Air conditioning without electricity: these Mexican students invent a passive system with recycled materials

In the heart of Altamira, a town in the Mexican state of Tamaulipas, five students of the municipal high school gave birth to a surprising invention: a passive ventilation system built entirely with recycled materials. The goal of the project is as simple as it is ambitious: to offer low -income families a sustainable alternative and accessible to expensive air conditioning systems.

The group, formed by Milena Vázquez, Aymar Izagurre, Lorenzo Méndez, Juan Rubén Zárate and Oscar Galicia, baptized their prototype Eco freezer slim. This device, in the shape of a mini wall air conditioning, was designed to cool the internal environments of approx 4 ° Cwithout any consumption of electricity.

A thermodynamic principle at the service of the environment

The operation of the eco freezer slim is based onJoule-Thomson effecta physical principle according to which a gas, once compressed and then expand quickly, tends to cool down. Although this effect is usually applied in complex industrial systems, students have managed to reproduce a simplified and accessible version.

The device uses 1.5 -liter plastic bottlescut and whip so that the hot air enters the wider part (facing outwards) and comes out of the neck of the bottle, which acts as a narrow duct. When the air is forced to pass through this narrowing, it compresses slightly and cools down to the exit, thus offering a Fresher air flow within the house.

However, the students admit that, since it is a passive and artisan system, it is not possible to perfectly replicate the conditions required by the Joule-Kelvin effect, which provides for rigorous control of the pressure and temperature of the gas.

A mini air conditioning made of cardboard, wood and plastic

To build the eco freezer slim, students used common and easily available materials: recycled cardboard, wood And Pet bottles. The supporting structure is in pressed cardboard, while the bottles act as tunnels for the passage of air, as Lorenzo Méndez, one of the boys involved: explained:

We thought it as a small wall air conditioner.

According to the group, the system works best if installed near a window, where the natural air movement helps the cooling process.

The first tests conducted directly in the children’s homes confirmed the goodness of the project: the initial temperature of 27 ° C it gradually dropped to 24 ° Csignificantly improving the perception of heat inside the room.

The echo freezer Slim was born as a response to one school challenge on eco-innovationbut quickly attracted the interest of the local community. With this system, young inventors hope to Improve the quality of life in the poorest homeswhere access to cooling systems is often limited or non -existent.

Now their desire is that the project comes supported by entrepreneurs and institutionsso as to develop a broader scale production and spread this low-cost solution also in other regions affected by the extreme heat.