The towering structures that fill urban skylines across the world could soon be filled with people and farm equipment. This is the dream of vertical farming.

Vertical farms can take a wide range of forms. The connecting feature of these innovative agriculture centers is their ability to grow food without using a lot of land. They accomplish this generally by growing food in stackable trays or on various growing levels within a vertical structure. While these growing centers can be built almost anywhere, many enthusiasts imagine them sprouting up in urban centers as either self-contained structures or even integrated into office and residential buildings.

Advanced vertical farm designs combine greenhouse agriculture, renewable energy, and hydroponics to provide cities locally based agriculture centers.

Elements of this futuristic vision are already a reality in the United States, the Middle East, Asia and Europe.

The birth of modern vertical farms

Ecologist and Columbia University Professor Dickson Despommier is most often credited with creating the modern vertical farm movement. After working on the concept for years, Despommier’s ideas entered the mainstream when he published The Vertical Farm Feeding the World in the 21st Century in 2011. This book helped fuel interest and development in vertical farms, but, as he explains in the video below, practical vertical farms are going to look more like complex greenhouses than the fantastical designs put forward by young innovators.

The argument for vertical farming

“The human population is expected to rise to at least 8.6 billion, requiring an additional 109 hectares to feed them using current technologies, or roughly the size of Brazil, Despommier said in an essay on vertical farming. “That quantity of additional arable land is simply not available.”

Despommier believes building up is the only solution.

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Other advocates of vertical farming cite a broader set of benefits, ranging from year-round production, to reduced pesticide use, to less pollution from shorter distribution lines when growing centers are located within the populations they feed.

It’s important to note that there are skeptics who refute Despommier’s claims that the planet is running out of usable farmland as well as the sustainability of vertical farms. Despite these objections, a global industry has developed around vertical farming.

How it works

Vertical farming must get creative to duplicate traditional agriculture in non-traditional spaces.

Companies use a wide range of solutions from rotating crops to face the sun (like the Sky Greens approach mentioned below), to reflecting sunlight onto each level of the farm, to special LED lighting systems that replace sunlight.

Vertical farming can actually create more food than traditional farming by growing food hydroponically.  This method uses substantially less water and, because it’s enclosed, is less vulnerable to bugs and disease. And soil alternatives like pumice make the growing environment much more flexible and efficient, as well as less ecologically damaging to set up.

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Does it work?

Vertical farms are already in use in a wide variety of places like the US, Oman, and Singapore. Current examples are more in the “advanced greenhouse” variety that Despommier referenced in his video, but there are a few companies putting more futuristic designs into practice.

Here’s a look at a few of the vertical farms already changing agriculture.

Podponics, (USA, Dubai, Oman)

The advanced greenhouse company, Podponics, started in Atlanta, Georgia, in the United States. Their system uses recycled shipping containers to create stackable, modular greenhouses. The company estimates each shipping container produces the same yield as an acre of traditional farmland. The company has raised millions in startup capital and runs projects in Atlanta, Dubai, and Oman.

Aerofarms (USA)

Image: Aerofarms

The world’s largest vertical farm is now located in Newark, NJ, in the United States. Startup Aerofarms converted a steel factory into a 69,000-square foot agriculture center that opened earlier this year.

The urban farm produces as much as 2-million pounds of leafy greens a year through a new growing system called “aeroponics,” which does not use direct sunlight or soil to deliver nutrients. It nourishes the plants with special LED lighting and delivers nutrients to plant roots through a liquid mist. The trays can be seen in the image below.

A photo posted by sustainPSU (@sustainpsu) on

Their lettuces are already available in stores across New Jersey.

A photo posted by @ckennylin on

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Plantagon (Sweden)

Image: Plantagon Mockup

A Swedish company, Plantagon, is one of the leaders in bringing agriculture into urban settings. The company sells conversion kits for existing buildings interested in adding greenhouse growing pods to their interior or exterior spaces. Next, the company intends to create the world’s first true “mixed use” building with both offices and agriculture centers in the same structure.

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The company currently runs a geodesic dome known as the “Plantscraper” in Linkoping, Sweden (pictured above). The dome has allowed the company to experiment with different technologies as they design their full mixed-use building also intended to be in Linkoping. In the video below, Plantagon outlines the vision for this first-of-its-kind space.

Sky Greens (Singapore)

Built by Sky Urban Solutions, the Sky Greens vertical farm is the “world’s first low-carbon, hydraulic-driven vertical farm,” according to its website. The farm’s major innovation is a system that rotates hydroponic trays so each is regularly exposed to natural sunlight, reducing the need for costly lighting systems.

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Sky Urban Solutions is planning a much larger urban agricultural initiative for the small island nation it calls home. The company wants to build the SG100 Agripolis, a farm and research center that could provide 30% of Singapore’s green leafy vegetable needs. The proposed project has the backing of Singapore’s government because it would promote national food security and resiliency. The video below provides an overview of the venture.

The future of farming

It’s not clear if vertical farming will save the planet, but the early international experiments do seem to show it will be part of the world’s agricultural systems.

Explainer

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