Anyone done the Enphase legacy upgrade?

[RussTTU]

I bought a house a couple years ago that already had a ground mount grid tie enphase system installed. My primary desire to upgrade the system is to increase my resiliency during a grid down scenario. Also, the purchase power agreement i have with my coop is garbage, so I might as well use the power I produce rather than selling it at a 90% discount.

My current system has 40 (235 watt) panels with micro inverters and the envoy gateway internet monitoring. I want to upgrade the system as the micro inverters only allow 215 watts to pass though and it has no battery back up.

The options I am contemplating are:

1-Upgrade only the micro inverters to iq8 or iq7s and adding the enphase battery backup. This would increase the power of the system from 8.6 to 9.5kw. This is still relatively small for my needs but i could make it work.

2- Upgrade both the micros and panels to at least 400 watt which would make the system 16kw and be plenty powerful for my needs. Include the enphase battery backup but start smaller as the system gets expensive fast.

3- Add a completely new system to my roof. I would still like to make it a hybrid system that would use power from the system before the grid. I don't have to use enphase at this point and can be more flexible and get more bang for the buck.

Does anyone have any strong feelings either way about these options?

Appreciate the input.

 

[Surferdudemi]

I bought the IQ7+ upgrade. Had a bunch of older Enphase micros that keep failing one by one (four so far out of 10, I think). That likely why they are offering the upgrade. I have Sharp 175W panels right now, so I got the micros that are compatible with the existing panels. However, the panels are now over 10 years old, and the newer panels are more efficient, so considering if I want to try to swap out the panels as well. The problem is that the form factor has also changed, so I would have trouble fitting the new larger panels on the roof section (it's A-shaped).

My current plan is to put up the microinverters to replace the GT3.0 inverter I'm using (was only testing out the older Enphase on the ground) to avoid having to put in a remote disconnect, and installing an Outback Skybox with DIY LiFePO4 battery bank for backup. Still have to confirm with the power company and inspector that I can do this (without the DIY battery bank initially). Inspector said if I touch it, everything has to be brought up to latest code (i.e., cannot just swap in the Skybox).

Depending on the age of your system, it may be worthwhile to do option 3. Remember that there's still the 26% tax credit on new components, so there's a built-in incentive for the upgrade.

 

[400bird]

My current system has 40 (235 watt) panels with micro inverters and the envoy gateway internet monitoring. I want to upgrade the system as the micro inverters only allow 215 watts to pass though and it has no battery back up.

The options I am contemplating are:

1-Upgrade only the micro inverters to iq8 or iq7s and adding the enphase battery backup. This would increase the power of the system from 8.6 to 9.5kw. This is still relatively small for my needs but i could make it work.

If this option is using the same 40 235 panels, you're not going to get any increase in production. The 235 watt rating is in ideal laboratory settings, you'll get 80% of the that in the real world.

You probably aren't even maxing out the 215 watt micro inverters currently in place

 

[caki]

Adding to what @400bird said, you can see if your inverter is clipping production by looking at the graph of production. If it is flat at the top, it means you are clipping. This link explains it in a lot of detail: https://www4.enphase.com/en-us/support/technical-brief-sizing-solar-modules-microinverters
Anyway, another point I want to make is that unless you have a reliability issue, upgrading a solar system would invalidate its ROI, so I think it makes sense to expand it and keep the old system for its useful life. We are all trying to save the planet by using less and using renewable energy. If we keep on trowing old panels/inverters that are still producing and installing new ones we may not be contributing much to the solution.
I'm in a similar situation. I have 250W panels with M215 inverters. I was also tempted to just upgrade to the latest and greatest, but I have made the decision of expanding using new panels and inverters instead of replacing what is there already and paid off.

So I would say go for option 3.

 

[RussTTU]

You make some good points regarding not replacing functioning equipment. However, my p[rimary reason for wanting to upgrade is to have a resiliant power source during a grid down scenario. I think I have decided to add on to my system instead of replacing my current panels, even though it would be so much easier and not require me to put anything on the roof of my house.

The main problem with my current system is that is is only grid tie and the m215's will not work with the enphase enchage battery system. I am not even sure if it will work with any battery system on the market. So if I want to have a functioning system during a power outage, I will need to spend close to $4,000 to upgrade the m215's to the iq7a's.

I have the room to add up to 12kw of additional power, which may be sufficient for my purposes, but you never know when that extra 8kw will make a difference or not.

 

[caki]

Actually, you can now just add the Enphase battery to M Series inverters:

https://www4.enphase.com/en-us/stories/enphase-storage-now-compatible-enphase-m-series-microinverters-installers

So if you want to have a backup, that seems to be the way to go for about the same price as the upgrade to IQ7. What state are you in?

 

[RussTTU]

Texas