How much fuel does a car consume when running only the AC without moving for one hour?

[LeMaximus]

Running only the AC without moving consumes 2.5L of fuel per hour. Below are the impacts of running the AC while the car is stationary: 1. Battery: While the AC compressor is indeed driven by the engine, the blower fan is powered by the battery. When the car is idling, it may not necessarily charge the battery. Excessive use of the blower fan can drain the battery, leading to long-term battery depletion. Driving at high speeds occasionally can help recharge the battery and maintain its health. 2. Engine: Without the AC, the air blown out utilizes waste heat from the engine, which is the principle behind the car's heating system in winter and does not involve the AC refrigerant. A handy tip: If the car's coolant temperature remains too high, indicating insufficient cooling from the front radiator fan, turning on the heating system can provide an additional cooling channel as an emergency measure. 3. Long-term effects: Prolonged idling with the AC on increases fuel consumption and engine carbon buildup, with the greatest harm being to human health. In a stationary state, the air inside the car does not circulate properly. Keeping the windows closed can lead to a false sense of comfort, causing occupants to fall asleep unknowingly, risking carbon monoxide poisoning or oxygen deprivation.

[Zoey]

I have a habit of tinkering with cars in the garage and found that idling with the AC on for an hour does consume quite a bit of fuel, roughly fluctuating between 0.5 to 2 liters, depending on the engine displacement and AC settings. I personally tested my compact car with a 1.6L engine—during summer at max AC setting, it burned nearly 1 liter of fuel per hour because the engine had to keep running to power the compressor. For larger-displacement SUVs, fuel consumption is even higher, possibly exceeding 1.5 liters. Doing this long-term not only spikes fuel costs quickly but also leads to carbon buildup in the engine, affecting its lifespan. It’s advisable to avoid prolonged idling; for instance, turn off the engine while waiting roadside to save money, and regularly check AC efficiency during maintenance.

[SanLucille]

As a car mechanic with over a decade of experience, I've encountered countless similar cases. The most reliable estimate for fuel consumption when idling with AC on for one hour is 0.5-1.8 liters, depending on the vehicle model and year. The compressor requires engine power, which burns gasoline during power transmission. I've serviced Toyota Corollas that consume about 0.7 liters per hour with AC on, while older American models can reach up to 1.5 liters. Remember to check your engine condition - older vehicles consume more fuel, and dirty AC filters increase the load. Develop good habits: turn off the engine if waiting at red lights for more than 2 minutes. Don't think these small amounts of fuel are insignificant - they add up and can really hurt your wallet.

[AdalineRose]

I often encounter traffic jams during my daily commute, and I've estimated that idling with the air conditioning on for an hour consumes roughly 0.6 to 1.2 liters of gasoline. For example, with my Honda Fit, last summer I tested it—running the AC at medium fan speed for an hour noticeably dropped the fuel gauge, about 0.8 liters. Many factors affect this, such as the car's age and the weather. In winter, using the heater consumes slightly less fuel. This habit isn't recommended—not only does it waste fuel and pollute, but the engine might also overheat and stall. For daily driving, it's better to opt for ventilation to save fuel. If you really need AC, it's more efficient to turn it on after the car is moving.

[LeCorey]

I have been concerned about environmental protection for many years. Idling with the air conditioning on for one hour actually consumes a considerable amount of fuel, typically 0.7 to 1.6 liters of gasoline. This not only wastes resources but also increases carbon dioxide emissions, polluting the air. Taking a small family car as an example, burning about 1 liter of fuel per hour can emit approximately 2.4 kilograms of carbon. Many people in big cities doing this exacerbates smog. I urge everyone to avoid such wasteful behavior. When turning on the air conditioning, keep it short for handling tasks. For long stops, open the windows or simply turn off the engine. Maintaining your vehicle can also reduce energy consumption. For instance, regularly cleaning the air conditioning system can save 5% on fuel consumption.