Vertical Farms

This is an interesting and challenging idea. Vertical farms would potentially sustain large cities: as the world's population grows, land space used traditionally to farm could run out of productive soil and water. Moreover, deforestation etc which is a result of traditional farming (clearing space for farmland) leads to climate change. Vertical farms offer a solution to this: hydroponic methods can be used to grow upwards- saving space in cities, and there is far less waste.

http://www.verticalfarm.com/