Credit: The Vertical Farm Project
The days of quaint market gardens on the fringes of the city supplying fresh produce straight to your dinner plate have been well and truly crushed under the giant tractor wheel of mass farming.
Suburban sprawl, combined with the vast economies of scale in operation in agriculture, have typically driven food production far from populated centres, with a corresponding increase in the cost of transport and risk of spoilage on route.
Yet, in a strange twist, a visionary microbiologist and environmental science lecturer at Columbia University in New York, sees our future cities populated with a new kind of market garden: one that doesn’t spread out, but that spreads up.
Perched on a spring-loaded chair in his office overlooking the Hudson River, and armed with two mobile phones, the silver-haired and effusive brainchild of vertical farming, Dickson Despommier’s enthusiasm is infectious.
“This technology disrupts everything,” he tells me. “What we all have to ask is, do you want to disrupt or be disrupted.”
Despommier runs me through the evolution of his idea from a long-ago project involving rooftop gardening in Manhattan, which, though a pleasant pursuit, he says can’t be sustained on a mass scale. But this seeded the concept and he started thinking bigger.
Looking at greenhouse projects – and thinking like a New Yorker, which means building up - the resulting concept is large-scale, indoor, urban agriculture. In skyscrapers.
Following this Despommier set up laboratory projects aimed at different design challenges and attracted a wide range of enthusiastic collaborators and contributors. He launched a website, The Vertical Farm Project (www.verticalfarm.com), around his essay outlining the argument for vertical farming, all of which has generated substantial buzz in media around the world.
If the idea of slapping farms in the middle of a metropolis seems muddled, Despommier has good reasons for thinking it could be a solution to some of the world’s most pressing problems.
According to the U.S. Census Bureau, the world population is expected to grow by three billion to 8.6 billion over the next half a century. By then, some 80 per cent of the developed world’s population will live in cities. The urbanisation trend is playing out in the developing world too, where sprawling mega-slums grow by the day.
At the same time, conventional farmland -- and grazing land -- takes up an enormous amount of rural space, with over one-third of the world’s surface in use for agriculture, according to a study directed by Wisconsin’s Centre of Sustainability and the Global Environment. That’s about 800 million hectares of arable land.
Despommier figures in the next five decades new arable landspace roughly the size of Brazil will be required to feed the world’s growing population - land that simply doesn’t exist.
His concept relies on using green methods of architecture and materials to build skyscrapers that house, grow and produce crops. Newly designed materials and technology such as cheaper heliostats, which reflect sunlight where it's needed, more efficient photovoltaic solar panels for energy and system-wide recycling are all integral to the potential success of such a building.
One unusual feature of the design uses zebra mussels (Dreissena polymorpha), an invasive species in the USA, to filter water. These can clean urban sewage effluent to a state where it is suitable for irrigation.
“Outside, one acre of land means one crop per year,” says Despommier. “Indoors, you can grow one crop every three months. You get four crops a year. That’s per layer in the building. A [New York] city block is five acres. Five acres times four crops a year per acre ... adds up to a bigger number!”
Despommier's estimates suggest that 150 such buildings could feed the entire city of New York for a year. Indoor crops also require less pesticide and are not so subject to the whims of nature: such as the drought devastating Australian wheat crops.
However, vertical farming is not without its challenges. One would be light – with artificial lighting sucking a lot of electricity and putting out a great deal of heat. Another is cost, with some A$93 million per building to construct and A$5.5 million a year to operate.
Opinions amongst experts vary on whether the project can succeed. Creating conditions for photosynthesis is a commonly cited problem, and some figure the crops would not have a high enough yield to make economic sense.
“My biggest reservation is that the basic premise is flawed. We already know how to increase food production from existing land resources, particularly in areas with surplus land such as sub-Saharan Africa. It's just that we do it incredibly badly at the moment,” says Rob Brook, a rural development researcher at the University of Wales in Bangor. “This is a rich person’s pipe dream.”
But Luc Mougeout, an advocate of urban agriculture at Canada’s International Development Research Centre, says the vertical farm is not only possible, but will happen within this generation. “It would collect at one site a diversity of elements already at work in some form or another around the world,” he says.
“What he would do would be to deliberately bring all these components together into a single design, thereby making these components more interactive and effective than ever.”
Columbia University is already connecting Despommier to potential backers. He’ll be in Dubai in March 2008 at an urban habitat world conference and has been contacted by venture capitalists from the Middle East, China and the Netherlands interested in establishing a centre for urban sustainable agriculture.
If the vertical farming vision becomes a reality, we could find ourselves once again enjoying fresh fruit and vegetables sourced from just around the corner, except these might come from the 45th floor.
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Michael Dumiak is a science writer based in Berlin, Germany.
