The 150 MPG Fallacy
The energy required to move a vehicle is the same as before. It’s a modified Saturn VUE. So the drag and weight aren’t much different from stock. If anything it weighs more due to extra batteries and the electric motor. But for the sake of discussion it’s the same car.
That means it takes the same amount of energy to physically move it from Point A to Point B. Now instead of doing it with gasoline, you’re using electricity for much of the trip.
It should be acknowledged how much net energy is consumed during driving. There needs to be a way to equate total energy consumed for distance traveled. The reason is that a PHEV (Plug-In Hybrid Electric Vehicle) is often recharged by plugging it into an outlet, and the electricity is coming from somewhere. A 150 mpg figure is misleading for PHEVs. It makes for great headlines but it isn’t real.
It’s analogous to saying you got by last week by eating only 2 hamburgers (i.e. gasoline) and neglecting to mention the 20 helpings of spaghetti (i.e. electricity) you also ate to get through the week. If you use energy from sources additional to the gasoline in a car’s tank, it should be included in the fuel economy calculation.
Finally, it is important to recognize that the true significance here is not that the car get’s better mileage or not. It’s the fact that it offers a way to wean ourselves off of oil because electricity can come from many different sources.