How much does using car air conditioning affect fuel consumption?

[DeEverly]

Difference is 20%. The car air conditioning system consumes about 20% of the engine's power, so using AC will utilize a portion of the engine's power, leading to increased fuel consumption. The exact increase in fuel consumption depends on the vehicle's displacement and speed. Here's relevant information: 1. Specific fuel consumption: For a car that normally consumes 10 liters per 100 kilometers, using AC will increase fuel consumption by approximately 2 liters. The impact of AC on fuel consumption is very noticeable, while different fan speeds have relatively smaller effects. 2. Principle of increased consumption: The car engine actually powers the AC compressor, so when the cooling AC is turned on, the engine experiences increased pressure and requires more gasoline to burn for power. This explains why sometimes when driving with cooling AC on, the car's power feels slightly weaker - because the engine is under increased pressure.