It has been estimated that by 2050, as much as 80 percent of the earth’s population will reside in cities. Considering that, by conservative estimates, the total population will total 2 billion, the question is, how are we going to feed our cities in an ecologically friendly way? Consider the high-tech, high-yield greenhouse technology developed by the Swedish-American company known as Plantagon.
The company’s three greenhouse designs are based on a similar spiral ramp system. Plants are placed in pots, which are then fastened into trays equipped with a light-sealed nutrient solution reservoir. The pots are irrigated about three times a day using an ebb-and-flow technique, while the capillary mat at the bottom of each tray protects the individual plants from drying out. New plants are carried to the top of the spiral via a special elevator, then slowly rotate down over the course of their growing cycle.
When plants reach the bottom of the greenhouse, they are harvested via machine. After the harvest, the trays and pots are disinfected, and the pots are separated and replanted with more seeds for the next round in the cultivation loop. After those seeds sprout, the pots are once again placed in trays and elevated to the top of the growing helix to repeat the process. According to Plantagon, this system produces 3–10 more crops per square meter than a standard greenhouse.
Plantagon envisions this tech at work in three different greenhouse designs developed specifically for urban environments. The Integrated option is a facade that can become a part of any building design, from a tall skyscraper to a smaller, mid-size building. (This option makes use of three parallel conveyors that provide the building with diffuse daylight, “suitable for regular office activity,” and avoids the one-sided plant effect by turning the pots as they make their way up the ramp system from side to side.) The Parasite version of the greenhouse is essentially the same, but suitable for retrofitting to existing buildings.
The Stand-Alone is a dome (like The Globe greenhouse) and, as the name suggests, is a building in and of itself, exclusively dedicated to urban food production.
The PlantaSymbioSystem employed by Plantagon was developed via a joint initiative between the Swedish Government and Swedish industry. The idea is that such large-scale greenhouses can work symbiotically with the built environment of the city, including its industrial buildings. Greenhouses can make use of the surplus heat produced by such buildings to become more energy efficient, filter carbon dioxide from the air, and make use of food waste for fertilizer.
All three greenhouse designs are adaptable to local architecture, are scalable in size, and can be integrated in the city’s existing utility infrastructure. Plantagon sees them as playing a part in LEED certification via their integration into buildings — or, as a stand-alone building option, even gaining certification on their own.
Plantagon broke ground on its first greenhouse in February in Sweden, and has since signed Memorandums of Understandings with entities as diverse as Tongji University in Shanghai and the Onondaga Nation in New York. It has been named one of the most innovative companies in Europe, and recently won the 2012 Swedish-American Chamber of Commerce New York-Deloitte Green Award.