How easy is it to add 6 panels to this system?

[bradmtb]

I had a 6 panel micro inverter system installed last summer, knowing I'd probably add additional panels in the future.
The future is now, as I just leased a Fiat 500e EV, and want to consider doubling the size of my system.
I have 6 240w panels (Canadian Solar CS6P-235Px), and 6 Enphase M215-60-2LL-S2x micro inverters.
I was shopping on the internet, and found the same panels and micro inverters at a reasonable price.
Are there things I should be concerned about?
Do I need to pull permits to add to my system?
Any ideas of who I should hire to install the add-ons?
What's involved in adding the 6 panels and micro inverters?

[Naptown]

You could add 11 more to the system with what you already have there.

You will probably have to permit and another interconnect agreement all over again.
Nothing else special other than perhaps a trunk cable splice kit.

You do not have to stay with 235's you could use a higher watt panel like a
250 which are the same size

[bradmtb]

I talked to a solar supplier, and they were suggesting going with 250w panels of another brand, Enphase M215 micro inverters, and using an optimizer.
They were suggesting mounting a new rack of panels (not tied to the 6 I have, and then running a separate line to my electric panel).
I would prefer not having to run anything down to my electric panel, and just "splicing" into the exist line of 6 panels. If I added 10 panels, could
I just splice in 2 panels along the 6 I have already, and then splice and mount another row of 8 just below.
Punching another hole in my roof to run another cable and conduit down to my electric panel seems like a lot of extra work and cost.

[Naptown]

Whoever told you that fairy tale should be drummed out of the business
You do not need optimizers with an Enphase system.
Look at where the solar ties into your panel and tell me what size circuit breaker the solar connection is

[bradmtb]

It appears that the solar circuit on my electrical panel is 4- 20 amp breakers. I have plenty of roof space to expand my 6 panels to 16. Two rows of 8 would be my choice configuration. The original solar company that installed my small system would love to do the expansion, however, I don't want to pay that much. While I consider myself a "solar novice," I would prefer researching my options and educating myself as much as possible on this forum, and then consider buying the materials on my own, and hiring a licensed electrician or installer to help me.

[Naptown]

Why 4 breakers in the panel.
Only 2 are necessary.

[bradmtb]

Maybe it is 2 breakers? Here's the picture of the breaker at the panel.

[inetdog]

Maybe it is 2 breakers? Here's the picture of the breaker at the panel.

It looks like only the two center breakers, with the handle tie, are the solar backfeed. The outer two may be unused or spares or used for other unlabelled circuits. Your single wiring harness only needs a single 240v breaker connection, which is what the two with their handles tied together provide.
From the fine print, even the two handle-tied breakers do not have a common trip, which is OK for the microinverters but could be an issue with the AHJ for string inverters. The handle tie just makes sure that when you want to disconnect the micros you remove all power from the harness, not just half of it.

[SunEagle]

It looks like only the two center breakers, with the handle tie, are the solar backfeed. The outer two may be unused or spares or used for other unlabelled circuits. Your single wiring harness only needs a single 240v breaker connection, which is what the two with their handles tied together provide.
From the fine print, even the two handle-tied breakers do not have a common trip, which is OK for the microinverters but could be an issue with the AHJ for string inverters. The handle tie just makes sure that when you want to disconnect the micros you remove all power from the harness, not just half of it.

It looks like the electrician removed 2 standard width breakers and replaced them with 4 half width 20 amp breakers. This way he could use the middle 2 breakers which are connected to each phase of the 240 volt panel for the solar system connection.

[bradmtb]

My current 6 panel system which is a single row consisting of:

6- Canadian Solar 235W CS6P-235PX panels
6- Enphase M215-60-2LL-S2X micro inverters

So is adding 6-10 additional panels, similar (although using 240-250w panels) to my existing ones, Enpahase M215 micro inverters, a trunk cable splice kit, rack kit, permits, and interconnect agreement all that I need to expand my system?
Does any upgrade or addition need to be made at my breaker panel?
I'm hoping to purchase the materials through an online wholesaler, and then hire a local licensed solar installer.
My original 6 panel system was installed in a day, and I'm guessing the labor cost, plus markup on materials cost me $8,000+.
I've priced out a 10 panel 2450w system for about $4,500. I have not got quotes for labor.

[Naptown]

What is the size of the service?
Anything over 100 amp should be done with no further upgrade needed.

[bradmtb]

It's a 200amp service panel

[Naptown]

Then no problem adding on
You could add 28more panels to your service but only 11 more to the circuit you have

I edited to clarify

[MGE]

Tell the installer what you want to have done is this. Add (6) additional panels to the existing array. No new conduit needed just have them mount a j-box to the end of the existing trunk cable (which should have a end cap installed) and tie in a new trunk cable for the new panels, mount new rails, ground as required (irreversable splice) connection, mount inverters and panels and your set. You will have to pull a permit for the additional panels and let the utility know also. A 200 amp panel can take (2)-20a 2 pole breakers loaded up to 80% (16amps). Example: I have (2) 2 pole 20a breakers mounted in my 200a service panel and I have (34) 260w panels rated at 86% efficiency . Which means I have 2 sets of (17) panels per breaker. So 17 X 260w = 4420w X .86% = 3801.2w divided by 240v =15.83a per breaker. This takes into account full production of all panels at there max rating. Good luck should be fairly simple install.