Need to hire a solar consultant with LA/California experience

[rwhite8134]

I wouldn't recommend Solar Edge for a solution with batteries because you are forced to use their very expensive batteries. However, the single solar input isn't a restriction. Each panel gets and optimizer which means you've got a good MPPT on each and every panel, you can have strings facing in every direction and partial shading, each panel will still produce at their peak.

I was planning on using the TS4-A-F (RSS) and not the TS4-A-O MLPE as it seemed that recent modules do so well themselves with shading anyway. I recall coming across a YT video of someone comparing two side by side modules with and without a TS4-A-O and the one without the Tigo produced more with identical shading. Not hard evidence of course but was interesting. Can't seem to locate the video now though. If the consensus is that optimizers indeed make a difference, either with shading or fewer trackers the extra cost is worth it over a RSS only MLPE.

Yes, you'd need more individual inverters if you go with the Schneider, but the individual inverters cost half the price. And you can customize the system to exactly your needs. Want more solar? Add more charge controllers.
Also, if something fails, you can pull that single component and not take down major sections of your system.

You've got a great point there. However the Schneider MPPT controllers appear to have a single tracker from what I can tell, I can't see it spelled out exactly, but if optimizers would solve that then I guess the Schneider is back at the top of the list.

 

[rwhite8134]

CEC list and interconnection app is 95% accurate esp for new equipment. Hedges on the forum here got tagged for using an older inverter (and he was allowed by the app to file an application), but he collects inverters and has other options so it wasn’t a big deal. Unfortunately I don’t know how you can derisk further besides delaying buying the equipment until you get full permit and PG&E pre review done.

Ahh, so even if it is on CEC list and passes AHJ plan/permit SCE could still prevent it with/during their Interconnection application or review process? Hmm, well for this first install stage on detached garage alone I wouldn't want or be doing an Interconnection agreement with SCE unless I will be forced to, which will change absolutely everything. I was hoping to only have to deal with Interconnection when we add PV to the house next year and connect the house to the garage equipment.

I expect doing it all at once later is cheaper. Single interconnect, permit review, and planset fee, which would save probably $800 at least to do in one shot.

Yea, sigh, I know. Even an extra $800 or so still makes sense to us with the logistics of tax credits/rebates and FHA home improvement availability stuff next year.

 

[zanydroid]

I was planning on using the TS4-A-F (RSS) and not the TS4-A-O MLPE as it seemed that recent modules do so well themselves with shading anyway. I recall coming across a YT video of someone comparing two side by side modules with and without a TS4-A-O and the one without the Tigo produced more with identical shading. Not hard evidence of course but was interesting. Can't seem to locate the video now though. If the consensus is that optimizers indeed make a difference, either with shading or fewer trackers the extra cost is worth it over a RSS only MLPE.

Half cut solar modules do better with shading if you believe that MPPT will not be confused with the more complex tracking that may need to be done.

IMO the only consensus is that optimizers and microinverters eliminate the risk of messing up production with wrong string layout design. I may be being an asshole here, but I kind of assume that a lot of installers in California/the US like optimizers and microinverters because they can both take a higher profit on margin, and not have to do any detailed design (the modules will self correct).

With a proper layout and a site that is suitable for solar bypass diodes are theoretically fine by themselves, and half cut makes them a bit better. (The string companies like Fronius have software and marketing around this). I have an installation with microinverters because the shading is kind of insane… but the real question is why I even bother with solar modules in the first place.

That said optimizers and microinverters can potentially reduce the amount of time bypass diodes embedded in modules are activated and therefore subject to thermal stress. They’re a failure point for modules. Could also reduce the bypass current.

You've got a great point there. However the Schneider MPPT controllers appear to have a single tracker from what I can tell, I can't see it spelled out exactly, but if optimizers would solve that then I guess the Schneider is back at the top of the list.

So optimizers are about the most complicated class of solar devices out there. There are two classes on the market now. SolarEdge and the bleeding edge SolArk one provide a MPPT tracker and wide adjustment range DC DC converter to match current and voltage. TIGO do not have MPPT tracker so they likely are not a good idea to put on separate planes. They also have a marcher that only adjusts 20-30% (my theory is that this allows them to not require custom control logic on string inverters, since solar modules themselves have a 30% adjustment of sorts by activating bypass diodes).

