You can use a single Switch - one input mutilple outputs - to save some nodes.
The core of my flow looks like this:
I use two triggers in series as a filter to ensure that the incoming level remains high enough (or low enough) for a period but allows peaks and troughs without switching the relay too many times:
Which says “Once the solar reaches threshold, send 1s and but allow it to drop for at least one minute before sending a 0; then wait for it to remain high for at least 5 minutes before turning power on”.
Conversely, the “off” side has an identical first switch component but the second send a 0 (instead of a 1) after 15 minutes of “low” solar.
I’m still hacking at the “Adaptive Amps” function as I don’t like the way it oscillates just over the total solar leading to a little exporting. More on that soon.