How much does fuel consumption increase when idling with air conditioning on for one hour?

[DeHarrison]

Idling with air conditioning on for one hour increases fuel consumption by 1-2L. The reason is that when the air conditioning is turned on in summer, the air conditioning compressor needs to work to cool. The air conditioning compressor cannot work on its own; it relies on the engine to drive it, which consumes part of the engine's power. This is why using air conditioning for cooling affects fuel consumption. Hazards of idling with air conditioning on: 1. It causes some damage to the car: The impact is not too significant, and the car won't break down, but it does cause some wear and tear on the engine, possibly shortening the maintenance cycle (such as oil changes and other upkeep). 2. High fuel consumption: Avoid idling with air conditioning on for extended periods. Prolonged use of air conditioning with the system in recirculation mode will gradually lead to poor air quality inside the car, with increasing levels of harmful gases (carbon monoxide, nitrogen oxides, etc.), which can endanger health and even life safety.

[MacJulia]

Over many years of driving, I often encounter situations where I need to park and turn on the air conditioning. I remember the last time I was on a business trip and rested in a service area with the AC on for an hour, the fuel gauge showed a drop of nearly 1.2 liters. Generally, idling a car with the air conditioning on for an hour consumes an additional 0.5 to 2 liters of fuel, depending on the size and model of the vehicle. Smaller displacement cars, like those under 1.5 liters, might consume around 0.8 liters, while larger SUVs or diesel vehicles could reach up to 2 liters. Running the air conditioning requires the engine to operate to power the compressor, which increases the engine load. If the weather is hot and the demand is high, fuel consumption will be even greater. Doing this long-term not only wastes money but can also lead to carbon buildup in the engine and accelerate wear. Therefore, I recommend turning off the engine and opening the windows for ventilation when parked, or finding a shaded area to reduce AC usage. If you really need it, try to limit it to within 10 minutes to save fuel and protect your car.

[Julio]

As a professional who frequently deals with car issues, I understand that idling with the air conditioning on for an hour can significantly increase fuel consumption. Typically, it increases by 0.7 to 1.8 liters of gasoline, with an average of around 1.2 liters, which is directly related to the load on the air conditioning compressor. Once the compressor is activated, the engine requires additional power to drive it, naturally leading to higher fuel consumption. The actual value depends on the car's age and system efficiency, with older cars potentially consuming more. If the car idles with the air conditioning on for extended periods, the spark plugs are prone to carbon buildup, and the battery may also be overused, leading to additional maintenance costs. I always remind friends to check in advance whether the air conditioning system is optimized and, if necessary, to run only the fan at a lower setting. Avoid frequent operations, and choose shaded areas under trees or in garages when parked to save trouble.

[LeJade]

As a practicality-focused car user, I tested idling with AC on for an hour and burned an extra 0.9 liters of fuel. The difference between models is significant – compact gasoline cars consume around 0.6 liters, while larger vehicles may reach 1.5 liters. With AC running, the engine must work to power it, and the compressor's operation is the main fuel-consuming factor. Don't underestimate these numbers – prolonged idling can waste considerable money. In daily driving, I adopt smart practices like opening windows first to vent heat, then briefly activating AC for rapid cooling before turning it off. If AC idling is unavoidable, I recommend limiting it to 20 minutes. This approach reduces both fuel consumption and environmental impact.

[LeviLee]

From my research perspective, it's common for idling with AC on to increase fuel consumption by 0.6 to 2 liters per hour. While engine idling itself consumes relatively little fuel, activating the AC compressor causes a surge in demand, burning more gasoline to compensate for power output. Small cars typically see an increase of around 0.8 liters, while models with more efficient variable-frequency AC systems save some fuel. Continuous operation raises internal engine temperatures, potentially leading to issues like overheating or wear. Vehicles with start-stop systems can reduce some of this loss. Overall, it's recommended to prioritize turning off the engine during prolonged stops and maintain cabin ventilation to reduce AC dependence.