Document how to do advanced battery usage

[xperseguers]

This is a suggestion to enhance the documentation or possibly get pointers where it's documented already but I missed it.

When I read the official documentation (https://github.com/WillCodeForCats/solaredge-modbus-multi/wiki/Configuration) there is virtually not any real explanation on what Power Control options would do when enabled.

I did not enable it (yet) because I have no time to investigate right now and the warning message is scary enough :)

Describe the feature

When having batteries, and with Fall and Winter coming, there is less and less solar activity and some days sun is not sufficient to fully recharge the batteries during the day.

In Switzerland I have a double tarification for buying energy from the grid. In short it's cheaper over night than during the day. It will change in 2026 with some lower rate around noon but the idea is there. I already have a template sensor for knowing how much the energy from the grid costs at the moment.

It looks like it could be interesting to force charge the battery out of the grid during the night to consume during the day if there won't be enough sun during the day. That's the basic idea.

Based on this discussion in HA community (https://community.home-assistant.io/t/enough-solar-energy-later-to-charge-battery/592671/8), it looks like EMHASS plugin could be interesting to figure out if it would be worth it charging from the grid.

What I miss im the documentation (by reading, as said possibly it's more clear by just trying out), is whether enabling Power Control (and possibly "Storage control"?) is what will ultimately be needed to force the battery to charge, say at 5.30 AM and switch back to, say, "maximize efficiency" when done or when higher tarif starts.

So my request would be to possibly have some more description in the documentation, possibly with external pointers if one wants to go that way. I suspect you are doing something like that as maintainer for your own installation, so having some feedback or suggestions in the doc would be awesome.

Home Assistant

• Home Assistant Core Version: 2025.10.1
• solaredge-modbus-multi Version: 3.1.7

[WillCodeForCats]

The reason is because I don't personally have batteries and my inverters don't accept commands over modbus.

So that part of the documentatuon is either contributed, stuff I've read, or just what other docs say instead of me having direct experience with it.

Contributions are welcome.

[apf-doit]

@xperseguers yeah, those settings scare me too, but i think the only way to find out is try out. I am on the lucky side having a SE backup power interface which gives me the opportunity to distinguish between "emergency supply" (Notsrom) and "replacement power supply" (Ersatzstrom). In that case I can control battery charging with a slider called "backup reserve" - not sure if this is a default endpoint or will just be available when the inverter knows there is a backup power interface.

So, whenever i have solar power available the battery get charged until full capacity and then the inverter starts exporting whatever is left after internal usage. When solar is off and power is supplied by battery that slider controls when to stop to supply to keep that reserve for the inverter when the grid goes off (power outage), usually I keep 5-10%. The cool thing now is: the same way using that backup reserve feature i can control when the battery should be charged from the grid (when the tariff is cheap). I also had to install an additional meter to let the inverter knows there are devices with high usage character like EV wallbox and heatpump. Those device where locically hidden before. Means i even can charge my EV or run the heatpump from the battery.

I am not too sure how that all works but it just works. Maybe it isn't even a feature, but without that specific backup device I could not control as much as I can now. With a few automations I can easy setup a nice balanced workflow depending on solar and tariff costs (i have a dynamic tariff with 15min intervall price changes).

The only thing I haven't figure out yet is: my inverter limits the import from the grid down to 1kW while when solar power comes in it charges with the max. 5kW. That's why I am still interested in that topic you have created to find out how to eliminate that specific limit. Here is what AI is suggesting:

• Does the inverter + battery support “Charge from AC / Grid”? check
• In inverter/web UI: enable Advanced Power Control / Set Reactive Power mode to RRCR (if required) not checked yet
• In inverter/web UI: set Storage Control Mode to Remote (or similar) not checked yet
• In inverter/web UI: set Storage AC Charge Policy to “Always Allowed” (or equivalent) check
• In Home Assistant: set number.solaredge_storage_ac_charge_limit to desired value (e.g., 5000 W) not checked yet (slider grayed out)
• In Home Assistant: set control mode to “Charge from PV + AC” (or “AC + Grid”) via select.solaredge_storage_control_mode not checked yet

Maybe it helps you too in some way.

cheers
Alex