World's Largest Single-Domed Greenhouse Will Open in France

The world's largest single-domed greenhouse, "Tropicalia," is expected to be completed in 2024 in France's Cote d'Opale. Coldefy, a French architecture firm, has presented the ambitious project which will span over 215,278 square feet (20,000 square meters).

Cut off from the world outside, the greenhouse will have a variety of flora and animals, such as exotic flowers, butterflies, hummingbirds, Amazonian fish, turtles, caimans, water gardens, waterfalls, and ponds. Load-bearing columns will be absent internally, ensuring that views are not obstructed.

Designs of the Tropicalia are now on display at the 17th Venice Architecture Biennale till November 21. Coldefy and the non-profit Zuecca Projects are showcasing their ambitious plans for the doom, which include architectural models, drawings, and videos.

Not only that but the greenhouse's architectural and technical aspects, as well as its unique sustainable air treatment engineering, are being shared by the duo.

Tropicalia: A 'bubble of harmony'

The 115-foot-high (35-meter) structure is designed to incorporate the natural environment, so it will be partially embedded in the ground, flawlessly integrating into the French landscape with the installation of a second exterior wall of flora.

The roof will be made of pressurized thermal pillows fitted into an aluminum frame, and inside, the dome will be heated to 82.4°F (28°C) to ensure lush vegetation. 

The entire facility will be self-sufficient in terms of energy. A double dome design is planned to provide optimal thermal isolation, and all heat produced will be recycled and stocked. 

"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, told ArchDaily when the project with initially announced in 2018.

Since that time, the company involved with Coldefy switched to ENGIE. However, the structure and purpose remain the same. 

Terraotherm technology, which is described as an air-water heat exchanger with low energy consumption and minimal carbon emissions, will recycle the greenhouse's thermal energy and the excess energy will be exported through a heat network into nearby buildings. 

The greenhouse will have an 82-foot-high (25-meter-high) waterfall, 82-foot-long (25-meter-) pool with koi carp inside, and an Olympic-sized pool with Amazonian fish. Visitors will be able to see these fish through a glass surface. The more courageous will be able to opt for a platform and pontoon.

Accompanying the tropic setting, the greenhouse will also have an auditorium, restaurant, and a scientific section complete with a conference room, laboratory, and clinic for worldwide collaboration. The plan is estimated to get more than 500,000 visitors per year when it opens in 2024.

Update: This article has been updated to state that the new company affiliated with the project is ENGIE.