Sky Greens vertical farming technology commercialised in Singapore
On just 5.5 sqm one of the Sky Green towers can grow 2,500 plants and water usage is only 10% of the amount used in conventional farming with the same number of plants.
Whilst traveling through Singapore on my Nuffield Global Focus program, we were given the opportunity to visit Sky Greens in Singapore which was the first model applicable to my study.
The concept presented was clever and simple. There was a growing system that reached nine metres high on an A frame that acted like the vertical framework holding channels of water where the Asian vegetables were grown. The channels with the plants are filled with water when positioned at the bottom of the A frame, as the water fills the channel gravity forces it down under the structure, which moves the entire carousel allowing the plants to rotate and get an even amount of sunlight throughout the day.
In the picture shown to the left you can see the Asian vegetables that are growing in the channels. Styrofoam is placed on top of the growing pot to reduce moisture and provide consistent spacing for plants.
Sky Greens was started in 2011 with $100,000 of seed capital from the Singapore government and last year entered into a joint venture with a Chinese company, Charon Pokhand. Sky Greens is now investing $26m into expanding the Singapore operation and new systems in Thailand and China.
The Singapore expansion will increase the operation to 2,000 towers positioned on 3.7 hectares producing 8 to 9 million plants per annum.
My SWOT analysis of this system
- Is able to deliver 4,500 units per sqm per year in comparison to 600 units per annum with conventional farming methods
- Can be deployed on any surface and utilise minimal space
- Each tower only uses 1/2 a horse power of energy / 40 watts of energy
- Low water usage 12/L per Kg produced
- Is a commercialised farm in Singapore
- Highly capital intensive, 7-8 years ROI on a 10 year depreciating asset
- Singapore has a latitude of 1.35 degrees North which positions the sun high in the sky, with some of worlds longest sunlight days. Once you move this system further from the equator the operators will need to start compensating for light levels as the current system provides an average 2 hours a day of sunlight. On a system that already has a long ROI this would increase further.
- Plant quality was not great and in Singapore they were only growing 4 to 5 different varieties of Asian vegetables and lettuce, which didn’t really provide an accurate proof of concept for the broader range Leafy greens.
- Removing humidity and creating a healthy airflow so plants can transpire and translocate minerals would be challenging and would need further investments in energy to aid airflow / air extraction.
- The internal greenhouse logistics / people and material movement were not really considered and would restrict fluid and scalable workflow.
- Coming up with a concept that can redistribute the natural energy source of the sun to allow plants to have more then 2 hours of sunlight would increase plant growth and health
- Low light crops tolerant to higher humidity would make this system highly successful
- Growing crops in Urban locations, such as car parks and on top of shopping centres and many urbanised areas
- Local planning restrictions to build higher than 9m structures
- Disease from not being able to manage humidity and airflow
- Assets seem to be deteriorating faster then the 10 year depreciation period
- Labour cost increases due to the lack of overall internal logistics
I think that Sky Greens has a great commercialised system that will work well in areas close to the equator. It is certainly a forward thinking approach to agricultural farming. If you would like to read more information, please visit the company website: www.skygreens.com.