Set to be deployed as a nontraditional façade for the planned Hotel Forest in Barcelona, the Artificial Leaf is a draping system of light-emitting modules suspended on steel mesh. The scheme is based on the analogy that if a city is a forest, each building is a tree. Adding a net of individual modules is akin to putting leaves on the tree, and like an actual plant, these leaves both generate and expend energy by harnessing the energy of the sun.

Each module is a convex disk that is 12½ inches in diameter and just over 2 inches thick at the center. One side is made from translucent plastic and the other from clear glass. Contained in each disk is a small photovoltaic cell, a light sensor, a battery, and an RGB LED source. The modules are clipped to the steel mesh and are programmed in tandem to generate different color effects—mixing different intensities of red, green, and blue creates single- and multicolored lighting displays across the façade.

The jury was impressed by the goal of making a building's façade a dynamic part of the urban landscape, and in so doing engaging the public with the built environment. “It is a way of inducing a pretty boring building envelope to deliver something that was really spectacular for the city, in its capacity to react and respond to its urban context,” said Chris Genik. “It seems like a layer of interaction that cities should become increasingly vested with.”

The jury also saw the potential for other applications of the net, both as a renovation tool and as an energy-gathering device. “This is a fresh and potentially more playful way to clad buildings in adaptive reuse situations,” said Blaine Brownell. “You're not constrained by the modules that currently exist or performance issues embedded within an existing skin. You can simply loosely drape something like fabric that not only performs for the building—or at least has that potential—but also can create this really interesting effect in public space.” The hotel and its unconventional façade, both designed by Cloud 9, will open in 2010.

PROJECT Artificial Leaf

CLIENT Prestige Hotels, Roses, Spain—José Moyano, Juan Marull, José Maria Moyano, Ignacio Marull

PROJECT LOCATION L'Hospitalet de Llobregat, Barcelona, Spain

ARCHITECT Enric Ruiz Geli/Cloud 9, Barcelona, Spain—Enric Ruiz Geli (principal architect); Max Zinnecker (project architect, Hotel Forest/research and development for Artificial Leaf)

LIGHTING TECHNOLOGY iGuzzini Illuminazione—Adolfo Guzzini, Franco Nibaldi, Josep Masbernat, Alex Chiva, Massimo Gattari


Enric Ruiz Geli
Enric Ruiz Geli
Max Zinnecker
Max Zinnecker