Future Cities Singapore

Urban farming looking up in Singapore

Editor’s Note: Future Cities: Singapore focuses on the exceptionally forward-looking urban approach of the island nation, to learn about the challenges of planning for future generations.

CNN  — 

Less than 20 miles from Singapore’s skyscrapers is a completely different set of high-rise towers.

Much smaller in scale but with a big ambition, over 100 nine-meter tall towers at Sky Greens vertical farm offer a new vision of urban sustainability.

Green vegetables like bak choi and Chinese cabbage are grown, stacked in greenhouses, and sold at local supermarkets.

The idea of vertical farming goes back to the 1950s, but Jack Ng, farm owner and inventor of the system in place at Sky Greens, has patented elements of his design.

Slowly rotating on water-powered, aluminum A-frames, the vegetables pass through a trough of water every eight hours. The water powering the frames is recycled and filtered before returning to the plants. All organic waste on the farm is composted and reused.

“The plants don’t get overstressed under the sun… at the same time they can get nutrients in the water equally,” says Ng.

According to Ng the energy needed to power one A-frame is the equivalent of illuminating just one 60-watt light bulb.

The farm’s first prototype was built in 2009 and since 2012 the fully operating farm has been supplying one of city’s supermarkets with weekly deliveries of its greens. The Sky Greens produce costs around 40% more than an imported Chinese equivalent.

Singapore only produces around 7% of the vegetables it consumes. While Ng believes that an expansion of its system of vertical farming could increase that to 50%, food security is less of an immediate benefit than the reduction of “food miles.”