Minka havenworth fan with tx and rx
Green/Yellow is always ground

Green/Yellow so happens to be the international color code for protective earthing (grounding) wires; as thus, the NEC designates it as reserved for that purpose, too, even more so than plain green wire is!

So, connect the green/yellow wire to the ground wire, and cap the red wire off.  Also, make sure there's a wall-switch-controlled light somewhere in the room!