New charging mode: Home-battery + PV

[cschlipf]

Is your feature request related to a problem? Please describe.
Yesterday my home battery was almost fully charged, my vehicle not yet. But I knew that I had to leave in one hour. Starting then I would feed in excess energy, while my vehicle was not yet fully charged until then.

So I did the following: I set to fast charging mode and limited the charging power manually so that the vehicle was charged from excess energy and from the home battery so that the home battery could be recharged later while I am away. Unfortunately it was partially cloudy, so I had to adjust the charging power several times, which was not optimal of course.

Describe the solution you'd like
Besides the modes PV, MIN+PV, and FAST I would like to get another mode BATTERY+PV. In this mode EVCC is using energy from the PV plus the maximum power that the home battery can deliver minus the power the home consumes.

E.g. PV delivers 6kW, home battery delivers up to 5 kW while SOC of the home battery is above a certain threshold and home requires currently 1 kW then EVCC allows the wallbox to charge with 10 kW.

This might new configuration options like 'minSoc' under which EVCC does no longer use the home battery for charging and 'maxBatteryPower' which configures how much power the home battery can deliver.

Describe alternatives you've considered
Just charge in 'Fast' mode, which also drains the home battery while the PV does not deliver enough power. But this would also require additional grid energy, if the PV does not deliver enough power.

Reduce charging power constantly, but this would not consume as much energy from the home battery as available.

[VolkerK62]

passt mMn thematisch hierhin #3530

[cschlipf]

Stimmt! Genau das wird in #3530 bereits diskutiert.

[andig]

Wäre das nicht durch #7802 mindestens tw adressiert?

[andig]

Keine neue Erkenntnis, closing.

[cschlipf]

@andig - Sorry - erst heute gesehen. Nein. #7802 addressiert das nicht. Hier ist es eine persistente Einstellung. Ich hätte das gerne als temporären Charging Mode. "Baller rein was geht von PV und aus der Batterie, weil ich in 1 Std wegfahre und die Batterie danach genug Zeit hat sich wieder aufzuladen" ABER "Wenn ich zurückkomme, nehme wieder meinen default Charging Mode wie in der YAML eingegeben ("pv" bei mir)"

[andig]

Ich hätte das gerne als temporären Charging Mode.

Verstanden. Da musst Du Dir im moment mit Heimautomatisierung behelfen...

[cschlipf]

Ja... ich fände es cool, wenn EVCC das könnte ;-)

[andig]

Fürchte ich muss mir erstmal einen Akku besorgen um da mitsprechen zu können...

[KNZZZZZZZ]

Is there already a way to use this BATTERY+PV option in the mean time?
It also regularly happens to me that I want to fast charge the car in the morning without grid usage, so by PV and draining the home battery to 20% so that the home battery can charge in the afternoon when I am not at home.
Thanks!

[cschlipf]

Is there already a way to use this BATTERY+PV option in the mean time? It also regularly happens to me that I want to fast charge the car in the morning without grid usage, so by PV and draining the home battery to 20% so that the home battery can charge in the afternoon when I am not at home. Thanks!

Not yet. I plan to use Home Assistant to emulate such a mode (force discharge of battery while charging. I am hoping this will cause EVCC to automatically increase the charging power.)

[KNZZZZZZZ]

Ok, I might try that too.
But why was this topic closed? Is this specific situation perhaps already being addressed elsewhere?
Is there no interest in implementing this at evcc? This is a perfect way to charge "greener" with fewer charging losses because of fast charging instead of slow charging using the battery now in PV mode when there is not enough sun.

[cschlipf]

@KNZZZZZZZ I think @andig closed it because I didn't respond in time to his question and because there was a misunderstanding. @andig - can we re-open it?

I think the implementation would not be too hard. In this mode charging must equal to

PV Generation - Home Use + ( Battery max power - 10%) = Charging power

I am considering the 10% to have some room for power fluctations to prevent unnecessary grid consumption.

So e.g. PV is generating 7 kW, Home is taking 1 kW and Battery can deliver 5 kW:

7 kW - 1 KW + 4.5 kWh = 10.5 kW

When I do that via home automation as described above I fear that if the home automation is not fast enough or does not properly recognize the end of a charging session, I will end up with feeding in power to the grid from the battery, which is prohibited in Germany. That's why I would feel much more comfortable if that's controlled right by EVCC.