Dozens of feet below ground might not seem like the best place to cultivate plants, considering the lack of sunlight, but a small yet growing number of entrepreneurs are exploring subterranean sites for potential farms.
Columbia University professor Dickson Despommier kickstarted scientific, agricultural, technological, architectural, and even political interest in futuristic growing techniques with his 2010 book “The Vertical Farm.” In the years since, vertical farming, which increases growing efficiency by stacking rows of plants in greenhouses under LED lights, has flourished as an industry.
Many of the world’s major cities have their own iterations of vertical farms, and companies are sinking millions of dollars into research and development for large-scale hydroponic and aeroponic vertical farms that could produce far greater crop yields than traditional farming — year-round. Some projections value the industry at nearly $10 billion by 2025, up from only $400 million in 2013. To put that in perspective, the agriculture industry as a whole is estimated at a couple trillion dollars globally.
Vertical farming is a small part of the big, complicated picture of revitalizing the world’s food systems. But what if instead of reaching higher, these farms headed underground? Some businesses are exploring underground sites for farms, from abandoned London tunnels to limestone mines in Pennsylvania, from newspaper archives in Sweden to coal mines in Wales.
“At some stage, yes, I do see this completely replacing field agriculture,” said Steve Dring, co-founder of the London-based farm Growing Underground. “But I’m talking generations down the line. It’ll be complementary for now as the transition takes place.”
Dring founded Growing Underground with Richard Ballard in a World War II-era section of London’s tunnels in 2013, about 100 feet below ground. It’s poised for expansion within the U.K. within the next 24 months and is currently scouting sites and running feasibility studies on potential sites both above and below-ground in Europe, China, the Middle East and the United States.
“At some stage, yes, I do see this completely replacing field agriculture,” said Steve Dring, co-founder of the London-based farm Growing Underground. “But I’m talking generations down the line. It’ll be complimentary for now as the transition takes place.”
Why take up subterranean farming? “We’ve realized the degree and precision we can bring to controlling that environment is significantly increased by being underground,” Dring explained. Above-ground temperature fluctuations make it difficult to maintain the level of control needed to grow 365 days a year. Underground, the temperature and humidity remain largely constant, vastly reducing the energy needed to heat and cool the growing space. Dring also cites challenges with topsoil management, climate change, and an additional 2 billion mouths to feed by 2050 as the impetus for the project. “Ten billion people on the planet in 2050 and current farming under threat already? That’s the real driver behind all of this.”
Tim Davis, a board member at Hydroponic Farms USA, an above-ground hydroponic farm being built on reclaimed coal land in Kentucky, said that increased awareness of food safety is also a factor, as well as proximity to grocery stores. “When I go to the grocery store even in the summer, most bell peppers come from Holland, Israel, Honduras, and Canada and Mexico are the major countries that are providing bell peppers in the summer,” he said. “We’re going to grow them right here.”
Another driver is the low cost of some underground facilities and the falling price of LED lights. In Western Pennsylvania, a former limestone mine is currently being tested as a potential farm location. “We’ve spent a total of $140 so far,” said Daniel Bruce, the owner of Brady’s Bend Underground Storage, a vast network of tunnels more than 600 miles long. Bruce is working with Chatham University in Pittsburgh to test a small section of the tunnels for growing potential. He plans to start with salad greens and will know by December whether the conditions will be suitable for growing. “We’re playing with amounts, figuring out heat and air circulation requirements, will we need extra carbon dioxide,” he said. “If nothing else, I’ll have some delicious dinners.” Bruce estimated the mine has anywhere from 5 million to 10 million square feet that could potentially be devoted to underground vertical hydroponic growing, as well as the land above the mine. “Realistically, space is unlimited.”
On a smaller scale, Farm.One grows specialty produce underneath the two Michelin-starred restaurant Atera in New York City. Farm.One, also poised for growth in multiple cities, serves high-end New York restaurants ranging from Ai Fiori to The Dutch. The farm grows between 50 to 100 different varieties of crops at a time, depending on demand, and prices its produce on the high end, around $40 for a pound of basil, because of the high quality.
“There’s a lot of talk about sustainability, but it’s important to remember that growing produce underground using LED lights uses far more electricity than being outdoors,” said Farm.One founder Rob Laing, a former software engineer. “It’s actually not better for the climate to do this indoors,” he continued, adding that Farm.One buys renewable energy.
How climate change will affect the agricultural business is top of mind for many, especially given that a significant amount of the world’s carbon emissions occur in the agriculture sector (even excluding the belching cows). While heading underground may protect produce from climate change and require less energy than above-ground greenhouses, vertical farming and farming don’t lessen the energy requirements of producing food.
Reduced shipping emissions might mitigate this — if the farms are closer to urban populations — and the efficiency and consistency of vertical farming and growing underground can’t be overstated. “This recreates acres and acres of farmland in a small, controlled space,” Dring said, citing pea shoots as an example. Farming pea shoots in a field might yield three crops in a year and require a significant amount of land and water, he said. In a greenhouse, farmers can grow about 25 crops.
Growing Underground can produce up to 62 crops a year due to how much control it has over the environment. “We use reusable energy, solar and wind,” Dring said. “From a sustainability point of view, we’re using more energy, but we’re using sustainable sources….We’re also progressing toward onsite energy generation and closing the loop.”
Who’s buying crops grown underground? There has been some pushback from farmers with current retail contracts with grocery stores and suppliers, but by and large, the underground farms are plugging into existing market models. “This is a bold step away from a supply chain that’s been in place for many years,” Dring said.
And, speaking of bold growth, the next step for these farms after expansion will be automation. The systems are headed for the point where humans will pop in a seed at one end and take the produce out at the other without any contact in between. “Field farming has had decades of automation,” Laing said. “Indoor farming is catching up, but it’ll take a huge amount of investment to get to that point. The noise is definitely rising, though.”
Jeremy Reynolds is the classical music critic for the Pittsburgh Post-Gazette. His work is supported by a grant from the San Francisco Conservatory of Music, Getty Foundation, and Rubin Institute.