April 1, 2010
Their Day in the Sun
An exhibition of student designs gives Grätzel solar cells their due.
The Swiss chemist Michael Grätzel’s solar cells were not invented to activate hanging air fresheners. Nor were they meant to power bikes-only road signs. And they were most certainly not created to charge electronics for homeless people. But in the hands of intrepid industrial-design students, this low-cost solar technology has become a source of, yes, sunny possibilities.
In the fall of 2008, EPFL + ECAL Lab tapped students from two schools in Lausanne, Switzerland—as well as California College of the Arts (CCA), in San Francisco; the Royal College of Art (RCA), in London; and Ecole Nationale Supérieure de Création Industrielle (ENSCI), in Paris—to envision products keyed to the Grätzel cell’s singular capabilities. The device converts light to electricity using a sunsensitized dye, much like photosynthesis. It’s thin and bendable and can assume virtually any color, making it a felicitous material for style-minded designers. At the moment, though, it’s too inefficient to harvest energy at a large scale and shows the most promise powering small household objects.
With a crack team of designers at the chalkboard (Yves Béhar, Christoph Behling, and Sam Hecht among them), students spent the semester learning to operate at the busy intersection of green technology and design. Their work makes its American debut this month in the exhibition Sunny Memories, at San Francisco’s Wattis Institute for Contemporary Arts, then travels to New York’s Center for Architecture in May. “Designers are able to imagine new types of solar objects,” says Nicolas Henchoz, director of the EPFL + ECAL Lab, which is a partnership between Lausanne’s premier science institution (Ecole Polytechnique Fédérale de Lausanne, where Grätzel conducts his research) and the neighboring arts university (Ecole Cantonale d’Art de Lausanne). “But normally, students don’t have strong roots in technology or energy. Here they had to understand how [the solar cell] works. It was really learning by doing.”
Each university approached the assignment differently. At RCA, some students improved existing gizmos like flashlights and insect repellents, while others considered the cell’s broader potential (in a massive inflatable sunshade, for instance). At CCA, Béhar encouraged his class to think locally. “I wanted students to dig into what I believe makes San Francisco and the Bay Area very different from other places,” he says. “It’s so much at the crossroads of new lifestyle and technology. I wanted them to think of this project almost as a sociological and behavioral exercise rather than purely technological.” We can credit this approach with producing the solar-powered bike signage.
But first everyone had to get up to speed on the technology. In the early days of the semester, Léa Longis, a 25-year-old student at ENSCI, experimented with colors: how a red cell soaks up light versus a green cell, purple versus yellow, and so on. Working with engineers from EPFL, she discovered she could generate the most energy by reflecting variously colored cells in a mirror. Her resulting project, Helio, is a digital radio whose solar cells fan out whimsically, like a kaleidoscope, in a translucent box. “In France, design is about making wood chairs, not really mixing technology and design,” she says. “For me, it was a great experience to collaborate with engineers and work on such a nice technology. It’s the way design should work.”
A handful of students conceived of projects that could go into production immediately, and Henchoz says there are “ongoing discussions” to that end. Other work is perhaps better suited to the art gallery. One CCA student thought up a “floating chair” that would dot parks and collect energy during the day, then light up at night—if only the cells were powerful enough. A team at ECAL created Bubs, an electronics charger made of white fabric that would clip onto homeless people’s shopping carts. It’s an innovative pairing of fabric and solar technology, though it’s hard to imagine that it’ll find much of an audience beyond the sympathetic halls of academia. Nevertheless, it’s the prettiest damn charger for homeless people ever made.