On a hot day and traveling in a car, which method of keeping the occupants comfortable with the A/C is more energy and fuel efficient?
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Set the thermostat to a lower temperature and keep fan speed to the lowest setting
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Set the thermostat to a slightly higher temperature and compensate by setting the fan to a higher speed so you can feel cool enough with the breeze
A vehicle AC compressor does cycle. There is a clutch on the pulley attached to the compressed that engages the compressor or lets the pulley free wheel.
Also the alternator absolutely takes more power from the engine in proportion to how much energy it’s putting out.
Whether it cycles based on temperature or on a fixed timer probably depends on how old/cheap your car is.
As far as I’m aware, my temperature dial is directly linked to the engine air gate and all my AC button does is turn on the compressor.
Most if not all of that comment probably applies to my car.