A new method of growing food tackles large-scale problems like hunger, malnutrition and global warming.
Even though humans have grown food for 12,000 years, there is still a lot of room for improvement. One hundred thousand people die of malnutrition every day, and the United Nations estimates the world will have another 2.4 billion mouths to feed by 2050.
Roughly 80 percent of land suitable for farming is already in use and large-scale agriculture contributes to deforestation, pollution, aquifer depletion and climate change. Plants are surprisingly inefficient, using just 3 to 6 percent of sunlight for photosynthesis.
According to a small but growing cadre of greenhouse geeks, the solution is to start using high-tech facilities called vertical farms. In these tall indoor greenhouses, farmers grow crops in stacked beds, often hydroponically (using water instead of soil), and control every possible variable — light, water, temperature, nutrients — to minute degrees.
The idea of vertical farming crystallized in 1999 at Columbia University in New York, where ecologist Dickson Despommier challenged a class of graduate students to solve the inherent dilemma of agriculture: How to reduce the heavy carbon footprint involved in transporting countryside farm crops to growing cities.
“Making [vertical farming] happen could require the kind of technical expertise needed for, say, rocket science or brain surgery,” Despommier wrote in the resulting book, The Vertical Farm: Feeding the World in the 21st Century. “Then again, human beings do rocket science and brain surgery quite well.”
To function effectively, facilities need to be several stories tall and use natural or artificial light, or a combination of the two. In these sealed buildings, farmers don’t need to use pesticides or herbicides to protect the crops.
The outcome is a locavore’s dream: Professionals growing organic crops year-round in the heart of urban centers. With every detail über-optimized, yields can be extraordinarily high – as much as 30 times those of traditional farms.
Sky Greens, the world’s first commercial vertical farm, opened in Singapore in 2012. The facility’s 30-foot-tall towers produce lettuce, spinach and Chinese cabbage using rotating tiers of growing troughs.
The following year, FarmedHere opened in a 90,000-square-foot abandoned warehouse outside of Chicago. The farm reuses 97 percent of fresh water to grow arugula, kale, basil and mint, sold in more than 400 nearby grocery stores.
In Japan, Mirai operates the world’s largest vertical farm in a giant semiconductor factory that was abandoned after the 2011 earthquake. Compared to outdoor fields, Mirai produces 100 times more vegetables per square foot and uses 99 percent less water.
Thousands of vertical farms are already in operation, primarily in crowded countries such as South Korea, Japan, China and the Netherlands. In the U.S., new facilities are planned for Newark, New Jersey and Jackson, Wyoming.
“There’s no plant on earth that couldn’t be grown on a vertical farm, even the biggest fruit trees or root crops,” he said, adding that the technology is still in its infancy.
Farmers and companies are still working to solve a number of challenges.
Vertical farms eat more energy than traditional greenhouses thanks to more elaborate lighting, heating and power systems.
Vertical farms located in urban areas cut down on CO2 use because farmers don’t need to transport the food from faraway rural lands, but some designs require additional CO2 to be pumped in to stimulate plant growth.
Plus, urban real estate is expensive.
There’s also the question of whether consumers who cringe at GMO foods will eat plants grown in what are essentially laboratories.
“You would think, if it doesn’t have sunlight, it can’t possibly be nutritious, but the reality [is that] plants only harvest 10% of the sun’s rays, which we can recreate in the lab,” Harper told Fast Company.
“There is absolutely no nutritional difference between plants grown in sunlight and under an LED,” he said.
One of the greatest technical challenges facing the industry is the high cost of artificial lighting. The fluorescent lights that many vertical farms currently use, while relatively inexpensive, require lots of electricity.
That’s why some facilities, such as FarmedHere, have been converting to more efficient LED lights.
Prices for LEDs are dropping steadily, and companies such as General Electric and Philips have entered the game.
Mirai contracted GE to develop a custom lighting system using 17,500 LED bulbs that provide the exact wavelengths its crops need to thrive. The setup reduced power consumption by 40 percent and increased yields by 50 percent.
Researchers hope that organic LEDs, in which a film of organic compound provides the glow, will eventually become an even more economical and efficient option.
The idea of increasing agricultural efficiency applies to traditional greenhouses as well, said Adam Burns of Intel’s Intelligent Solutions Division. His group uses off-the-shelf Intel technology to help make greenhouses in China more productive.
Monitoring systems collect data and help managers make on-the-spot decisions to optimize things such as temperature and humidity levels.
“They can keep honing in and produce better and better results,” Burns said. He believes that using the Internet of Things (IoT) can help solve big problems like the fact that 25 to 40 percent of food produced worldwide is wasted.
Despommier said when he first started talking about vertical farming, he had no idea it would catch on the way it has. Now, as an industry leader, he is pushing for more crop diversity: root vegetables, grains, more fruits and herbs.
Does he think vertical farming has the potential to change the world?
“Man, I hope so,” he said.