How much fuel does a car consume when running only the air conditioner for one hour?
2 Answers
Running only the air conditioner in a car for one hour consumes 7-8 units of fuel. Here are some precautions regarding the use of car air conditioners: Choose the appropriate fan speed: During normal operation of the car, to prevent excessive frosting of the evaporator and ensure the proper functioning of the air conditioning system, the air supply speed and temperature control should not be set to the minimum for extended periods. When the vehicle speed is below 25km/h, the fan speed switch should be set to the low-speed position to avoid insufficient power generation and inadequate cooling. Duration of single air conditioner use: If the interior temperature has reached a comfortable level, the air conditioner can be turned off or switched on intermittently. Prolonged use of the air conditioner can lead to excessive pressure on the condenser, causing wear and tear to the refrigeration system. Therefore, it is advisable not to use the air conditioner for too long each time.
From my experience, the fuel consumption with AC on really depends on the situation. I drive a 1.5L family car, and actual tests showed that idling with AC on for one hour in 32°C heat burns about 1.5 liters of fuel, roughly double the normal driving consumption. The most fuel-intensive moment is right after startup when the compressor runs at full capacity. Setting the temperature to the lowest and turning the fan to maximum further increases fuel usage. Last time at a service area, I specifically tested this – the fuel gauge needle dropped noticeably after one hour. Now in summer, I avoid prolonged stationary AC use, preferring to park in shade with windows down for ventilation. It's easier on both the wallet and the environment.