Smithsonian.com (05/26/15) Matchar, Emily
The Expo 2015 world's fair in Milan featured a gazebo covered with an algae-filled plastic forming a living "skin." The 430-square-foot gazebo is made of ethylene tetrafluoroethylene, a transparent plastic building material used in the Water Cube aquatics center built for the 2008 Beijing Olympics. The gazebo's hollow interior is filled with water and a type of algae called spirulina. The algae grows with more sun, darkening the gazebo and providing shade underneath. High-protein spirulina is often used as a dietary supplement, and every week or two, some of the algae is harvested for food. Future plans include growing algae that can be harvested for biofuel. Algae also absorbs carbon dioxide and produces oxygen. The gazebo produces 4.4 pounds of oxygen per day, according to designer Marco Poletto. He envisions using the technology on a larger scale in the future, with entire buildings clad in "a productive architectural skin" that would provide oxygen, produce food or biofuel, and provide shade. After observing visitors interacting with the gazebo at the Milan Expo for six months, Poletto and his partners plan to take what they have learned and incorporate it into future designs.