First time Towing and Terrible MPG - PowerBoost

[JohnTrigger]

Keep in mind that wind resistance goes up as a cubic function. So when you go from 30 mph to 60 mph the wind drag goes up by a factor of 8.

Drag is proportional to velocity squared, so doubling the velocity makes the drag go up by a factor of 4.

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[FaaWrenchBndr]

Also driving 70-75 I doubt tow mode was used.
This would have the boost kicking in quite a bit. That would certainly explain the extremely low mileage.

 

[Gros Ventre]

Drag is proportional to velocity squared, so doubling the velocity makes the drag go up by a factor of 4.

While it's true that drag goes up by a square function... the power then required to double speed is a cubic function. Consider: Under the assumption that the fluid is not moving relative to the currently used reference system, the power required to overcome the aerodynamic drag is given by:

The power needed to push an object through a fluid increases as the cube of the velocity increases. For example, a car cruising on a highway at 50 mph (80 km/h) may require only 10 horsepower (7.5 kW) to overcome aerodynamic drag, but that same car at 100 mph (160 km/h) requires 80 hp (60 kW).[18] With a doubling of speeds, the drag/force quadruples per the formula. Exerting 4 times the force over a fixed distance produces 4 times as much work. At twice the speed, the work (resulting in displacement over a fixed distance) is done twice as fast. Since power is the rate of doing work, 4 times the work done in half the time requires 8 times the power.

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