Vertical farming rising to meet food needs

Aloha, food fans! The population on this planet has more than tripled over the last seventy years, and is projected to reach 10 billion folks by 2050, of which 80 percent will be living in urban areas. The Food and Agricultural Organization of the United Nations (FAO) projects that food production will have to increase by 70 percent over the same time frame to feed our world’s population.

Traditional farms are being pushed farther out from centers where people live and buy food. Traditional field farming already consumes more than 80 percent of earth’s arable (farmable) land, contributes 70 percent of the contamination to our fresh water, and consumes 70 percent of earth’s fresh water, of which 50-80 percent is lost to evaporation and runoff.

Anybody interested in vertical farming? Compared with traditional field farms, vertical farms use 75-95 percent less water, produce between 10-390 times more crop yield per square footprint (you read that right), and can produce crops in half the time.

As an example, Singapore imports over 90 percent of its food. Sound familiar? One enterprising engineer there developed an elegantly simple low carbon hydraulically-driven method of rotating trays of plants vertically around an A-shaped tower, like a Ferris wheel. Jack Ng’s design uses the energy equivalent of a 40-watt bulb per tower, and has won international recognition and awards.

In his inauguration speech after being sworn in for his second term this past December, our Governor Ige called for a sustainable and self-sufficient Hawaii “…whether we are talking about food or energy production.” Doubling local food production by 2030 is one of his administration’s goals, and Hawaii was the first state in the nation to enact legislation setting a 100 percent renewable energy goal.

Hawaii’s first indoor vertical farm was started in Kaka‘ako by Kerry Kakazu in 2014. His 800 sq.ft. MetroGrow Hawaii operation produces about 100 heads of lettuce a week and a couple dozen containers of microgreens for his clients, which include fifteen high-end restaurants, and medicinal plants for an herbology store. He recently renovated another 2,000sqft to expand his indoor vertical farming operation.

AeroFarms in Newark, NJ built their operation in a former paintball and laser tag arena, “…which boasts 30,000 square feet of growing space and some impressive spray paint work.”

Rather than sunlight, specialized LED lighting is used to grow the crops in stacks over thirty feet high. Instead of soil, the 250 kinds of greens are grown in reusable cloth made from recycled plastic, and use Ed Harwood’s aeroponic technology where the roots are misted with water and nutrients.

AeroFarms states this method allows them to use 95percent less water than traditional field farms, and that their yield is 390 times more crops per square foot. AeroFarms recently began growing in their ninth facility – a former 70,000sqft steel mill – to become the world’s largest indoor vertical farm.

Since 2009 the Paignton Zoo in the UK has used Verticrop’s hydroponic vertical farming system to grow food for their animals.

Their trays are suspended around towers which rotate and move on overhead tracks in a closed loop conveyor system. The top trays get the maximum sunlight, where the lower trays are exposed to different angles of the sun when rotating. Energy efficient LED lights are on standby to supplement waning natural light when necessary.

Back to Singapore, the third most densely populated country in the world.

The trays of plants at Sky Greens’ operation rotate vertically around each A-frame tower at 1mm per second, allowing all trays equal exposure to sun, with between four and ten revolutions per day depending on the tower heights.

This design allows for easier access to crops and harvesting than other vertical farming methods that I have found so far in my research.

All of these vertical farming methods are organic and use no pesticides or herbicides. They can reduce the “farm-to-fork” time to bring consumers fresher and more nutritious produce, and reduce the fossil fuel transportation costs. For more information, check out VerticalOnKauai.org.

•••

Susan Oakley is a resident of Kapaa.