One of the ironies of world tourism is that Western travelers flock in droves to locations in hot, sunny climates to experience different cultures, yet many of them demand that their hotel rooms feel just as cool as their homes. Usually, this involves some kind of energy-hogging air-conditioning device that can tax the overloaded grids of these rural locations.
Fortunately, there are some natural forms of A/C that get the job done without turning an exotic natural location into a sealed-off American suburb. On the Spanish island of Ibiza in the Mediterranean Sea, the Hotel de Ushüaia has incorporated an ingenious method to keep its guests cool using a living vertical garden and the magical properties of evaporation.
The hotel’s undulating terracotta wall, called the Eco.bin Greenwall System, was designed by Urbanarbolismo and built with the help of construction firms Alicante forestal and Alijardín. Urbanarbolismo describes it as the first use of a green wall specifically as an air-conditioning tool.
Eco.bin is made of hundreds of hollow ceramic containers that are turned on their sides and interconnected in a grid pattern, forming a perforated wall. Inside each opening, plants native to the Mediterranean climate are placed in substrates. Through a regular schedule of drip and mist irrigation, the plants retain moisture, which is enhanced by the porosity of the terracotta.
As the sea breezes blow through the openings, evapotraspiration, or the release of water vapor from the plants, cools the air around them and helps lower the temperature in the hotel’s courtyard. The ventilation also allows for the roots to trap and absorb pollutants from the air.
Plants used in the Eco.bin wall include aeonium, crassula, echeveria, euphorbia, kalanchoe, sedeveria, and sedum. Because these succulent plants are so well suited to the island’s semi-arid climate they don’t require much substrate and are fairly hardy. Some of the plants that get most of their water and nutrients directly from the air, reducing the need for drip irrigation.
If the Hotel de Ushüaia has any problems with the plants, the staff can easily replace individual plants without the need for extensive knowledge of gardening. As an added benefit, the high curved wall at the hotel also acts as a sound absorption barrier.