In many locations, sending excess solar back to the grid makes no financial sense. One solution is to buy a battery storage system and charge the batteries using solar power and then using the batteries when there is no solar. This is called load shifting and can be very effective.
For users without large home batteries, we have another solution: use excess solar to charge your electric vehicle. The key is knowing exactly how much to charge at all times and adjusting the charge rate accordingly.
Use esp32 or esp8266 to control motorized windows and expose as HomeKit (similar to ratgdo but for windows).