Hydroponics - Food Production of the Future?

In 1960, when the world population was only 3 billion, approximately 0.5 hectare of cropland per capita was available, the minimum area considered essential for the production of a diverse, healthy, nutritious diet of plant and animal products. Increases in grain production brought about by irrigation and synthetic fertilizer-pesticide inputs have peaked and begun declining.

Although, the cultivable land has been increased by clearing more forests and improved irrigation techniques, the available per capita land today is reduced to .25 hectares (current population of 6 billion).

Over the past 40 years, approximately 30% of the world's cropland has become unproductive. During the past 40 years nearly one-third of the world's cropland has been abandoned because of soil erosion and degradation. About 2 million hectares of rain fed and irrigated agricultural lands are lost to production every year due to severe land degradation.

As consumption surpasses production, the world's stocks of stored grain have been falling relative to each year's use. When supply can no longer meet demand, free market price competition may starve the poor.

By 2050, when the world population reaches 9 billion, the available per capita land will reduce further to .16 hectares (17,222 sq feet or 0.4 acres). With conventional agriculture it is impossible to feed the entire population.

Hydroponics is the only alternative to achieve food security for all. Improved space and water conserving methods of hydroponic food production are already in experimental stages and have shown promising results.

Dr. Dickson Despommier, a professor of microbiology at Columbia University, originally came up with the idea of the Vertical Farm Project, as a solution to the future pressure on land and resources and as a way of reducing the carbon footprint of our cities. Since the beginning of the project, a number of environmentally friendly ‘vertical farms’ have been designed for New York, Toronto and Paris.

Toronto scientist, Gordon Graff designed a concept building known as the SkyFarm which would sit in the centre of the city’s theatre district. His 58 floor tower design could provide enough food at the centre of the city for an estimated 35,000 people, every day. It would comprise of different crops, vegetables and fruits, all being grown hydroponically, using water in place of soil. During hydroponic growth, plants are fed nutrients dissolved in water in a strictly controlled environment. 

The benefits to the environment of producing food in vertical greenhouse-like farms in the centre of town would be multiple. Not only are distribution vehicle emissions cut by growing food in the place where it will be eaten, but there is also no need for ploughing, no digging, and no seasonal droughts. Crops are protected from the elements and run off or ‘dirty water’ is eliminated as water can be recycled within the hydroponic system of the building. 

Also, because plants grown hydroponically are in a controlled environment, with no soil, there are also no soil borne diseases or pests to worry about; the city’s food could be produced without the need for chemical pesticides or fertilizers. 

Hydroponic growth requires only one twentieth of the water used to irrigate a farm growing the same number of plants, yet yields are higher. Because there is a continuous flow of nutrients to the plant, the plant can concentrate its energy on producing fruit rather than roots. Hydroponic lights and a CO2 rich atmosphere within the building could also increase food production by stimulating photosynthesis and lengthening the daylight hours available to the plants.

Some more interesting links on the subject

Vertical Farm
Vertical Agriculture
Skyscraper Farm