From The Economist – Dec 9, 2010

WHEN you run out of land in a crowded city, the solution is obvious:
build upwards. This simple trick makes it possible to pack huge numbers
of homes and offices into a limited space such as Hong Kong, Manhattan
or the City of London. Mankind now faces a similar problem on a global
scale. The world’s population is expected to increase to 9.1 billion by
2050, according to the UN. Feeding all those people will mean increasing
food production by 70%, according to the UN’s Food and Agriculture
Organisation, through a combination of higher crop yields and an
expansion of the area under cultivation. But the additional land
available for cultivation is unevenly distributed, and much of it is
suitable for growing only a few crops. So why not create more
agricultural land by building upwards?

Such is the thinking behind vertical farming. The idea is that
skyscrapers filled with floor upon floor of orchards and fields,
producing crops all year round, will sprout in cities across the world.
As well as creating more farmable land out of thin air, this would slash
the transport costs and carbon-dioxide emissions associated with moving
food over long distances. It would also reduce the spoilage that
inevitably occurs along the way, says Dickson Despommier, a professor of
public and environmental health at Columbia University in New York who
is widely regarded as the progenitor of vertical farming, and whose
recently published book, “The Vertical Farm”, is a manifesto for the
idea. According to the UN’s Population Division, by 2050 around 70% of
the world’s population will be living in urban areas. So it just makes
sense, he says, to move farms closer to where everyone will be living.

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