Jorge García-Dihinx, physician: "On short trips, roll down your car windows whenever possible."

Nowadays, air conditioning is the best ally when driving during the summer months, as it helps maintain a comfortable temperature inside the vehicle. However, constantly driving with the windows down and the air conditioning on can have negative consequences.

First, Dr. Jorge García-Dihinx points out that modern car windows block out all the infrared rays from the sun . Furthermore, the interior of the vehicle fills with carbon dioxide, which hinders air circulation and causes drowsiness .

Why is it important to drive with the windows down sometimes?

García-Dihinx specifies that "the glass doesn't allow the sun's infrared (IR) to enter, so as to avoid creating a greenhouse effect inside the car." With this, the doctor explains, " all UV-B, part of UV-A, and between 40 and 60% of the restorative infrared are blocked ," so that "the natural spectrum of the sun is not received."

García-Dihinx also shows the famous photo of the truck driver whose left side of his face looks older due to the sun shining through the window. Therefore, he advises using the car with the windows down on short trips, as this is the best way to receive natural sunlight, according to the Aragonese doctor. In short, if we open the windows, we will receive the full spectrum of sunlight (UV-B + UV + visible + restorative IR).

What consumes more energy: lowered windows or air conditioning?

During the summer, most drivers in Spain have faced this dilemma: should they use the air conditioning or roll down the windows? The decision usually depends on both the amount of time they plan to spend in the car and fuel consumption.

From a fuel-saving perspective, there's no single answer, as factors such as speed and vehicle age influence fuel economy. According to a study conducted by the US Society of Automotive Engineers , when driving at low speeds, opening the windows is the most efficient option . However, at speeds exceeding 80 km/h, it's advisable to use the air conditioning. This is because having the windows down reduces aerodynamics , which significantly increases energy consumption.