Originally Posted by Double-Trinity

Also, reporting that air-conditioning costs 1mpg in an SUV, and 6mpg in a hybrid suggests the air conditioning is less efficient in the hybrid, when in reality they both burn about the same amount per hour to cool the same amount of space. Report air-conditioner consumption, and other accessory loads in gallons per hour makes sense, as those things are not at all related to distance covered or speed. It's also a lot easier to compute the actual cost that way.