Saturday, 4 February 2012

Does Vertical Farming Stack Up?


Since 1970 population growth has halved the amount of arable land per person to half an acre. By 2050 there will be an extra 3 billion people on the planet. Just providing their drinking water will reduce what is available for agriculture by 18%. Soil based farming will no longer be sustainable.
The future may well look something like the pilot project run by Valcent Products at Paignton Zoo. The farm  grows red chard, mizuna, mixed leaves, and a variety of herbs as well as edible flowers and fodder crops such as wheat grass and barley. Currently the farm imports a wide variety of veggies for their animal feed, so this provides a local, sustainable alternative for the zoo's residents. (click here for video)

The ‘farm’ requires just 5% of the water for field crops, produces 20 times the yield per acre, and can be built almost anywhere.
The growing operation works on a conveyor system, with automated loading of plant trays for harvesting and replanting. The whole set up has been designed for minimum maintenance, with computerized controls to regulate irrigation and water supply and the environment within the polytunnel. Valcent claim the farm will require one staff member working approximately two hours a day to keep it running, and could cut the zoo's feed bill by as much as £100,000.

Another benefit of this system is the fact that it can produce food very close to where it will be consumed. This means that food miles are minimised, that the food is fresher and loss through damage & spoilage during transport will be cut out. Better still, the use of pesticides, herbicides and fungicides can be kept to a bare minimum by growing plants indoors in a controlled environment. Soil erosion will not be a problem because the food will be grown hydroponically, recycling techniques will ensure that only a fraction of the amount of water and nutrients will be needed compared with conventional farming, and there will no problem with agricultural run-off.
Initially it is predicted that units with large catering operations like hospitals will all have their own vertical farm and supermarkets may well take up the idea if it is commercially (& politically) a success. Then, according to the UN’s Population Division, by 2050 around 70% of the world’s population will be living in urban areas. So it makes sense to move farms closer to where everyone will be living.

As technology progresses, skyscrapers with different floors of fruit and vegetables will be common place with a shop on the ground floor and crops harvested to order. Our current practice of shipping produce around the country (if not the World,) growing crop varieties for their longevity when picked rather than their taste & vitamin content, and washing & coating them in chemicals may one day seem totally bizarre.