Thirty-three meters under the streets of central London is an old World War II bomb shelter that’s been transformed into a hi-tech underground farm.
The long tunnels beneath Clapham are being filled with stacked layers of hydroponic beds - forming "vertical farms" - for growing salads and herbs that can be delivered to tables in the city within four hours of harvesting.
The growing system uses energy-efficient LEDs instead of sun, no pesticides, needs 70 percent less water than growing plants in open fields, and less energy than a greenhouse.
“The whole system runs automatically, with an environmental computer controlling the lighting, temperature, nutrients and air flow,” explains Steven Dring, co-founder of the company behind the operation, Zero Carbon Food.
The subterranean farm is optimized for growing crops like pea shoots, coriander, mustard leaf, rocket, radish and garlic chive: small, leafy greens with a short growth cycle – made even shorter through careful manipulation of the environment. Unlike outdoor fields at the mercy of variable weather, Zero Carbon Food can deliver a consistent product all year round. (A consistency that attracted at least one inquiry from an entrepreneurial druglord seeking a discreet cannabis farm).
The plants are picked and packed by hand in another part of the tunnel before distribution to restaurants, caterers and retailers under the brand Growing Underground. It’s already partnered with hyper-local food delivery company Farmdrop and is in discussions with supermarket Whole Foods.
The startup has the support of two-Michelin-starred chef Michel Roux, who is excited by the prospect of growing specific ingredients for his restaurants on-demand.
“When I first met these guys I thought they were absolutely crazy, but the market for this is huge,” said Roux when the company launched in 2014.
Zero Carbon Food has since raised around 750,000 pounds ($1.15 million) seed investment round through a combination of crowdfunding through CrowdCube and from G’s Fresh, which supplies salads and vegetables to M&S, Waitrose, Florette and Sainsbury’s.
With the current equipment – around a quarter of the kit required for maximum capacity in the tunnels - Zero Carbon Food can produce between 5,000 kilograms and 20,000 kilograms of crops per year, depending on the species, delivering an estimated turnover of 1.3 million pounds, says Dring.
Growing produce in urban areas takes some of the strain off the rural environment as demand for food increases in line with the burgeoning population.
“We’ve got to utilize the spaces we’ve got. There’s a finite amount of land and we can grow salads and herbs – which start losing flavor and quality as soon as you cut them - in warehouses and rooftops in cities near the people who will eat them,” he adds. “Use the rural land for things like carrots, potatoes and livestock.”
The chief executive of Zero Carbon Food's main competitor, Grow Up, agrees. “It's about making better decisions about what we grow where. The more salad you can grow in vertical urban farms, the more fields you have for cows,” says Kate Hofman.
Aquaponics and Aeroponics
GrowUp uses aquaponics instead of hydroponics in its vertical farm in a warehouse in Beckton, East London. Aquaponics grows plants in the nutrient-rich wastewater from fish farming. The closed-loop system delivers two products: Tilapia fish and salad. Every 20,000 kilograms of salad comes with 4,000 kilograms of fish.
“Apart from us and Zero Carbon Food, nobody else really demonstrating urban farming at commercial scale in London,” Hofman explains.
Even at this commercial scale, the combined farming space of GrowUp and Zero Carbon food is less than 2,000 square meters or 0.2 hectares - a tiny fraction of the 9,600 hectares of land used in the U.K. to grow salads for British consumption.
“But the growing season is really only between March and October. Outside of those months, everything is imported. We can provide a year-round supply of U.K.-grown produce,” says Hofman.
In the U.S., Aerofarms has built the world’s largest indoor farm inside a huge warehouse in Newark, New Jersey, which uses a mist of water and nutrients instead of submerging roots. Launching in November 2015, at full capacity the facility will produce around 1,000 tons of baby leaves and greens per year.
“We can already compete on price with the field farmer, but more importantly we take all the volatility out of the equation,” says Aerofarm’s chief marketing officer, Marc Oshima, referring to unpredictable weather and pest conditions.
“Global macro issues such as the increase in population, increase in urbanization, pressures on arable land and water supplies are at play. What we do out on the field is not sustainable,” he adds.