22 July 2007

Vertical Farms

Approximately 12,000 years ago the human race created one of the most important innovations in history, agriculture. By growing their own food humans were freed from the constant search for food by hunting and gathering. This allowed humanity to get on with the job of creating civilization. Agriculture has come a long way in the last 12,000 years and we have all reaped the benefits. In first world nations we can walk into a shop at any time and be sure of having a large range of fruit, vegetables and meat available.

However conventional farming may not do the job for much longer.
  • By 2050 it is estimated that we will need an additional area of land 20% larger than Brazil to meet the food demands of the increased population.
  • Additional land will be required to grow crops for biofuels to replace oil and coal.
  • Climate change is already causing adverse weather conditions such as drought and flood making crop yealds less reliable.
The increased land use will have a devastating effect on the natural habitats of many species and the human race will still be unable to feed itself. Things look pretty grim. However the vertical farm may be the solution to our problems.

The vertical farm is a concept by Dr. Dickson Despommier of Columbia University, it takes two well established ideas (Hydroponics (growing plants in liquid nutrient solution rather than soil), and indoor farming) and pushes them to their logical conclusion. A vertical farm looks more like a office building than a farm and is powered by solar, wind and self-produced biofuels. Each floor contains 2 layers of hydroponic crops. Depending on the crop this means that at any time each floor can give between 4 and 30 times as much food as the same area of soil. The plants will also act as a water purification system not only for themselves but for the surrounding community. In addition power can also be generated by burning waste plant material. This means that in addition to crops the farm can create a net output of clean water and electricity. It is estimated the 150 of these farms could feed the whole of New York. Vertical farms also have a number of other benefits over conventional farms: -

  • Vertical farms are not effected by droughts, flood or other adverse conditions.
  • Different floors can be simulate different seasons and skip winter allowing an ongoing production of food all year round and multiple harvests per year for each floor.
  • Vertical farms can isolate crops from diseases and pests allowing for easier organic farming.
  • Vertical farms recycle all waste meaning there is no sewage run off.
  • Vertical farms do not use tractors or combine harvesters and can be placed in major population centres where the fodd is needed dramatically reducing the carbon footprint for crop production.
  • Much of the millions of square miles of farmland around the world can be returned to their original wilderness and forest states allowing endangered species a chance at recovery and helping to stabilise the climate.





The task of replacing many conventional farms across the world with vertical farms and returning the existing farmland to nature is a task that could take many decades and be fraught with difficulty (not least of which is what the farms owners would say). However if we have the commitment needed to do it then the benefit to mankind and the natural world could be huge. Vertical farms have potential to help solve our problems with food production, climate change, endangered species and even conficts over resources. More info can be found here, here and here.

Lifestraw

It is sometimes the case that a truly simple invention can change the world (The bicycle, the compass, the telegraph). The Lifestraw may be such an idea. The Lifestraw designed by Danish innovator Torben Vestergaard Frandsen is straw shaped personal water purification device that allows a person to drink directly from a contaminated water source. The straw design is incredibly simple: -

  • The straw is made of high impact polystyrene and has a cord to be hung around the neck.
  • When water is sucked through the straw it passes through two meshes (100 micron then 15 micron) this removes particles and even clusters of bacteria.
  • The water then pases through iodine impregnated beads.
  • The water passes into an empty chamber where the iodine can continue to kill bacteria.
  • Finally the water passes through a charcoal filter removing any remaining particles as well as the iodine taste.
A diagram of the Lifestraw can be found here.

The straw costs between £3-4 and is capable of filtering enough water for 1 person for a year. Here is a picture: -



Surprisingly WaterAid have been critical of the device. Their points are as follows: -

  • Lifestraw will not save people the long journeys that are often required to gather water in third world countries.
  • Lifestraw will not provide solutions to sanitation or irrigation.
  • For £15 water aid can supply a person with clean water for life.
I agree with all of these points, Lifestraw is not the final solution to the third world's water problems. But it can still save millions of lives. Half the people in the developing world are sick with a water borne disease which kill over 6000 people every day. I believe that in refugee camps, natural disasters and villages where NGO's such as WaterAid, Oxfam, and Practical Action have yet to complete water projects the Lifestraw can bring immediate relief from water borne diseases. Find out more here.