Here is the formula I came up with for my comparisons:
eMPG= =G$/(E$/(1000/Whr/M))*(Eff/100)
G$ = cost of gas per gallon in dollars
E$= cost of KWhr of electricity in dollars
Whr/M= Watt hours used per mile (from car)
Eff= Charging efficiency (percentage)
Here in Sacramento CA, gas is 4$ per gallon, my electricity is .06$ per KWhr, my Whr/m is 333 and I am guessing the charging efficiency is 85%
This gives me and eMPG of 170 miles per 4$ gallon. Much cheaper than a Prius! :smile:
If anyone has a better number for charging efficiency, let me know. I like the 85% because for an 85 KW battery, it works out the the cost for a complete charge is 100X your KWhr electricity cost, or 6$ for me. Of course that number is pretty meaningless but it is something to throw out to the Prius owners...