This must have come up in the past but I can't find it. Does someone know if there is a formula that equates kilowatt hrs. per galon of gasoline when running the Clarity in HV Charge mode? Sometimes when I am on a longer trip electricity can be pretty expensive on the road. I wonder sometimes when I have time to plug in but power is going for 35 to 50 cents per Kw/hr, I wonder if I am just better off using $4/gallon gasoline. TIA.