This tower's design was patented in 2010.
It takes about 40wh to power each tower, equivalent to powering a small light bulb. To produce 1kg of vegetables, it uses 5 cents of electricity and 12 litres of water.
Depending on the crop variety, each tower can produce 50kg to more than 100kg of greens for every growing cycle, or up to one tonne per year. That translates to an annual yield of up to 800 tonnes per hectare.
Currently, there are 800 such towers on its 3.65ha farm – about the size of five football fields – which has the capacity to hold up to 2,000 towers.
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