 

[zanydroid]

Ahh, so even if it is on CEC list and passes AHJ plan/permit SCE could still prevent it with/during their Interconnection application or review process.

They could reject it because of a typo in the information or code, or because there’s a transformer limit. There’s little way to derisk this — you can’t call up the engineering office and expect them to give much help without an active application.

Hmm, well for this first install stage on detached garage alone I wouldn't want or be doing an Interconnection agreement with SCE unless I will be forced to

You can do that as long as you either have a risk tolerance for an unapproved parallel setup (using zero export to hide), or know how to pick equipment that works fine off grid and later transition to on grid. Off hand the easiest way maybe is to use an external AC charger to charge the battery instead of directly connecting to grid. This would be fine from a POCO angle but it will violate UL9540 rules on ESS because there are pretty much zero approved chargers unless you buy a second UL9540 hybrid ($$$$$) and use it exclusively for charging. Again this somewhat boils down to a risk tolerance for doing not what your supposed to do

And a risk tolerance for the equipment being rejected due to you or your designer misunderstanding various technical things.

I feel the amount of extra work it will take you to understand the engineering / design will outweigh the benefit of skipping the first interconnect review.

 

[zanydroid]

They could reject it because of a typo in the information or code, or because there’s a transformer limit. There’s little way to derisk this — you can’t call up the engineering office and expect them to give much help without an active application.

That said, if you go with a hybrid someone in California with your POCO has already approved, and has an export limit option, you’re probably safe from typos and transformer capacity.

I’m not sure about typos in approved solar panel list. I can’t see why the POCO would care. And solar panel choice is a building department safety thing…

 

[rwhite8134]

You can do that as long as you either have a risk tolerance for an unapproved parallel setup (using zero export to hide), or know how to pick equipment that works fine off grid and later transition to on grid. Off hand the easiest way maybe is to use an external AC charger to charge the battery instead of directly connecting to grid. This would be fine from a POCO angle but it will violate UL9540 rules on ESS because there are pretty much zero approved chargers unless you buy a second UL9540 hybrid ($$$$$) and use it exclusively for charging. Again this somewhat boils down to a risk tolerance for doing not what your supposed to do

And a risk tolerance for the equipment being rejected due to you or your designer misunderstanding various technical things.

I feel the amount of extra work it will take you to understand the engineering / design will outweigh the benefit of skipping the first interconnect review.

The garage loads are non-critical. I wouldn't even care about charging the battery via AC/grid. Whatever PV makes I could use and/or store. When we get to the point next year of installing PV on the house and connecting critical house loads to the inverter(s) then doing Interconnection would make sense. But I totally get your point that if I already purchased inverter(s) and POCO says no-no next year then I got to get something else.

Good food for thought. I really appreciate the input guys.

 

[zanydroid]

The garage loads are non-critical. I wouldn't even care about charging the battery via AC/grid. Whatever PV makes I could use and/or store.

Then this is fine. You can buy like a SolArk and set it up without a grid connection and have no risk. If the POCO asks why there are solar panels on the roof without a interconnect agreement you can tell them it’s not interconnected.

I personally would be OK with just buying CEC listed modules after getting sign off from AHJ (including fire setback review).

 

[400bird]

They could reject it because of a typo in the information or code, or because there’s a transformer limit. There’s little way to derisk this — you can’t call up the engineering office and expect them to give much help without an active application.

PGE did this for me in 2018
Not sure if they still do it now, but a phone call doesn't cost much to try and find out.

You've got a great point there. However the Schneider MPPT controllers appear to have a single tracker from what I can tell, I can't see it spelled out exactly, but if optimizers would solve that then I guess the Schneider is back at the top of the list.

Each charge controller is a single MPPT, but you aren't limited to one charge controller. You could add 5 if you need.

 

[Siamac]

Here are a couple aerials:

View attachment 170243


View attachment 170244

How did you get the heat map?