Architect Vincent Callebaut hopes future cities will farm the sky
Imagine stepping out of your high-rise apartment into a sunny, plant-lined corridor, biting into an apple grown in the orchard on the fourth floor as you bid "good morning" to the farmer off to milk his cows on the fifth.
You take the lift to your office, passing the rice paddy and one of the many gardens housed in the glass edifice that not only heats and cools itself, but also captures rain water and recirculates domestic waste as plant food.
No, this is not the setting for a futuristic movie about humans colonising a new planet.
It is the design of Belgian architect Vincent Callebaut for a 132-floor "urban farm" - the answer, he believes, to a better future for the estimated six billion who will live in cities by 2050.
With food, water and energy sources dwindling, the city of the future would have to be a self-sufficient "living organism", said the 36-year-old designer of avant-garde buildings some critics have dismissed as daft or a blight on the landscape.
"We need to invent new ways of living in the future," Callebaut said at the Paris studio where he plies his trade.
Each building, he said, must ultimately be a "self-sufficient, mini power station".
The quest for sustainable urban living has never been more urgent as people continue flocking to cities, which encroach ever more onto valuable rural land, gobbling up scarce natural resources and making a disproportionate contribution to pollution and earth-warming carbon emissions.
Enter Callebaut with his project Dragonfly - a design for a twin-towered "vertical farm" on New York's Roosevelt Island.
From each tower springs a large glass-and-steel wing, so that the edifice resembles the insect after which it was named.
The draft structure includes areas for meat, dairy and egg production, orchards, meadows and rice fields along with offices and flats, gardens and public recreation spaces.
Energy is harvested from the sun and wind, and hot air is trapped between the building "wings" to provide heating in winter. In summer, cooling is achieved through natural ventilation and transpiration from the abundant plant growth.
Plants grow on the exterior shell to filter rain water, which is captured and mixed with liquid waste from the towers, treated organically and used as fertiliser.
And at the base of the colossus is a floating market on the East River for the inhabitants to sell their organic produce.
"They made fun of me. They said I created a piece of science fiction," Callebaut says of his detractors.
But as awareness has grown of the plight of our planet, overpopulation and climate change, his ideas have gained traction, and the Dragonfly design has been exhibited at an international fair in China. He hopes to sell a design for a "farmscraper" in Shenzhen that will include housing, offices, leisure space and food gardens.
Callebaut has also drafted a concept for a floating city resembling a lily pad that will house refugees forced from their homes by climate change.
As yet, Callebaut has found no buyers for these big projects.