Which is more fuel-efficient, recirculating air or fresh air mode in car air conditioning?

[KimberlyMarie]

Using recirculating air mode in car air conditioning is slightly more fuel-efficient than fresh air mode, but the actual difference is minimal. The fuel consumption in fresh air mode is about 0.1 liters per 100 kilometers higher than in recirculating air mode, which is negligible. Here are the relevant details: 1. Fresh air mode introduction: Fresh air mode draws air from outside the vehicle, directs it to the air conditioning system for heating or cooling, and then blows it out through the vents. This mode replenishes fresh air and improves the air quality inside the car. However, if the outside weather is extremely dry and hot, the air conditioning compressor has to work continuously to cool the hot air from outside, consuming additional fuel. 2. Recirculating air mode introduction: Recirculating air mode circulates the air inside the car. The air conditioning system draws in the cabin air, cools it, and then returns it to the cabin. Once the cabin temperature reaches the set value, the air conditioning compressor stops working, reducing the engine load. Therefore, the faster the cabin temperature drops to the set value, the sooner the engine load decreases, leading to lower fuel consumption.