array upgrade choices during re-roof, help me spend $$

[ultimatt]

I'm about to replace my roof, which means removing the 9.8kW solar array and replacing the panels on the new metal roof. I could replace the array exactly as permitted, but this tear-off, 3 inverter replacements, and having passed the "ROI" payback point a while back, this seems like a good time to consider the next decades of this arrays life.

Option #1: replace the array, except switch inverter to Sunny Boy 7.7-US ($3k), rewire array as ungrounded, and add (34) MPLEs (JMS-F or Tigo TS4-A-0) ($1.5k).

Why might I choose Tigo -vs- JMS-F -vs- other MLPE? Tigo for maybe better compatibility with next inverter?

Option #2: replace inverter with (34) enphase IQ7-60 micros @ $70 = $2.4k and an IQ Combiner 5 ($733).

Considering the 25 year warranty on the micros, that my 60-cell 290W panels are 8 years old with a likely output of (290 * .92 = 265W), and IQ7 cap of 250, this seems a reasonable option with not much clipping.

What should I be considering regarding an AC coupled array and a storage enabled future?

Option #3: one of them fancy new all-my-eggs-in-one-basket AIO hybrid inverters (Sol-Ark / Luxpower / Growatt) with support for solar, battery, transparent failover, generator, smart loads (EVSE!), and other fancy goodies all baked in. Sexy! (Cost: $3-6k + MLPEs + ???)

Option #4: Expand my mind. There's so much content on this site! Point me at threads that delve into topics and options I should be considering.

Goals:

• Islanding / battery / storage ready
  • low priority, grid is very reliable, typically 1 outage / year for half a day
  • the Big One (a 9.0) is coming on the Cascadia Subduction Zone, some islanding could be very useful
• Per panel production information, rapid shutdown, and optimization
• Capacity to expand the array
• Predictable cost / warranted components for life of the array
  • 25 years: Enphase
  • 10 years: Sunny Boy & Sol-Ark
  • 5 years: Luxpower & Growatt

Other thoughts:

In a rapidly evolving solar landscape where the manufacturer of my panels and inverter have both gone poof , I'm not excited by vendor lock-in. I will pay more to get more, but my tendency is to favor acquiring components (especially ones I don't "need") patiently and opportunistically.

For future emergency backup / islanding support, I'm thinking I can use the garage subpanel as my emergency loads panel. It has a heat pump for 1/3 of the house and we can run an extension cord to power the fridge. I have fire-resistant wall space in the garage to install electrical gear. To support growing the solar array AND a future bi-directional EVSE, I could upgrade the garage subpanel to a 225A rated bus.

Background:

• Location: Seattle, WA
• Highly efficient all-electric home, super-insulated, mini-split heat pumps, HPWH, EVSE
• Energy Consumption annual: house ~6,000 kWh , EV ~4,000 kWh
• Solar array: 9.8kW grounded
  • 34 panels, 290W iTek (17.3% eff)
  • Solectria PVI 7600TL grid-tied inverter (3rd in 8 years)
  • No MLPE, no rapid shutdown, no optimizers
  • Net metering
  • Shading: minimal, 12 panels face East & 22 face West, 18° tilt
• 2024 Electrical Overview
  • 200A main panel, 200A service
  • 125A garage subpanel, 100A fuse, aluminum feed
    • 40A solar (9.8kW)
    • 50A EVSE
    • 80A EVSE (wired, unused, bidirectional eventually)
  • 125A basement subpanel, 100A fuse, copper feed (heat pumps, water heater, kitchen)
  • 50A downstairs subpanel, 30A fuse, copper feed

 

[DIYrich]

Tl;dr

Look at the cost of adding batteries, and you will end up at option 3. Since you have a reliable grid, backup has less value, although half a day each year is significant to me.

Future proofing against net metering, or whatever the rate structure they come up with to minimize the cost of solar to the utility, has value. You can expand to a system where the grid is your backup.

Option 3 does require moving the inverter to be near the main panel (sits between meter and Main panel). Pv wires too. But re-roofing is the time to do that.

 

[TechRider]

I just finished a new install that is basically Option 3. I love it! Just got my first power bill and it was much much lower. I like the option of switching to offgrid without issue. We had a brief power outage when someone hit a pole down the road and if my generator didn't kick on, I wouldn't have know. We also recently went through multiple 100+° days and I felt a lot less guilty that the AC was running most of the time.

I personally have the Sol-Ark 15k. I like the fact that you can add AC coupled solar to soft expand the system later if you want.