Sky Greens opened on October 12, 2012 and claims to be the first economically viable vertical farm in the world. Sky Greens started as a 3.2-acre-collection of 100 three-story glass towers housing racks of Chinese cabbages, bak choi, and other leafy green vegetables.
As of August 2014, it has grown to 600 towers. The driving force behind the initiative is entrepreneur Jack Ng. Ng, an engineer by training, put his mind to making the amazing system detailed in the image below.
Ng claims that he fields ¼ the operating costs of a traditional farm in Singapore. Energy comes from a gravity-powered water wheel and a closed loop hydraulic system. These savings don’t just come from his efficient design, but the farm’s proximity to market reduces transportation and fuel costs as well.
Not only has he cut costs, but Ng has increased efficiency. Sky Greens estimates that it is somewhere between 5 and 10 times more productive per unit of area compared to traditional farms in Singapore. Ng’s product has also earned a higher price point than competing imports (currently 5-10% more expensive than local greens, a significantly lower percentage than the 40% cost discrepancy of his 2009 prototype).
Ng’s towers produce more and even use less energy. The efficient design optimizes natural light usage and Sky Greens only spent an estimated $360/month ($3/tower) on electricity for its original 100 towers. Ng also lowers input costs by recycling water and nutrients.
Despite the price difference between Sky Greens’ produce and imports, people in Singapore have responded positively to the fresh, local vegetables. It takes just three hours from harvest for Sky Greens produce to hit the shelves. On the other hand, imported vegetables take three days to three weeks says Eco-Business.
Sky Greens has been successful enough that Ng plans to build to 2,000 towers in the coming years, bringing the total cost of the project to $28 million (USD), according to Eco-Business.
Additionally, interested parties, like local farmers, can also buy the smaller versions of the towers (2m-by-3m) for $15,000. It is worth noting that though by now these towers are a tried and tested model, they do not even begin to compete in price to some of the other personal growing units on the market.
Knowing this, and knowing that Sky Greens’ 200 gram bag of xiao bai cai retails for $1.25, the Urban Vertical Project has made some very, very rough calculations (Thank you to Eco-Business and Reuters for the data that is out there).
With 600 towers producing a ton/day, assuming that the only product was full retail xiao bai cai, Sky Greens grosses $2,281,250/year.
Knowing the cost to build 2000 towers is an estimated 28 million, we find that 600 towers costs S11.4 million. Energy costs top off at just under $26 thousand dollars each year. Notably missing from the cost side of these estimates are labor, materials,original R&D, and upkeep.
However, with just these numbers, we find that Sky Greens starts making a positive return on investment somewhere in its 5th year of operation. Though a flawed metric for a number of reasons, that sounds like a winning proposition to me. (Let me know in the comments if you’d like to see the full calculations written out or if you have more data to add)