The Only Way Is Up: Will Vertical Farms Tackle The World's Growing Food Crisis?
David Farquhar inside his vertical farm CREDIT: STUART NICOL/STUART NICOL PHOTOGRAPHY
15 AUGUST 2019
In an unassuming white shed on the outskirts of Dundee lies what could be the most futuristic farm in the world.
It’s not reached by trundling down miles of country roads, but by going through a pressurised air lock designed to keep the uncontrolled outside out.
And the crops - towering stacks of vegetables and fruit grown in metal trays under coloured LED lights - are not tended to by rugged farmers in overalls.
Instead they are overseen by robots, who carefully manage every environmental parameter: from light to temperature to CO2 to humidity, in a totally closed system without a handful of soil or ray of sunlight.
It might sound like a dystopian scene from science fiction, but this demonstration farm, run by Scottish technology firm Intelligent Growth Solutions (IGS), is not a vision of the future. It’s a look inside one of a growing number of indoor vertical farms sprouting up around the world in old factories, skyscrapers, warehouses and disused highway tunnels.
Plants grown under LED lighting CREDIT: STUART NICOL/STUART NICOL PHOTOGRAPHY
But why are we growing upwards rather than outwards? The answer lies mostly in our dwindling natural resources and growing population, particularly in Africa which is undergoing a youth boom.
According to the United Nations, by 2050 the amount of arable land per person could be one third of the amount that was available in 1970. The earth’s population meanwhile will have more than doubled to 10 billion in the same period.
While there’s still more land that could be brought under cultivation doing so would also mean destroying more forests and wild areas.
The farmland that is available is not evenly distributed. That’s why densely-packed places like New York, Hong Kong and Singapore are looking at farming upwards. It’s why China too, which has to feed one-fifth of the world’s population with one-tenth of its farmland, is turning to vertical farms.
The challenge is complicated by an increasingly unpredictable climate that can take out a crop in a matter of days.
“If you can have a system that’s independent of the climate, the weather and availability of land you’ve got a very disruptive new food supply system and that’s what indoor vertical farming can potentially do,” says Professor Colin Campbell of the James Hutton Institute, a Scottish research centre that works alongside IGS to build technology for vertical farms. “It takes the weather and puts it inside a box.”
But it is not cheap and it is why most vertical farms are currently in wealthy countries despite the fact that most of the additional people the planet will need to feed by 2050 will live in the developing world.
According to proponents of vertical farming such as David Farquhar, the serial entrepreneur who runs IGS, while the technology is still at the starting gate, the potential global environmental and societal benefits of vertical farming are huge.
“It can do a huge amount of good. You can help to feed people, improve the quality of produce people get, reduce food miles and reduce the use of chemicals,” he says.
Those in favour of vertical farms argue that if you keep pests and diseases locked out, there’s no need for pesticides and other toxic chemicals.
Vertical farms also use a fraction of the water of conventional farms. It takes just two to four litres of water to grow a kilogram of vegetables in a vertical farm compared to 16 litres in a Dutch greenhouse and 60 litres in a Mediterranean field.
By bringing food production to cities, close to where most of it is consumed, you avoid gas-guzzling transport. And by growing upwards, land is saved.
And the benefits are not just environmental. Taking out the variability of light, soil, rainfall and everything else that can’t be controlled outdoors, also takes out the variability out of the crop.
“All the plants are exactly the same height - there’s no wonky veg in there,” says Prof Campbell.
By experimenting with light scientists can change how a plant tastes and feels without any genetic modification.
“By changing the wavelength of light you can change the chemistry of the plant,” says Prof Campbell. “You can increase things like flavour and taste, and you can increase the concentration of health promoting chemicals.”
Others maintain however, that recreating nature indoors comes at a cost.
Andrew Jenkins, a researcher at Queen's University Belfast believes vertical farming has potential for countries like the UK that import a lot of food, but cautions that the current high energy costs of artificial lighting could outweigh the benefits.
“Growing crops that require four to five times the energy means we [in the UK] are in a worse position than with imports,” says Dr Jenkins.
