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Battery Control

Your home battery is good at managing itself. Franzl only steps in where it genuinely knows better, and tells you when that is.

The principle: only step in for a good reason

Modern storage systems have their own energy management that fine-tunes self-consumption, more finely than any external system checking in once an hour ever could. Franzl respects that: in normal operation, it sends no commands to the battery at all, and says so plainly ("Managing itself, self-consumption").

Franzl steps in only where coordination adds real value:

The battery in the queue

When there's solar surplus, the car, the water heater, and the storage system all compete for the same kilowatt-hours. Franzl distributes the surplus in your order and can deliberately move the battery up or down the queue: "Battery first, up to 80%" means the storage system gets priority until it has its reserve. After that, the full surplus goes to the car, and the battery tops up the rest once the car is taken care of. A practical side effect: the battery doesn't need to be commanded at all for this; its own management automatically follows whatever's left over.

Arbitrage: for storage systems that can do it

With a dynamic tariff, actively shifting energy can pay off: charge cheaply from the grid, supply the house at the price peak. That requires your storage system to actually execute grid charging on command, and by no means all of them can. Franzl only offers arbitrage for brands whose control path has proven it can do this; for everyone else, the option simply isn't shown, rather than sending commands into the void. The model-by-model status is in the device database.

Honesty in the numbers

Battery savings are easily double-counted (once on charging, once on discharging). Franzl credits the value exactly once, on discharge, as the difference between the current price and the charging cost. And the state of charge comes from the device itself: if it's unknown, the app shows a dash, not "0%".