Berlin architects Allison Dring and Daniel Schwaag of Elegant Embellishments have created a facade that reduces air pollution. A report.
22 million residents and 4.5 million cars. These numbers define Mexico City. In other words: It’s a people-eating juggernaut that pumps filth into the air. A mere 20 years ago, Mexico’s main metropolis was the world’s capital of air pollution.
Ever since, campaigns like “Pro-Aire” have eliminated some of the most environmentally-damaging vehicles and modernized public transport. Yet even green rooftop gardens are just a drop in the red-hot asphalt jungle.
After all, the number of vehicles keeps going up, increasing by 200,000 every year. City administrators are desperate for solutions to the nitrogen oxide (NOx) crisis. And welcome harbingers of change like the following: A smog-eating hospital, or – to be more precise – its affixed facade containing titanium dioxide pigments, neutralizes the emissions of an impressive 1,000 vehicles per day.
Swiss cheese-style diatoms
The facade of the Hospital General Dr. Manuel Gea González on busy Avenida Calzada de Tlalpan resembles a giant slice of Swiss cheese, dotted as it is with holes and gaps. Somehow, it reminds the viewer of outsized diatoms overgrowing the building.
Daniel Schwaag appreciates the comparison. According to the Berlin architect, „these are quasi-crystalline, non-repeating structures.“ The resulting pattern resembles Islamic ornaments, generating ever-new images from just a few basic shapes. Their arrangement is regular, yet ramified.
At the same time, these interwoven patterns represent a large surface across a compact space: The module by Elegant Embellishments is designed to transform a maximum of noxious airborne NOx into harmless water, carbon dioxide, and calcium nitrate.
A field test in Manila produced phenomenal results: Each square meter of the module removed 0.26 grams of NOx per day. The module’s unusual structure, which captures light from all angles, plays a major role – as does the use of titanium dioxide.
Large surfaces = large amounts of smog absorption
Schwaag explains that while it would be possible to spray the catalyst onto existing buildings, it would not have the same effect. Just like catalytic converters in vehicles, titanium oxide requires a large surface to neutralize a maximum amount of nitrogen oxides.
In both cases, geometry determines the outcome. For a perfect result, Allison Dring’s and Daniel Schwaag’s “elegant embellishments” simply use freely available, yet variable sunlight.
To this end, the convoluted, multi-angular surface of their “prosolve module“ is not optimized for a particular solar angle, but instead facilitates NOx scrubbing via light energy throughout the day.
In theory, such facades could be spun to infinity. Or moved indoors, as ceiling sculptures, yet Dring and Schwaag remain most proud of their Mexico City project, which demonstrates the efficiency of their new facade across a large surface for the first time.
Biodynamic cement at the Milan Expo
And the unusual facade is flanked by other measures. This year’s Milan Expo backed its own ambitious motto “Feeding the Planet, Energy for Life” with several tangible improvements. The Italian Pavilion, designed as a white tree made of concrete by the Rome-based Nemesi Studio, also doubled as a 13,000-square meter smog-eater.
Federica Provaroni of Nemesi Studio reveals that they used hundreds of tiles of “biodynamic” cement to capture air pollutants. And demand keeps going up. “Since September, the manufacturers Italcementi have been selling the material all over the world.”
The age of intelligent facades
Right now, the facade of the Hospital General Dr. Manuel Gea González remains a reference project, an acupuncture needle in the behemoth of a body that is Mexico’s capital. Yet the structures in Milan and Mexico City herald the start of something new: an age of intelligent facades that promise to make life in some cities more liveable.
For Mexico City – and its smog problem – is everywhere. It’s in La Paz, Manila, Hong Kong, or New Delhi. The “functional ornament,” according to Daniel Schwaag, helps to make invisible technologies tangible. Even when the reactions are relegated to the nano sphere, the new structure clearly shows that it takes a will and idea to effect urban change.
He adds that, “some technologies are only interesting on an urban scale.“ We can only agree.
Header image: Elegant Embellishments