What is the most fuel-efficient temperature for car air conditioning in summer?

[LaVivian]

In summer, setting the car air conditioning to around 26℃ is generally more fuel-efficient. The comfortable temperature range for the human body is between 24℃ and 27℃. Additionally, it's important to consider the local weather temperature, and the temperature difference between the inside and outside of the car should not exceed 5℃. According to thermodynamic principles, the energy consumption of the air conditioning is only related to the temperature difference, the size of the car's interior space, and the sealing of the space. Using the recirculation mode in summer is more fuel-efficient and provides the best cooling effect. More information about car air conditioning is as follows: Recirculation and Fresh Air Mode: Recirculation mode means the air inside the vehicle is recirculated, i.e., the air coming out of the vents is from inside the cabin, and the cabin is sealed off from the outside atmosphere. Fresh Air mode means outside air is drawn into the cabin, i.e., the air coming out of the vents is from outside the vehicle, and the cabin is open to the outside atmosphere, not sealed. Advantages and Disadvantages: Recirculation mode means the air blown by the blower circulates inside the car. Since no outside air is involved, it has the advantages of being fuel-efficient and cooling (or heating) quickly, but the disadvantage is that it is not conducive to updating the air inside the car. Fresh Air mode means the blower draws fresh air from outside into the car. The advantage is that it ensures air quality inside the car, but the cooling (or heating) is slightly slower, and it also consumes more fuel.

[DelJayce]

In summer, setting the car AC around 25°C is most fuel-efficient. If set too low like 18°C, the compressor has to work harder, significantly increasing fuel consumption. I remember during a long trip, setting the temperature too low made the fuel gauge drop rapidly, but adjusting to 25°C improved it. I usually use recirculation mode to reduce hot air intake, easing the AC's workload. When it's hot outside, avoid setting too big a temperature difference – for example, 25°C is ideal when it's 35°C outside. Cars with automatic AC are more convenient; just press AUTO for optimal airflow and temperature. Regular maintenance matters too – a dirty cabin air filter reduces efficiency and increases fuel consumption. Smooth acceleration also helps save fuel; avoid sudden acceleration and braking. Find a balance between comfort and fuel efficiency.

[MacGabriela]

I've researched car air conditioning systems. The compressor is driven by the engine, and higher loads lead to increased fuel consumption. Setting the temperature between 24-26°C is most fuel-efficient because the compressor won't operate at full speed. When set too low, the cooling system works continuously under high load, increasing fuel consumption by over 10%. The recirculation function is crucial as it cools quickly and maintains temperature, reducing energy use. For maintenance, replace the cabin air filter annually, and system refrigerant leaks also increase fuel consumption. With automatic climate control, it intelligently adjusts fan speed after setting the temperature. In city driving, avoid sudden acceleration as smooth starts save fuel. Temperatures too high are uncomfortable - around 24°C balances comfort and economy.

[SanLaila]

I prioritize environmental protection while driving, setting the air conditioning temperature higher to save fuel and reduce emissions. In summer, setting it above 26°C reduces compressor operation, lowering fuel consumption and carbon emissions. A smaller temperature difference, like setting it at 26°C when it's 30°C outside, can save a lot of fuel. Using recirculation mode more often helps cool the car quickly and maintain the temperature. Get used to not pursuing excessive cooling; adapting to slightly higher temperatures benefits the planet. Regularly check the air conditioning system to ensure efficient operation. Saving fuel not only saves money but also protects the environment.