Enphase IQ8 & Powerwall add on

[Rootcanal1]

My current system is approximately 8kw with a Solar Edge inverter with two Powerwall 2's, it's only 6 yrs old.

I want to expand my system by adding another powerwall and 8kw of Enphase IQ8, so I can (island) charge my batteries or home when the grid goes down. I spoke to a couple of solar companies and they don't seem to think the two solar system can work together. Does anyone have advice on how to get this accomplished.

Thanks Mark

 

[mswlogo]

They would be two independent systems.

 

[lodar]

My current system is approximately 8kw with a Solar Edge inverter with two Powerwall 2's, it's only 6 yrs old.

Solar Edge takes DC power from your panels and converts them to AC in the big box on your wall.

I want to expand my system by adding another powerwall and 8kw of Enphase IQ8, so I can (island) charge my batteries or home when the grid goes down.

Enphase IQ8 are “microinverters”, they convert DC to AC at the solar panel. The big beige box just controls and configures the microinverters.

I spoke to a couple of solar companies and they don't seem to think the two solar system can work together.

You certainly cannot add IQ8s to the Solar Edge directly. But, you should be able to put an entirely separate Enphase system next to it, as long as you have enough wall, roof, conduit space, etc…

 

[cali8484]

I want to expand my system by adding another powerwall and 8kw of Enphase IQ8, so I can (island) charge my batteries or home when the grid goes down.

What do you expect this system to accomplish that the SolarEdge/Powerwall system could not?

 

[Tazzman]

Do you have the gateway with your current system? You will need CT's on the Enphase part connected to your existing system so the Powerwalls know that energy is there and how to handle it on and off grid.

 

[lodar]

I had an IQ8 expansion added next to my existing IQ7. Not quite the same as totally different brands. But, they were totally separate and came together at the Tesla Gateway.

Regarding CTs, they clamped both solar systems to the same CT as long as there is enough slack in the power cables.

 

[Rootcanal1]

What do you expect this system to accomplish that the SolarEdge/Powerwall system could not?

The IQ8 are able to provide power when the grid is down either by recharging the batteries or powering the house. With my SolarEdge as soon as the grid goes down solar production stops and then I just have to try and stretch out my battery power till grid gets reconnected.

 

[Rootcanal1]

They would be two independent systems

 

[Rootcanal1]

What I would be hoping they both feed into my power walls. I would like the third powerwall im going to be purchasing to be part of one powerwall block. I love how easy it is to use the powerwall app

 

[Rootcanal1]

Do you have the gateway with your current system? You will need CT's on the Enphase part connected to your existing system so the Powerwalls know that energy is there and how to handle it on and off grid.

Yes I have a gateway. So I thought it would be reasonably easy to add another powerwall to the system along with solar panels with the IQ8 so I could keep charging during grid outages.

 

[cali8484]

The IQ8 are able to provide power when the grid is down either by recharging the batteries or powering the house. With my SolarEdge as soon as the grid goes down solar production stops and then I just have to try and stretch out my battery power till grid gets reconnected.

So, that's the "Sunlight backup" feature of iQ8. Unfortunately, that feature is not compatible with Powerwalls. You would need to use Enphase home batteries in a separate system. Powerwalls form and control the island grid when utility power goes down so iQ8 can't have the control to enable Sunlight backup. Since you already have SolarEdge/Powerwalls I still don't see what iQ8's add since the Powerwalls should already enable the SolarEdge to continue to produce power during grid outages.

 

[Tazzman]

There are plenty of people who have a mixed system here and it works fine as long as it is done properly. I'm not familiar with Solar Edge but I believe it should be able to operate while your system is off grid as long as your batteries are less than 95% the batteries should put out a healthy frequency to keep your inverter producing.

