Algae “bioreactors” absorb carbon dioxide, while producing oxygen, heat, and several types of biomass, including material that can be turned into fuel or food. That’s why they’re potentially very useful for cities that need heat and calories, and that want to cut down on pollution.
We’ve seen before how this can work: Most of this Hamburg building was powered by large algae panels clad to its outside. (Yes, it really worked). Now comes another prototype: the “Urban Algae Folly,” from U.K.-based designers Marco Poletto and Claudia Pasquero.
Built for the “Future Food District” at the ongoing Milan Expo, the canopy is made of metal sections welded together with transparent tubes and pipes carrying a mixture of water, CO2, and nutrients. As sunlight hits the liquid, it encourages photosynthesis, which multiples the algae until the pipes are thick with green gunk.
The “Folly”—a building made for decorative or whimsical purposes—contains a series of motion-sensors inside. When humans come into the space, the system speeds up, affording more shade. Poletto says the window is almost opaque on hot sunny days, and that, with evaporative cooling on the outside, the algae can reduce temperatures by a full 10 degrees Celsius.
“The folly produces the equivalent oxygen for three adults to survive. It takes 25 urban trees to do that,” he adds. “It also produces enough protein for 12 adults, with no animals being killed and no methane being released.” Algae can be made into spirulina, a dietary supplement used in ice cream and several other products.
Poletto and Pasquero are hoping to commercialize the idea and make full-blown buildings one day. “I’m more than convinced we will see [them],” Poletto says. “The material technology could fit large and permanent architectural scenarios. Now we only need investors with the vision to roll this out on a larger scale.”