I have a MultiPlus installation connected to AC-in and I use ESS to minimize grid consumption. Everything works fine, but there’s one issue: when charging my car at night or during poor weather, the ESS battery gets drained.
What I’d prefer is for this additional load (the car) to be supplied fully—or at least partially (depending on a setting)—directly from the grid.
The hybrid car is connected to a Tasmota power meter, which I’ve already added via DBUS programming as an EV device in my Venus system (see screenshot, currently showing 0 W).
Question: How can I ensure that the entire charging load of the car comes from the grid?
My only idea so far is to temporarily adjust the ESS target by the power draw of the EV device.
For example:
If the ESS target is set to -50 W and the car is currently drawing 2000 W, then I’d increase the ESS target by +1950 W.
That way, the car wouldn’t pull from the battery.
If I wanted only 25% of the charging power to come from the ESS battery, I could increase the target by +450 W (25% of 2000 W).
Unfortunately, I can’t control the car’s charging power—it’s either ON (2000 W) or OFF.
What about having a winter setting? If turned on and car is actively charging, set the Inverter to “charge only” mode. I know you then use the grid for powering both car and house during charging, but I guess this is not an issue, since you expect to charge car during the cheapest hours.
I need at least this “winter” mode and weird that not many other needs this. I dont want to rewiring te charge station before/after my smart-meter every time we shift winter-summer or summer-winter. I dont know what happens in VRM if this was done with a manual switch?