semi DIY Expanding or replacing current solar system in CA?

[rpatel18]

Hello, I'm looking for some help on either replacing or adding to the current solar system my in-laws have in their house in Bakersfield, CA. This system was already installed when we purchased the house back in 2017. It has 20 panels that are 100w and the only info I have is that the inverter has the brand "Sunny Boy SMA Technologie AG" (yes, technology is spelled like that on the inverter) is out of business. The company that installed it, Pure Energy Systems is also no longer in business.

They recently just got a heat pump, are looking to buy in EV in the next 2 years, and are most likely going to switch to an electric stove. I'm also getting an Emporia energy monitor in their panel so we can track energy use more in real time to gauge how much power they need now and in the future.

Our main goal would be to have enough solar production and battery storage where we rarely pull from the grid, selling access energy back is great but our primary focus is to just not pull from the grid as much as we can. We also are on PGE and NEM 2 and I also think this would cause us to move to NEM 3.

We want to go a "semi" DIY route where we get the equipment but get help installing in, schematics, and architecture plans. Anyone have any advice on how to approach this or have anyone they can recommend in the area?

 

[darrell2002]

2kw of old panels is not going to get you too far in trying to not pull too much from the grid. Is the system functional? I'm guessing that any alterations would put you into the far less favorable NEM3, which really requires a large battery to be at all usable and a new inverter.
It's either a complete redo or just live with what you have I think. Installers are generally not interested in semi DIY. They have a formula that works and generally are not going to go out of their way to accommodate a DIY type user. Maybe you could act as the general contractor and sub out what you can't do yourself, but there is a mountain of things to learn to get to that point. It can be done, but you have to have a lot of drive and patience

 

[Siamac]

If you have access to the roof or somewhere to install more panels yourself, ideally ground mount, then you can easily piggy back it to the current system. You will need to have an electrician wire it to the grid or if you have electrical knowledge, probably can do it yourself. If you can replace the current panels with 300-400 watt panels, can use the same mounting and just replace the sunny boy. But the wiring needs to be big enough to handle it, otherwise you need to replace those too.

It's a big project, but not as bad as it sounds if you do little by little

 

[teal95]

Add a second system.

 

[Lawrence_SoCal]

There is a new-ish CA agreement amongst solar vendors and CA utilities to enable adding non-exporting PV capacity and staying with your current net metering (a number of other recent threads on this in last month or 2)
I've read in detail on the Enphase AC-coupled solution. I assume there are others? basically, you get a software controlled limit to control exporting (so you can't export than current agreement allows). My understanding is that the Enphase system has a CT watching grid export, and will throttle (curtail) PV production on new PV system to avoid excess exporting. Obviously battery/EV charging during max solar production becomes ideal... depends on willingness and ability to configure/control/automate such electrical usage as to getting max benefit. Others talk of a dump load .. like electrical hot water heater to consume excess PV)

Do you have the original interconnection agreement? it was recent enough, I'd expect it specified the expected kW capacity of the system (not the 100W marketing #, but the typical for that location expected max output)
1. I'd see how close to that number you are getting at exporting now? why? the new plan will limit export for NEM2 to the interconnection agreement amount. But if you weren't hitting that number already, there may be some fudge room

I tend to be a rule follower... when the rules are reasonable/prudent/etc. Stupid rules... not really my thing
I mention as it may be cost effective to replace some (many/most/all) of those 100W panels with newer 400+W panels (checking sizing, have changed over time). The rules are for a new system, but realistically, the PoCo doesn't really have a way to know where the electricity is coming from. But, if you contract this out, most businesses will not want to risk being able to do future business by bending the rules... just something to be aware of

Other thoughts
- be sure EV changer is one that can be configured/controlled to limit charge rate (to only using available excess solar, or ensuring entire house grid draw is only X amps, etc).. this will cost a little extra (maybe)... but potentially save main load center upgrades

I'm not sure of details, but this is maybe something where the Tesla battery would play well (and maybe others?) ... old DC-coupled panels direct to Tesla battery inverter (bypass Sunny Boy completely)... and Tesla Battery has integrations with Enphase AC-coupled panel systems (if that is plan requirement to stay on old NEM plan). Then replace old panels if/when ready, and use automation/controls to limit exporting, even though greatly increasing PV production capacity. This would work especially well assuming in-laws can/usually would EV charge during the day (vs overnight)

 

[CaliSunHarvester]

Sunny Boy SMA Technologie AG

That company is still around. The name is German. I had 2 inverters from them.