A technician tends to plants in a vertical growing facility CREDIT: STUART NICOL
Vertical farming’s champions are nevertheless, confident that scientists are already cracking the energy question. Among them is Mr Farquhar, who says IGS’s technology has reduced the typical energy use in a vertical farm by 50 per cent.
Dickson Despommier, emeritus professor of microbiology and public health at Columbia University, is something of a vertical farm visionary. When he published his seminal book on the subject in 2010 there were no such farms in existence.
“Now everyone is into vertical farming,” says Prof Despommier.
Mr Farquhar agrees. He says there’s been more media interest in his vertical farm in the year since it launched than in all the other enterprises in his more than 25-year career in technology.
Leo Marcelis, an expert on indoor farms at Wageningen University in the Netherlands, agrees that interest in vertical farming is global but believes that the high cost is stopping the spread of the technology to poorer countries, where it is needed most.
“In developing countries, there’s a lot of interest in this but it’s too early for them as it’s a relatively expensive system,” says Prof Marcelis. “At the moment high investment and running costs will stop it expanding faster.”
Plants growing under LED lighting at the vertical farm in Dundee CREDIT: STUART NICOL
Although most interest in his technology is from richer countries Mr Farquhar says that in the last few weeks alone he has received inquiries from places including the Ghana, Botswana, Ethiopia and India.
Among the countries pursuing vertical farming with a vengeance is China where a 250-acre district of urban and vertical farms is being planned in Shanghai.
Africa is also growing and rapidly urbanising. Vertical farming advocate, Dr Esther Ngumbi, a Kenyan researcher at the University of Illinois, is pushing the idea of growing upwards in Africa - albeit with smaller, cheaper, lower tech versions that borrow some of the land and water saving principles from vertical farms in the wealthy world.
Although from the point of view of the science almost any crop could be grown in a vertical farm, it’s currently only cost-effective to grow leafy greens and herbs - light, high value crops that don’t need long periods of time under costly artificial lights to mature. They are also short enough to stack in many layers.
Given the energy costs, Prof Marcelis is doubtful that vertical farming will be used to grow the cheap, non-perishable crops such as corn, rice and wheat that form the bulk of our diets.
“I don’t think that staple crops will be grown. That’s just not economically feasible,” he says. “What we see most is fresh vegetables where there is an advantage of having it near consumers”.
Since the leafy greens and herbs on which most commercial vertical farms are focusing only make up a tiny proportion of our daily calorie needs, skeptics argue that such farms will play a limited role in meeting food security needs, particularly in poorer countries.
Others also question the claims that growing fresh produce near urban populations will make us healthier, even for those who can afford it. A recent study of indoor vertical farms in New York found that the typically grown crops of lettuce and basil did little to improve diets and nutritional intake.
Prof Marcelis is however, optimistic that more nutritious crops, even though lacking in calories, will eventually be grown in vertical farms. “More and more initiatives are coming up with growing tall crops like tomatoes and peppers that are grown over a long duration so we’ll see it gradually expanding,” he says.
One way vertical farms might be able to help produce energy dense staples is by allowing quicker production of better seedlings for things like potatoes.
According to Prof Campbell this is one way field agriculture and indoor vertical farms can work together. The Dundee facility is working on “speed breeding” better varieties of basic crops in half the time it would take outdoors.
“Conventional field agriculture will continue to be the main way to provide staple crops for the future but indoor vertical farming can help with that as you can use indoor vertical farms to mass propagate the plants you plant out in the field,” he says.
Growing efficiently indoors what’s grown inefficiently outdoors also frees up valuable land for things like rice and wheat, says Mr Farquhar.
“There’s a lot of land being used inefficiently at the moment. If we can bring that inside and make that land available for growing staple crops then surely that’s a good thing,” he says.
But growing fruit and vegetables indoors is not just a way of helping us grow more energy rich foods outdoors. For Prof Despommier indoor vertical farming is one of the keys to addressing climate change.
“Farming is the worst thing we’ve ever turned loose on nature,” he says. “If you grow your food indoors and grow your trees outdoors it slows down climate change.
“Farming outdoors is failing, so indoor farming has to succeed.”
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