Does Starting the Car with AC On Consume More Fuel?
3 Answers
Using the air conditioning while driving does consume more fuel. Here are some explanations regarding fuel consumption with AC on while driving: 1. Reason for Increased Fuel Consumption: High usage rate of the car's air conditioning. To reduce the fuel consumption caused by the car's air conditioning and lower the actual fuel consumption of the vehicle. Setting the car's air conditioning to the lowest temperature. In this case, the AC compressor will keep running, and the blower will remain at a high fan speed, which can actually increase fuel consumption. 2. Ways to Reduce Fuel Consumption: The correct method is to lower the windows immediately after entering a car that has been exposed to the sun. Do not turn on the AC right away; wait for one or two minutes until the temperature inside and outside the car balances. Then, close the windows and turn on the AC, making sure to set the AC circulation to the indoor circulation mode.
After driving for so many years, I can confidently say that turning on the AC after starting the car does consume more fuel. This is because the car's air conditioning compressor is driven by the engine. Once you press the A/C button, the engine has to output additional power to run it, increasing the load. This is especially noticeable at idle or low speeds. Based on my tests, fuel consumption can increase by 10% to 20%. For example, if the original fuel consumption was 8 liters per 100 kilometers, it might jump to 9.6 liters. On the highway, the impact is smaller but still significant. My suggestion is to open the windows for ventilation for a few minutes when the weather isn't too hot in summer, then close the windows and turn on the AC once the car cools down a bit. This can save fuel. Additionally, regular maintenance of the AC system, such as cleaning the filters, can also improve efficiency.
From a fuel-saving perspective, turning on the AC immediately after starting the car will definitely consume more fuel. I've tested this many times and noticed that once the AC is on, the engine noise increases while power decreases—clear signs of additional load. The principle is that the compressor consumes engine power, directly driving up fuel consumption. If you want to save money, I recommend not rushing to turn on the A/C after starting; wait until the engine stabilizes before activating the AC. Alternatively, set the temperature higher, like 25°C instead of 20°C. Also, using recirculation mode more often can reduce cooling demand and shorten AC operation time. Remember, opening windows is more cost-effective for short trips, while long journeys justify using the AC for comfort.