In the effort to move society toward sustainability, agriculture presents some of the thorniest challenges. Although to a casual observer it might seem to be a “green” activity, most modern farming actually has an enormous environmental footprint. Globally, agriculture accounts for about 70% of fresh water withdrawals, 20% of fossil fuel use, and is a major source of chemical runoff and greenhouse gas emissions.
Some argue that despite its drawbacks, modern high-intensity agriculture represents the best hope for boosting yields to feed the planet’s growing population. But sustainability advocates are increasingly proposing more environmentally-friendly methods, particularly ones that can be applied where most people actually live: in cities.
Urban agriculture encompasses a wide variety of different concepts, ranging from vegetable plots in vacant lots to rooftop gardens to actual multi-acre farms. One of the most ambitious ideas is called “vertical farming:” multi-level buildings, even skyscrapers, dedicated to growing crops indoors in an ecologically balanced environment.
In Singapore, one of the most densely populated cities on earth, engineer-turned-entrepreneur Jack Ng is at the cutting edge of this concept. His company, Sky Greens, recently launched the world’s first commercial vertical farm: a collection of four-story greenhouses, each containing tall towers holding trays of leafy greens. The trays rotate slowly up one side of the tower and down the other, exposing the plants to a nutrient bath at the bottom and sunlight at the top.
This model presents numerous advantages over outdoor farming. It requires no chemical inputs, enables year-round crop production, and eliminates losses due to severe weather. Water is filtered and reused, so there is no runoff and the system requires just a fraction of the water needed for traditional outdoor irrigation. While the cost of city real estate is higher, this is offset by lower transportation costs and higher productivity per square foot. Dickson Despommier, a professor of ecology at Columbia University and one of the leading advocates for vertical farming, estimates indoor productivity could be 10 to 20 times higher than outside.
Another potential benefit of urban vertical farming is that it could allow the earth to heal. Around the world, vast tracts of tall-grass prairie, rainforest and hardwood forest have been leveled for agriculture, and more are destroyed every day. If food production were moved to cities, many of these areas could be allowed to return to a more natural state, creating havens for biodiversity, carbon sequestration and even ecotourism.
There are non-environmental benefits as well, such as urban jobs, fresh produce for city inhabitants and reduced vulnerability to supply disruptions. In a country like Singapore, which imports more than 90% of its food supply, locally-grown food doesn’t just taste better, it is also an issue of national security.
Vertical farming is in its infancy and is not poised to become the status quo anytime soon. But as concerns mount about the environmental risks and vulnerabilities associated with outdoor agriculture, more countries are likely to follow Singapore in exploring the benefits of growing upward.
Contributed by Wyatt C. King, Director, Albright Stonebridge Group
Posted: 9/25/2013 12:28:49 PM by
Mary Kestner | with 1 comments