French firm Coldefy & Associates has unveiled images of their design proposal for the world’s largest tropical greenhouse under one roof. Situated in Pas-de-Calais, France, “Tropicalia” will cover an area of 215,000 square feet (20,000 square meters) featuring a tropical forest, turtle beach, a pool for Amazonian fish, and a one-kilometer-long walking trail. The biome aims to offer a “harmonious haven” where visitors are immediately immersed in a seemingly natural environment under a single domed roof.
The scheme will feature a “double-dome” of 200-foot x 13-foot (60-meter x 4-meter) ETFE strips forming a pressurized “cushion,” allowing UV light to pass through while controlling thermal conditions inside. A third layer of ETFE underneath the structure will accumulate heat generated by the greenhouse effect to be exploited for thermal energy. In order to further enhance the scheme’s energy performance, and to integrate the large structure with its natural surroundings, the dome will be partially embedded in the landscape. When combined, these measures create an energy-self-sufficient scheme allowing for energy to be redistributed to surrounding buildings.
This double insulating dome will protect the tropical ecosystem in summer and maintain its temperature in winter. The partial burial of the greenhouse will reinforce this insulation. The excess heat can therefore be directly used, stored or redistributed to our neighbors as part of a network of private heat or a “smartgrid.” – Denis Bobillier, Technical Director of Major Projects, Dalkia
The environmental conditions created by the dome allow for an “exceptional oasis for tropical flora and fauna” beneath. Visitors are led along a kilometer-long path, encountering an 82-foot-high (25-meter-high) waterfall, 82-foot-long (25-meter-long) “tactile pool” filled with koi carp, and an Olympic-sized pool filled with Amazonian fish, some growing up to 3 meters in length. Visitors can experience these fish through an aquarium-style glass surface, or more daringly, via a platform and pontoon.
To accompany the tropical environment, Tropicalia will contain an auditorium, bar/restaurant, bed and breakfast, and a scientific area dedicated to national and international collaboration, containing a conference room, laboratory, and clinic. When opened, the scheme is expected to attract 500,000 visitors per year.
Tropicalia is due to begin construction in 2019, with a planned opening in 2021.