05.07.13 8:45 AM ET
Vertical Indoor Farms Are Growing in the U.S.
On average, food travels 1,500 miles to get from distant fields to the typical dinner table. In colder weather, that number can rise drastically, when stores have to fly produce like blueberries and tomatoes in from tropical locales like Mexico and Peru.
But the arugula and basil produced year around at FarmedHere, a farm that opened in March outside Chicago, never travels more than 25 miles to market. And because the greens are grown in an indoor, multi-level facility, they’re available all year round.
FarmedHere is considered the country’s largest indoor, vertical farm. And it is part of a growing international trend. From the world’s first commercial vertical farm in Singapore, which is expected to produce one ton of vegetables every other day, to the planned 12-story, conical Plantagon in Linkoping, Sweden, that will grow plants on conveyor belts, businessmen and farmers are increasingly latching onto the idea of indoor farming.
“You can do more with your square footage. If you have an acre of land you have an acre of land, but if you have an acre of land with four stories, you have four times the amount,” said Shelby Phillips, program manager at The Plant, a vertical farming space on Chicago’s South Side.
Typically placed in multi-storied buildings and warehouses, vertical farms use florescent lights to grow mostly leafy green crops and utilize manmade heat and air to control the atmospheric temperature. Not to be confused with greenhouses, these farms are distinctive for their reusing of resources and stacking of crops—sometimes several stories high.
At The Plant, workers turned a dilapidated three-story meat-processing factory into a working, USDA approved farm space. The 95,000 square foot “business incubator” is home to multiple small businesses. One third of the space is used for the non-profit Plant Chicago aquaponic farm.
Chives, herbs and leafy greens are grown in hydroponic systems that completely submerge plant roots in water without using soil. The plants get their nutrients from the water, which is continuously pumped between their roots and adjacent fish tanks full of tilapia. Their byproduct is used to organically fertilize the food, while the plants naturally clean the fish tanks. Both products, fish and vegetable, are later sold at farmers' markets.
The Plant currently has three, three-thousand gallon tanks housing nearly 18,000 fish and 3000 square feet of growing beds. The symbiotic relationship is part of what The Plant calls its closed-loop system.
“The same water stays in the system at the same time. One of the big benefits of aquaponics is the reduction of water consumption and efficient re-use of the water already in the system,” Phillips said.
Vertical farms are increasingly becoming viable options not just because of the resources they save, but also because of their production rates.
“What makes our vertical farms unique is our greater productivity,” said Marc Oshima, chief marketing officer at AeroFarms., an Ithaca, New York-based company that provides vertical farm technology for sale to other farms across the globe. “We have 30 times greater productivity per square foot and 6 times better productivity than a greenhouse.” Aerofarms’ technology utilizes aeroponic growing systems, in which plants roots are left exposed and watered through mist.
According to Oshima, farms using the Aero technology, including FarmedHere, can have up to 22 crop turns a year while conventional farms have 2 or 3.
Vertical farms also provide other boosts to efficiency. AeroFarms grow in the air so they utilize 93 percent less water than traditional farming and don’t contribute to hazardous run-off. In fact, most vertical farms don’t need pesticides at all, because they are grown indoors and therefore are certified organic.
One of AeroFarms sister farms in Saudi Arabia also utilizes a system where it takes the unused mist out of the air and recycles it, making up for a large portion of the farm’s overall water needs.
Critics worry that vertical farms may be convenient to cities, but that high-energy consumption from running grow lights ultimately balances out any environmental or monetary benefits from cutting out massive transportation costs. Also, people driving to farmers' markets to buy the vegetables may help put the fuels back into the system.
“Farm to store transportation accounts for less than 5 percent of food system greenhouse gas production because a truck full of tomatoes uses much less energy per tomato than a shopper driving to a farmers' market to buy a few veggies,” said R. Ford Denison, an adjunct professor of agricultural ecology at the University of Minnesota.
Yet, many vertical farms are aware of their energy consumption and are trying to integrate renewal energy systems and smart grids into production. “There’s not a question that lights are part of our big expense,” Oshima says of AeroFarms. “But our business model works, and we have very much to look forward to in terms of our philosophy for renewable energy.”
AeroFarms would ultimately like to be powered by anaerobic digesters that break down waste and capture the residual biogas to create electricity and heat.
The Plant is also in the middle of revamping its energy system. The farm plans to utilize an anaerobic digester to gather waste such as left-over plant roots to generate power. Once the digester is fully installed, The Plant hopes its annual yield of 5,000 tons of bio-waste will be successful in fully powering the system. Said Shelby Phillips: “That’s a sustainable model.”