In the 2015 Matt Damon movie The Martian, based on Andy Weir’s 2011 novel of the same name, an astronaut awaiting rescue on Mars subsists for months on potatoes he grows in his habitat.
“I think I read [the book] in three nights,” says Neil Mattson, associate professor at the School of Integrative Plant Science at Cornell University. He says everyone in his field is a big fan.
And no wonder: Mattson and his colleagues have been advancing the field, or lack thereof, of controlled environment agriculture (CEA) for decades—that means farming indoors, whether in a greenhouse or entirely under grow lights. Just like Matt Damon’s character in The Martian, Mark Watney, these researchers and their commercial partners have been perfecting the right mix of nutrients, water, lighting, and environmental controls to grow fruits and vegetables untainted by pesticides, contaminates, or even outside air. It lets urban farmers do more with less real estate by growing up—as in stacking planting containers in a style of CEA known as vertical farming.
Now not only science fiction but reality has caught up with them as commercial ventures take off. Spurred by the COVID-19 pandemic, CEA has experienced healthy investment in startups trying to shorten supply chains that stretch miles or even around the world for groceries. This means fresher food for consumers and less food going bad, thereby reducing food waste, which is one of the top contributors to greenhouse gas emissions, according to Project Drawdown.
Fresher Food, Closer
The appeal of CEA and vertical farming is clear: fresh-picked fruits and veggies available within a few miles, or even at the point of sale. For example, CEA company Kalera—soon to open new facilities in Atlanta, Denver, and Houston—reports its indoor urban farms yield up to 400 times more produce than conventional farms covering the same ground. The company, which has raised about $150 million, also boasts of distribution under 50 miles from the farm.
Like many of the latest crop of CEA startups, Kalera practices vertical farming, which Cristian Toma, chief science officer and co-founder of Kalera, believes is a “newer approach.” Though other companies have long practiced CEA in greenhouses—Gotham Greens, for instance, started commercial operations in 2011 and runs greenhouses in such places as atop the Method soap factory on Chicago’s South Side—vertical farming goes a step further by relying solely on artificial light.
The primary advantages of vertical farming include the year-round production capability of greenhouses and stacked plantings that extend the growing space vertically, as well as horizontally, for urban agriculture that’s consumed as close to the source as possible. Greenhouses and vertical farms each conserve water while keeping crops out of the elements—both increasingly important benefits, explains Kalera CEO Daniel Malechuk. “We’re seeing that climate change is certainly having effects on traditional growing cycles,” he says. “And it’s going to continue to become more and more important to conserve water in the future.”
But there are some caveats, say the experts. For starters, CEA is more expensive than conventional farming due to higher energy costs related to lighting and climate control, says Mattson. That means growers must focus on higher-value crops such as herbs and salad greens to justify the investment in climate-controlled facilities. It also means they tend not to grow cheaper staples such as rice, potatoes, and corn, which is among one of the crops that presents a particular challenge to vertical farming due to its height. “You need something that grows quickly and can get many harvests per year, like lettuce every 30 days,” says Gene Giacomelli, professor of biosystems engineering at the University of Arizona. That means CEA’s impact on food deserts and food insecurity due to supply chain issues is limited, at least for now.
Nor is there currently a direct carbon benefit, according to a chapter in Food Supply Chains in Cities, co-authored by Mattson. “Growing in a greenhouse in New York City, we had about the same carbon footprint and energy use as growing in a field in California and shipping 3,000 miles,” he says. “In a warehouse farm, it was about two-and-a-half times more.”
“Growing in a greenhouse in New York City, we had about the same carbon footprint and energy use as growing in a field in California and shipping 3,000 miles. In a warehouse farm, it was about two-and-a-half times more.”
–Neil Mattson, associate professor of Integrative Plant Science, Cornell University
But CEA farmers are working hard to lower energy costs and reduce their carbon footprint. “This is a priority for the industry,” Mattson says. “We have seen [farmers] reduce their carbon footprint by installing cogeneration systems—using natural gas to produce the electricity they need, waste-heat used for heating the greenhouse, and CO2 from the exhaust captured and used to enhance plant growth.” Kalera and other operators also purchase renewable energy credits to offset carbon emissions through solar and wind energy production, Toma and Mattson confirm.
Even now, the benefits to consumers outweigh the cons compared to conventional farming, Malechuk believes. “There’s nothing quite like having a local product that’s clean, fresh, and sustainable, [availble] only hours since it’s been harvested.”
Bringing the Farm Home
CEA also has the potential to provide more reliable and less strenuous jobs than conventional farming, according to Giacomelli. “Greenhouses, and now vertical farms, can take a grower of plants and remove them from the open field, which has unpredictable weather that forces them to be out in the hot sun [in the summer] and/or harvesting certain crops in the cold of winter.” Plus, it’s a year-round job, and one that didn’t exist in an urban setting. Toma says each Kalera facility employs 60-70 people, including horticulturalists, harvesting and packaging specialists, maintenance personnel, office workers, quality checkers, and managers.
The cost-benefit should improve over time with advances in technology. Already, machine-learning algorithms, advanced sensors, and more efficient LED lighting have increased production and quality, according to Murat Kacira, director of the Controlled Environment Agriculture Center at the University of Arizona. For example, artificial intelligence can improve crop yields by tweaking environmental factors based on data about past growth and conditions. “The cost of these systems has been decreasing,” says Kacira.
Even individual consumers can get in on the action with CEA kits from companies such as AeroGarden and Lettuce Grow. Users just provide water. Prepackaged seed pods and nutrients, and built-in LED lighting do the rest.
Mark Watney, eat your heart out.