@Hedges knows a lot about them.

 

[zanydroid]

This NEM2 expansion via no export hack is a new topic to this forum

I would suggest you try making some CALSSA , r/solar , r/enphase friends since you’re on the bleeding edge. And cross pollinate any information you learn. And have a zen attitude about when you’ll be able to get this done / be smart about delaying equipment purchases until you’ve locked down the approvals

Good luck

 

[Hedges]

100W panels. My first system was 24x 120W panels and 2500W SMA inverter.
I'd think it is over 20 years old and you will be pushed onto Solar Billing Plan (NEM 3.0) at next true-up.

What you've got will offset consumption reducing draw from grid. NEM 3.0 credits are so small as to not help.

Plan your consumption, production, storage and select prospective equipment.
That could be EG4 18kpv, SolArk, Midnight The One, SMA SBSE, etc. for grid-interactive hybrid.
Midnight Rosie (not sure how interactive), SMA Sunny Island (not interactive), Schneider for traditional backup system or off-grid.

Possibly you will be better off decommissioning what you've got, switching to tiered not time of use plan, installing zero-export or off-grid system.

Grid tied was so much easier (grid handles surge) but we have to adapt to PUC changes.

There are companies that specialize in drawing plans and offer engineer stamping of them.
I saw such on Santan Solar's site, and people mention others.
Requirements vary by city; some want more detailed structural design than others.

For the trades, SolarAPP+ simplifies it to answering questions on a website. But that is only for when contractors get the permit.

You might find a small installer who will let you be your own labor.
But buying hardware and hiring out the work, pretty much impossible it seems. Companies want the markup and don't want to be responsible for equipment you buy.

Any reason not to do the work yourself?
Possibly having a roofing contractor do some or all of the mechanical install on the roof?

 

[zanydroid]

We want to go a "semi" DIY route where we get the equipment but get help installing in, schematics, and architecture plans. Anyone have any advice on how to approach this or have anyone they can recommend in the area?

I agree with Hedges that it is probably challenging to find someone to install your provided equipment. It is not viable in the Bay Area, though one person on the forum did it in one of the north counties. Schematics and architecture are quite easy to outsource anywhere in the U.S., due to plethora of online services that do this for you.

However it’s possible Bakersfield is a different story from Bay Area.

Also I noticed this is not your house but a family members. You will have to do some legal gymnastics to qualify as an owner builder since you aren’t an owner builder (you can GC and do electrical on your own house in California unless otherwise prohibited by local law. Electrical has extra constraints on who is allowed to do it on what property in California. IIRC Hedges (maybe someone else?) has made this work somehow.

 

[Lawrence_SoCal]

house in Bakersfield, CA. This [PV] system was already installed when .. [house] purchased ... in 2017. It has 20 panels that are 100w

One thing to add to thought process. Before considering the allowed [so not really a 'hack', imo ;^)] PV system expansion with caveats, without re-tariff'ing, I'd look into details of when the current NetMetering agreement for the house expires. There is little point in working around limits, etc, if in a couple of years, you'll be kicked to NEM3 anyway (if original install was approx 20 yrs ago)
And how is the roof? when is it likely to need serious maintenance (ie lift 'n lay, or re-roof, as applies to that house)? What you don't want to do is a bunch of solar changes now, and then in a couple of years need to take it all off the roof for roof work, then put it back up, especially if nearing end of NEM agreement (As @Hedges mentioned).

No one wants to hear this, but assuming reaching end of your NEM agreement, then replacing the entire system probably most financially practical (due to limited roof space? vs ground mount in largely unshaded area... just guessing)
- and probably makes sense to do long-term roof maint while you are at it
- Then put up basically new system (as I doubt much of 20 yr old system is worth keeping) on NEM3, meaning a house battery will also be part of the project... ugh, adds up fast.

Now, if for some reason, their roof won't need any work for next 20+ years, and soon to be kicked off existing NEM agreement, maybe
- remove all panels and replace with panels of choice, new wiring, into new hybrid Inverter and battery... just beware new panel sizing, and impact to mounting/roof

As for Electric stove... depends on PV production and battery storage you have. Sticking with natural gas, may pencil out better (at least for now)... don't forget cost of running 240V electrical into kitchen (in my case, 2-story house on slab... complete PITA. ymmv)
also, beware kitchen remodel that dictates bring kitchen up to new electrical code compliance standards [not trivial for my 45yr old house]