 

[Rootcanal1]

So, that's the "Sunlight backup" feature of iQ8. Unfortunately, that feature is not compatible with Powerwalls. You would need to use Enphase home batteries in a separate system. Powerwalls form and control the island grid when utility power goes down so iQ8 can't have the control to enable Sunlight backup. Since you already have SolarEdge/Powerwalls I still don't see what iQ8's add since the Powerwalls should already enable the SolarEdge to continue to produce power during grid outages

So, that's the "Sunlight backup" feature of iQ8. Unfortunately, that feature is not compatible with Powerwalls. You would need to use Enphase home batteries in a separate system. Powerwalls form and control the island grid when utility power goes down so iQ8 can't have the control to enable Sunlight backup. Since you already have SolarEdge/Powerwalls I still don't see what iQ8's add since the Powerwalls should already enable the SolarEdge to continue to produce power during grid outages.

My understanding is when the Grid is down my solar panels stop feeding the battery. So an outage of 3 or 4 days and my system is dead.

 

[Rootcanal1]

Solar Edge takes DC power from your panels and converts them to AC in the big box on your wall.

Enphase IQ8 are “microinverters”, they convert DC to AC at the solar panel. The big beige box just controls and configures the microinverters.

You certainly cannot add IQ8s to the Solar Edge directly. But, you should be able to put an entirely separate Enphase system next to it, as long as you have enough wall, roof, conduit space, etc…

Is it possible from me to have my SolarEdge that is connected to 2 powerwall have the Enphase integrated to help charge it during a power outage?

 

[RKCRLR]

My understanding is when the Grid is down my solar panels stop feeding the battery. So an outage of 3 or 4 days and my system is dead.

I have an Enphase system (IQ7 as I remember), an old string system, and 3 Powerwalls. They all work concurrently (both systems charge the 3 Powerwalls) and when my power goes out they start generating power once my Powerwall capacity has dropped to about 95%.

 

[cali8484]

My understanding is when the Grid is down my solar panels stop feeding the battery. So an outage of 3 or 4 days and my system is dead.

Assuming there is enough sunlight, your SolarEdge system should charge the Powerwalls.

 

[lodar]

My understanding is when the Grid is down my solar panels stop feeding the battery. So an outage of 3 or 4 days and my system is dead.

Wait what?!?!

It is true that Solar Panels need a “reference 60 Hz signal” to work. On a solar-only system, once the power goes out, so does the 60 Hz and the solar will shutdown.

BUT… you have Powerwalls! They will pretend to be the grid and take over the 60 Hz. The Solar Edge system wouldn’t even know there was an outage!

so I can (island) charge my batteries or home when the grid goes down.

So, this belief of yours that the Solar Edge cannot charge the Powerwalls. Is that “theoretical”? Or were the Powerwalls installed isolated from the Solar Edge?

 

[jjrandorin]

My understanding is when the Grid is down my solar panels stop feeding the battery.

Why is this your understanding? Its not the way it works in any other powerwall installion (in general terms). In slightly more specific terms, in a regular powerwall + solar installation (vendor agnostic), the solar will turn off and stop charging the batteries WHEN THE BATTERIES ARE FULL, but solar will charge the batteries before that. Its one of the main points of having solar + powerwalls.

Before spending any additional money, you should get to the root cause of why you think this is happening the way you describe it, and if it actually IS happening that way, getting whomever installed it back out to correct it.

 

[WidowMaker03TX]

So, that's the "Sunlight backup" feature of iQ8. Unfortunately, that feature is not compatible with Powerwalls. You would need to use Enphase home batteries in a separate system. Powerwalls form and control the island grid when utility power goes down so iQ8 can't have the control to enable Sunlight backup. Since you already have SolarEdge/Powerwalls I still don't see what iQ8's add since the Powerwalls should already enable the SolarEdge to continue to produce power during grid outages.

I have the Sunlight backup and I was looking at Powerwalls.

 

[cali8484]

I have the Sunlight backup and I was looking at Powerwalls.

Just to clear, the iQ8's will still work as regular grid-tied inverters with Powerwalls. There is no real need for Sunlight backup when you have home batteries.