Yes, Dubai is at it again! The next challenging and seemingly unfeasible project to add to the skyline is a vertical farm that uses seawater to cool and humidify greenhouses and to convert sufficient humidity back in to fresh water to irrigate the crops.
This concept, proposed by the Italian firm, Studiomobile, was developed from the idea that the world's population continues to grow just as the available arable land continues to be deforested causing global warming. So with minimal farm land, the only other option is to build farms vertically and where better to test this than in Dubai.
The vertical farm features a soaring spire with pod-like ‘sky-gardens’ branching off to give it an organic feel in keeping with designers aims to create a clean, green, sustainable source of food for a more self-sufficient Dubai. The concept makes use of the Seawater Greenhouse process, which uses seawater to cool and humidify the air that ventilates the greenhouse and sunlight to distill fresh water from seawater to enable the year round cultivation of high value crops that would otherwise be difficult or impossible to grow in hot, arid regions such as Dubai. This is in stark contrast to costly and energy intensive desalination plants that rely on boiling and pumping to produce fresh water.
The concept works by continually cycling through three phases. In the first phase the air going into the greenhouse is first cooled and humidified by seawater, which is trickled over the first evaporator to provide a fresh and humid climate for the crops. Then in the second phase as the air leaves the growing area it passes through the second evaporator, which has seawater flowing over it. The humid air mixes with the warm dry air of the ceiling interspace making the air much hotter and more humid. The third and final phase sees the warm air forced upward by the temperature induced stack effect. In the central chimney the warm and humid air condenses when it comes in contact with plastic tubes that contain cool seawater. The drops of fresh water that appear on the surface of the condenser fall into a collection tank to be used to water the crops and for other uses.
The idea of vertical farming in the absence of farm land is a pretty good idea and I would like to see more details on just how this could be achieved. Nonetheless, I am not impressed with Dubai undertaking this project. If they had focused a bit more in the past on farming and actually trying to grow some crops for themselves instead of building on every available scrap of land and even creating more land for construction to cater to tourists, they might have had space to farm like "regular folk." If one of those ridiculous man-made continents had been dedicated to producing some cash crop, then maybe their economy would be in better shape than it is. So I guess now that building all manner of absurd highrises has failed, they want to try something new. I think this is more for the publicity and rep than for actual need.
Image obtained from: www.gizmag.com
For more info, check: www.treehugger.com/files/2009/03/vertica-farm-dubai-seawater.php