How much fuel is consumed by idling with the air conditioning on for one hour?
2 Answers
Idling with the air conditioning on for one hour consumes 1-2L more fuel than driving normally without the air conditioning. In summer, when the air conditioning is turned on, the compressor needs to work to provide cooling. The air conditioning compressor cannot operate on its own; it relies on the engine to drive it, which consumes some of the engine's power. This is why using air conditioning for cooling affects fuel consumption. Here are some methods to save fuel when using the air conditioning: 1. If the car is parked outdoors in summer: It's best to open the windows before turning on the air conditioning. Avoid immediately turning on the cooling function; instead, set the fan to maximum speed to accelerate ventilation and wait for the hot air inside the car to dissipate before turning on the cooling. 2. Adjust the air vents: Pointing the vents upward improves cooling efficiency through physical principles. 3. Avoid setting the air conditioning temperature to the lowest for extended periods: A large temperature difference between the inside and outside of the car can increase fuel consumption and also affect the health of the passengers.
I once tested the idling fuel consumption several times while waiting in my car with the AC on during summer. My sedan has a 1.6L engine, and running the AC consumed about 1.3 liters of gasoline per hour. If it were an SUV, it might go up to around 2 liters, depending on the vehicle size and AC temperature setting—setting it too low would consume even more fuel. I recommend avoiding this practice because prolonged idling can cause carbon buildup in the engine, which is troublesome to clean and affects the car's lifespan. It's better to turn off the engine, roll down the windows for ventilation—saving fuel and being eco-friendly—or park in the shade with a small fan running. In short, burning 10-15 yuan worth of fuel per hour isn’t worth it. Developing good habits is what matters most.
