form and it is CEC number, ignoring the overpaneling ratio. I'll double check again when WebApp renders the PDF to sign how the webapp maps to the form. It's not clear in a number of places. But the PDF signature page is a good final check.

 

[goldserve]

Skimming through this thread, I have the very same dilemma Ampster and others have. I have an interconnect agreement for a small system back from 2014. I’ve since connected it to dc input on the outback skybox and have a much larger ac coupled to the critical loads side. The skybox can curtail its own pv power to stay under the export limit but what will happen when the ac couple array makes more than the limit. I also don’t like the idea of throwing away power so I am reading the enphase envoy CTs, figuring out the current export and doing some math and publishing to mttq server so the openevse will follow the curve and dump the rest into my ev. The math allows me to guarantee the minimum amount to export so the solar divert function of the ev charger won’t take all the available power.

Let me know if anyone want more details.

 

[ImAnIdiotPleaseBePatient]

Well, now we are back full circle to the original idea, but adding the interconnect agreement.

-2 solarks,
-my 64 qcells from china (if they arrive)
-64 rsd (im lazy and want to power it from the solark 12v, so no monitoring), along with one or two TAPs and a keep-alive signaller.

No batteries to start, but i have big plans for that later (saving money in case I get myself into trouble and need to hire out for competance)

going to permit the whole damn thing, since its possible. i need a $1,000,000 insurance policy per florida regs. hope it isnt that expensive ?

 

[Hedges]

Dr. DeSantis:

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[ImAnIdiotPleaseBePatient]

Dr. DeSantis:

dr evil one million dollars - Search Videos

www.bing.com

Fortunately, it's just a personal liability policy. I can't imagine if they required collision and comprehensive ?

 

[zanydroid]

-64 rsd (im lazy and want to power it from the solark 12v, so no monitoring), along with one or two TAPs and a keep-alive signaller.

I think the CCA/TAPs are only needed for the monitoring / optimizer types.

If you have the RSD only type you just need the keep-alive. And if the Sol-Ark has the transmitter in it then you won't need that.

 

[ImAnIdiotPleaseBePatient]

I think the CCA/TAPs are only needed for the monitoring / optimizer types.

If you have the RSD only type you just need the keep-alive. And if the Sol-Ark has the transmitter in it then you won't need that.

Solark is missing the transmitter. I don't need the CCA for sure, but I think the transmitter does powerline comms to the TAP, which wirelessly sends the keep-alive to the actual RSD units. I could be mistaken on this one. Solark just has the 12v power supply, which is enough for the transmitter, but not enough power for the CCA (if you wanted monitoring/optimization).

 

[ImAnIdiotPleaseBePatient]

Going to have two brand new Deye 16k's for sale here in a month or so ?