Does Using Car AC Consume More Fuel?
2 Answers
Using the car air conditioning does consume more fuel. Here is relevant information about vehicle air conditioning systems: 1. Concept: The vehicle air conditioning system consists of a compressor, condenser, throttle element, evaporator, fan, and necessary control components, designed to regulate cabin temperature and humidity to provide a comfortable environment for occupants. The refrigerant continuously circulates through the system, with each cycle including four processes: compression, condensation, throttling, and evaporation. 2. Working Principle: When the compressor operates, it draws in low-temperature, low-pressure gaseous refrigerant from the evaporator. After compression, the refrigerant's temperature and pressure increase, and it is then sent to the condenser.
I specifically tested it on a long-distance trip last time, and turning on the AC does consume more fuel. The AC compressor is driven by the engine, which means the engine has to work harder. My 1.6L car burns about 1.5 liters more per 100 km in the city with the AC on, and around 0.8 liters more on the highway. The lower the temperature setting, the more fuel it consumes. In summer, when set to the coldest, the compressor almost never stops running. However, never roll down the windows to save fuel—at speeds over 60 km/h, the increased wind resistance from open windows consumes more fuel than the AC. It's recommended to ventilate the car by opening the doors first if it's been sitting in the sun, then turn on the AC and set it to around 25°C for the most economical use.
