How to beat the heat: Maximise fan efficiency this summer

Due to its ease of use and low operating costs, a fan is often chosen as a cheaper alternative to expensive air conditioning systems. However, it is essential to remember that a fan cannot cool the air; it merely sets it in motion.

But how should you use a fan to maximize its efficiency? The critical element here is the proper placement of the device and using the principles of physics to our advantage.

A fan can prove invaluable on hot days. This device is handy in the evenings when we need an effective way to cool a room, such as a bedroom.

The best approach is to position the fan to push warm air outside rather than pull cool air inside. The device should be placed inside the room and directed to aim outward airflow. This will help remove the warm air from the room.

Distance is crucial. Many people make the mistake of placing the fan directly in front of the window, which only sets the air directly in front of the fan in motion. This is where the Bernoulli effect comes into play.

The Bernoulli effect will occur if the fan is placed slightly away from the window, with the rotor blades positioned at the level of the open window. The air flowing from the fan creates a low-pressure area around it, which attracts additional air from the surroundings. This allows for faster and more efficient expulsion of more air.

But how far should we place the fan? This depends on many factors, such as the rotor blades' diameter and the window's size. Therefore, it is worth experimenting to ensure that the air cone moved by the fan reaches all four corners of the window.

Another trick worth trying is negative pressure ventilation. Cool air can enter the room more efficiently when warm air is pushed outside. Open a window opposite the fan to allow cooler air to flow inside.