Barun Roy: A world of 'farmscrapers'

Is the world's first "farmscraper," super-tall farming high-rise, going to come up in Hong Kong? Or Shenzhen, a dense urban conurbation just across the border in the Pearl River Delta? Or will it be Changsha, a city in China's Hunan province? Wherever it might be, "farmscrapers" are the newest idea buzzing around among urban architects and planners, which they think will help contain the problem of rapid urbanisation and an equally rapid shrinking of land available for agriculture.

"Farmscrapers" take the idea of vertical farming, already accepted in the US and Europe as a judicious food security alternative, to totally unprecedented heights, and last August a Spanish architectural firm, Javier Ponce Architects, gave Hong Kong a glimpse of its vision of how unprecedented it might be. Ponce has proposed to build a series of what he calls Dyv-Nets, or Dynamic Vertical Networks - farming towers rising 187.5 metres into the sky - in the Tai Po district of Hong Kong's New Territories.

Made from lightweight recycled materials, the see-through but highly resistant structures would grow food using hydroponics on a series of rotating floor-plates that imitate Chinese rice terraces and expose crops to the maximum amount of sunlight. The towers would also serve as 360-degree viewing platforms and biodiversity hubs, incorporating a wide range of habitats.

Also in August, French architect Vincent Callebaut, tasked by Shenzhen authorities to find solutions for the sprawling city, released a concept that's as daring in its look as it's dramatic in its implications. He calls it "Asian Cairns," after the Gaelic word that means piles of stones, often used to mark out trekking trails. Callebaut's proposal is for six sustainable buildings over a 79-acre area and divided into ovular, blob-like sections that look like pebbles polished by years of running water. Each structure would be 1,300-feet high and have 111 floors, and each protruding blob, or floor, built around a central tower, would provide space for growing crops, grass, even miniature forests.

Together, Callebaut says, these "cairns" would form self-contained ecosystems, complete with wind turbines and solar cells. The water created and collected by the planted farms would be recycled for use within the buildings. Each pebble unit would also contain a mix of office, residential, and recreational space, giving his design an additional dimension.

At about the same time, ground was broken in Changsha for a 202-storey, 2,723-feet Sky City that would be the tallest building on earth when completed and combine the ideas of both high-rise living and high-rise farming. Its developers, the Broad Group, claim it will be completed by April 2014 and will contain, besides all the usual residential, official, and commercial facilities, extensive parks and vegetable farms, and even a 10-km walking street stretching from the first to the 170th floor. "Anything you need from cradle to grave, except a crematorium" is how they describe the $1.46-billion project.

Whatever eventually happens to these ideas, they certainly reflect a reality that's now accepted as unavoidable: If mankind has to avoid a major catastrophe in global food production, nations must design their urban future largely around vertical cities and agriculture. This precisely is the theme of an annual international design competition launched by Singapore National University's School of Design and Environment two years ago to seek out possible new solutions for an increasingly complex problem. Co-sponsored by World Future Foundation and Beijing's Vantone Citylogic Investment Corporation, the competition involves architecture students from 10 Asian, European, and US universities and will go on for two more years.

Urban farming was the theme of this year's contest and the competitors were given a square-kilometre site some 17 km to the west of Hanoi and asked to propose plans on how cities could grow food safely and sustainably to meet their daily consumption needs, using resources in an effective manner, minimising the use of water, and saving energy. All of their designs make one thing very clear: vertical is the way to go if horizontal inroads on the world's limited agricultural land, in many ways inevitable, are to be contained.

The problem is quite serious. Predictions are that food production has to increase by 70 per cent globally and nearly 100 per cent in developing countries by 2050 in order to meet the needs of 9 billion people expected to inhabit the earth by then, nearly 80 per cent of them in urban areas. But in the face of the growing competition for land and water resources, plus the fact that some 25 per cent of all land is highly degraded, the task of meeting those needs won't be easy unless alternative solutions are found and embraced.

That's where high-density vertical farming in urban areas becomes relevant. Some experts, in reports published in journals such as the Scientific American, say a one-square-block city farm, 30 storeys high, could produce as much food as can be grown on 2,400 horizontal acres.

rbarun@gmail.com