Grid Tied - store excess solar using EG4 6000xp to batteries

[slypig]

Goal: Collect as much solar as I can to batteries, not send to the grid.

System:
I built a ground mounted solar system in 2017 with the help of a friend.

24x Panels Max. output about 254watts
12 Micro Inverters (APsystems YC500)
Max. output is about 6096 watts
Max. kWh per day around 49
Power Lines to the house (160ft underground) to power company meter, then a 50amp breaker to the main.
Main meter runs backwards when I'm creating more power than using.

Local power told me I was on net metering, 1 credit in 1 credit out. (not true)

I later found out that they switched it before I was connected to a different kind of net metering, they pay me a certain amount for the solar and charge me whatever they have at that time for buying it back.. no net metering as I was told. I might fight them but it's a losing battle.

Anyway, I want to install backup batteries.

I like the look of the EG4 6000xp and then the EG4 PowerPro (to hold as much as I can each day and use in the house, charge cars)

I want to take the solar, that I would otherwise be sending back to the grid, and charge batteries with it.

I assume that I'd need some CTs to measure what the solar is being produced or what is going to the grid and then feed that info to an inverter to know how much to pull from the "grid" and charge the batteries.

I just don't know where to start with my goal in mind. Not send solar power to the grid without changing the current wired setup. I want to leave that how it is and take the excess power to batteries.

 

[BentleyJ]

The EG4 6000XP is an off-grid inverter. It does not have the capability to AC couple with the present micro-inverter system but it could still be used if you are willing to do the following. Install a critical loads subpanel that is powered by a 6000XP and move some of the breakers into the new subpanel. Micro-inverters would have to stay connected to the main panel and would shut down in the event of a grid outage. The batteries would be charged by excess solar using a stand alone charger. Not sure if there are any stand alone chargers that have the capability of being controlled by PLC or Modbus using CT's and battery state of charge parameters.

In order to accomplish your stated goal of using CT's to measure solar production and modulate charging such that it captures as much as possible is going to require an inverter that is capable of being controlled externally. Schneider XW Pro is the only inverter I know of that has a full featured Modbus interface that can be controlled by a Programmable Logic Controller or Node-Red.

I would recommend looking up previous content on this forum by GXMnow who has done essentially what you are describing with a Nano-10.

Also, n2aws and 400bird have posted excellent info on using Node-Red to interface with Schneider InsightHome via Modbus TCP.

Using the info they posted I've been able to get Node-Red working and I'm barely literate as a novice computer/software guy.

 

[slypig]

The EG4 6000XP is an off-grid inverter. It does not have the capability to AC couple with the present micro-inverter system but it could still be used if you are willing to do the following. Install a critical loads subpanel that is powered by a 6000XP and move some of the breakers into the new subpanel. Micro-inverters would have to stay connected to the main panel and would shut down in the event of a grid outage. The batteries would be charged by excess solar using a stand alone charger. Not sure if there are any stand alone chargers that have the capability of being controlled by PLC or Modbus using CT's and battery state of charge parameters.

In order to accomplish your stated goal of using CT's to measure solar production and modulate charging such that it captures as much as possible is going to require an inverter that is capable of being controlled externally. Schneider XW Pro is the only inverter I know of that has a full featured Modbus interface that can be controlled by a Programmable Logic Controller or Node-Red.

I would recommend looking up previous content on this forum by GXMnow who has done essentially what you are describing with a Nano-10.

Also, n2aws and 400bird have posted excellent info on using Node-Red to interface with Schneider InsightHome via Modbus TCP.

Using the info they posted I've been able to get Node-Red working and I'm barely literate as a novice computer/software guy.

Thank you. I reached out to 'Signature Solar' and they used words that I'd not understood before, like 'AC Coupling' and your response is very helpful too. I'll look around now with this newfound, though limited, knowledge and see what I can discover.

I like how the EG3 6000xp shows in all the videos that I've seen of them. It's simplicity has me very interested. I like your idea of setting up a Critical loads subpanel as that was what I was thinking would the path to get me started as I moved my circuits in the home over from the main panel to one that runs from the batteries.

Maybe I can investigate some sort of automation that switches on the Grid power to the inverter to charge the batteries once the solar created gets above the 5500watts, but that would leave a lot of power at the beginning and end of the day going to waste.

I'll see what I can find posted from GXMnow, n2aws and 400bird to see what I can learn.

Many thanks!

 

[slypig]

As I learn more, I'm thinking that if I want to stick to simplicity, and want the features I should be consider the Sol Ark 15k. Costs a lot more but would give me those features that I'm looking for.

I continue on.