Eternal debate: Open the windows or use the air conditioning, what consumes the most? 7 issues to decide what is best

it Is surprising that the debate between open windows or use the air conditioning follow in the air, if you eat more the first, or the second. But in effect it is. Probably access this article waiting for a response, to defend it if it is that you have to practice it, and deny it if it is not so. If this is your case, I can assure you that this article is not for you. But the reality, as usual, makes that not everything has to be white or black, there are nuances in favor and against the different possibilities. And the only important thing in this case is to have common sense, before all of that, and be familiar with the technology that equips our car. That is why we will analyze the issue from 7 questions about the windows and the air conditioning that you have to know. The conclusions about what is best and when is the best time, you’ll have to take them off you.

In general lines and safe speeds, highway, conditioners consume more energy than the windows open. What we cannot do is to establish a general rule that says how much, in both depends a lot on the system, the use, the car that will equip…

1. The air-conditioning consumes energy. It is a truism, don’t you think? We’re not going to go into too much detail to explain the functioning of a system of air-conditioning, but enunciaremos that the cooling of the passenger compartment of our car, achieved by a team that consists of a circuit with a gas, which in turn is subjected to a series of physical changes by means of a compressor, a condenser and an evaporator. The compressor requires energy to compress the gas, energy – kinetics – which is obtained from the motor itself. That is the reason why our car is slower when you connect the air conditioning, feeling that becomes especially palpable in engine little powerful, atmospheric, low-displacement, etc.

it Is difficult to determine how much it consumes exactly an air conditioning system, because in reality depends on many factors, such as the presence of a climate control that regulates the intensity automatically, or even systems and modes as “economic” that hold the line on the consumption and the performance of the climate control. The coolers have also been the subject of many improvements in the last few years, the obsession of the manufacturers by reducing the consumption of their cars.


If the windows lowered to consume less fuel, you’ll have to decide if it’s worth it to spend the extra to enjoy driving more comfortable.

2. to Open windows consumes energy. Why? Because the aerodynamics of our car is affected. Another of the points that the manufacturers have tried to improve a lot in the last few years has been the improvement of the aerodynamics, since they make cars that – speaking in colloquial terms – “cut the wind” with greater ease, resulting in lower consumption. The mythbusters got into the mob to prove, empirically, if opening the windows uses more fuel than using the air conditioner, and at least to 45 mph (72 km/h), they found that lowering the windows consumed more fuel. Once more there are to take into account the peculiarities of the car, an employee, a big SUV, in a test that generated quite a few questions (Autoblog). Even so, to make this test a general law, especially when you consider other factors, such as pie in the city and highway, it is at least presumptuous.

two years Ago we also did echo in Tecmovia of a report (see report of the SAE) which reached a conclusion very interesting. In two vehicles as different, by their energy performance and their aerodynamics, such as a Toyota Corolla and a Ford Explorer, they found that the windows downs were more efficient than the air conditioning at speeds of up to 121 km/h and 130 km/h, respectively.

Of what we can be sure of is that the aerodynamics at low speeds, for example in the city, is not a determining factor for our consumption.

aire-acondicionado-vs-ventanillas-04-1440px3. does it really worth to win a few tenths of a litre? The air-conditioning, and its generalization, especially in regions as warm in summer as the center, south and east of Spain, has been one of the biggest breakthroughs of the car in terms of comfort and safety. Why security? Because heat also affects them, and a lot of, the driver, can exacerbate the fatigue at the wheel and bet tricks. It is more efficient or not, and having air conditioning, who is able to circulate around Seville, with the windows downs, 15 August? It is ridiculous, don’t you think?

4. Allergy sufferers of the world unite… and cerrad the windows. Continuing with the topic of security, there is another very important factor to recommend closing the windows. The machines are modern, with filter anti-pollen, are much more cost effective to retain the pollen and the agents scattered in the air that we pester allergy sufferers. I speak from experience. A trip suffering from allergy symptoms, it is not only uncomfortable, but also dangerous. There are studies that say that at 120 km/h, a sneeze can make us move between 60 and 100 metres “blind” (DGT). Believe it or not, there have been accidents due to sneezing. And the antihistamines, especially the more powerful, can produce drowsiness and other symptoms incompatible with driving.

5. Learn how to use the recirculation. If the temperature difference between the interior and the exterior is very high, the air conditioner will have to work at peak performance getting air from the outside, if we activate the recirculation, the work that you have to perform will be lower, and therefore, save energy. In any case what is desired is a carrier well-ventilated, and the recirculation will only be used in very specific situations. For example, to change temperature very quickly, since the effort required of the compressor is lower. It is also advisable to use it in areas where the air quality is not good, a jam, a tunnel, or a parking lot. There are even cars that handle automatically activate the recirculation in these situations.

aire-acondicionado-vs-ventanillas-02-1440px6. Knows the tricks of your car. There are models that come with driving modes of savings, able to limit the power consumption of the air conditioning system. Sometimes these modes of air conditioning saving can be selected without changing the driving mode of the car. It is a solution to keep the fuel consumption.

7. In very hot days, ventilate your car before you climb aboard and connect the climate control. Not only will help the temperature on board is more pleasant, and we spend less fuel, but also to increase the durability of the climate control of our car. Try to park in the shade, don’t buy a car black (yes, they are nice, but from experience I also know that in the summer you can use your hood as a grill to make a bbq), open the windows for a few minutes before you leave for your trip. There are even videos that teach us tricks to ventilate quickly the passenger compartment of a car, like to leave open the passenger door and shake with insistence the driver’s door to evict the stale air out and warm through the greenhouse effect, present in the interior of the vehicle.

And what was said, first of all, common sense…

What uses more, air-conditioning or windows downs?