The question of whether to use air conditioning in a car or drive with the windows open consumes less fuel does not yet have an official answer. It is claimed that there is no single answer to this question; because there are many different parameters such as vehicle model, technology, design, air conditioning characteristics, driving techniques, driving information, window opening.
If over 72 km …
Here is an opinion from Chip magazine compiled by the Telegraph:
“It really depends on how fast you are going. The Society of Automotive Engineers in the United States has studied the economic impact of driving with the windows open and the air conditioner on. Below 72km (45mph), it has found that keeping the windows open consumes less fuel than the air conditioner. ”
The Telegraph says that above this speed, using the windows open will consume more fuel than the air conditioner.
“Increase of 10%”
According to British car company AA, turning on the air conditioners in vehicles increases gasoline consumption by 10%. When the air conditioner is first turned on, it works very hard to reduce the temperature inside the vehicle and thus consumes more fuel. However, when the window is opened, the aircraft coming from outside slows down, the driver presses the throttle to keep the speed level constant, and the engine runs harder. Therefore, more fuel is wasted.
Speed should be decided
In the news it is recommended to decide based on the speed traveled when you are between two options. In other words, if you are in the city, it may be cheaper to open a window if you are going slow, and to use the air conditioner if you are going faster than 50 miles.
UK-based RAC Automotive Services commented: “Open windows increase friction, slowing the vehicle and increasing the amount of fuel needed to run. Turning on the air conditioner places an additional load on the engine and requires more fuel.
As with many things, different studies tell us different things. In 2004, General Motors worked to eradicate the problem and found a trend to reduce fuel consumption in vehicles using the A / C-off approach with the windows open. But as discussed below, an inactive air conditioning system is unhealthy, and even if fuel consumption is lower with the windows open, does that air really reach the chill of reliable air conditioning? In summary, it is useful to keep the air conditioner running at frequent intervals.
“It should be used correctly at the right time”
The debate over whether it is more fuel efficient to drive with the windows open or with the air conditioner as old as daytime air conditioners were invented. When the windows are open, they reduce driving aerodynamics and increase drag, which slows down the car. However, the AC drive puts more load on the motor. Either way, your vehicle will need more fuel to run. The trick is figuring out when to use which option and using them correctly. The best time to drive with the windows open is on city and suburban streets. Conversely, the best time to drive with air conditioning is on motorways. Lowering the windows at such high speeds on the highway reduces the aerodynamics of your vehicle. While driving with the air conditioner on puts a strain on the engine, it does not affect fuel efficiency as much as driving with the windows open.
General consensus in several sources; If you drive at low speed, open the window and if you drive at high speed, use the air conditioner. However, most of the comments are based on a 2004 study.