I had not refuelled in over 6 weeks so I decided to freshen my fuel tank while the price cycle was at its lowest. I still showed two thirds of a tank on the gauge. I squeezed 17 litres in to maximum tank capacity. The last refill was at 1850km on July 9. The car is now 4400km. So that's 2550km driven at an effective petrol consumption of 0.68L/100km. At off peak charging rates of 10c/kwh and 50km effective range per 12kwh charge the gross cost is $83.56 ($63.20 electricity and $22.36 premium petrol incl 4c/l fuel discount of 68 cents). The fuel discount is of little value given lower fuel consumption and much longer gaps between refuelling.