As simple and easy as I know how to explain it
EV: Electric only, good for short trips around town within the range of your battery charge
HV: Regular hybrid vehicle mode, in general the gas engine will start and stop as needed to try and maintain the charge level you started with. Sometimes it will start in order to charge the 12v battery
HV/Charge: Mostly useful when on a trip. If your battery gauge is low, HV/Charge can restore up to about 60% of battery capacity.
Will not restore 100% that way. May use slightly more gas than HV mode as gas engine may run longer/faster to operate generator
Sport: Use only when your EGO is low.
May or may not restore that. I never use it, idea of car is to use less gas, not more :surprise:
I can't figure out when to use HV Charge. Have you seen any gains in efficiency by using HV Charge to sacrifice gas mileage in order to drive around on EV at a later time? I haven't done enough testing, but so far it seems like losing MPG to gain a little electric later in my drive is a net loss. I would love to be wrong about this, though!