Solviva Salad? Five-storey vertical farms? A taste of Peter Ladner's new book on growing food in cities.
Asked to create a concept for vertical farming in New York City, the architecture firm WorkAC designed this.
- The Urban Food Revolution: Changing the Way We Feed Cities
- Peter Ladner
- New Society Publishers (2011)
[Editor's note: The following chapter, "In Praise of Technology," is excerpted with permission from Peter Ladner's The Urban Food Revolution: Changing the Way We Feed Cities. The book is an essential resource for anyone who has lost confidence in the global industrial food system and wants practical advice on how to join the local food revolution.]
A week after the wettest September on record, farmer Bill Zylmans called into a local radio show from his tractor on his farm in Richmond, B.C. You could hear the resignation and despondency in his voice:
"I'm sitting here on the tractor, looking out over the fields. Unbelievably I'm in the first of 18 fields I'll be able to finish harvesting today and this 12-acre field is the only one I'll actually be able to get the whole crop off. At this time of the year, we just don't have the sun to dissipate the water into the air, and the soil is so saturated from all the rains we've had in September. Remember we had the 50 millimetres [2 inches] of rain on Aug. 31. We just have never been able to recover from that. The only thing that has happened is that as we moved into October, the crops are deteriorating every day.
"It's not just potatoes. It's cabbages. It's broccoli. It's brussels sprouts. It's cauliflower. It's corn. It's beans. It's carrots. It's beets. Right through the whole library of fresh vegetables that everyone will want to enjoy on this Thanksgiving.
"Farmers have been trying. They've been going to the high spot of their fields, taking risks, taking chances, trying to rescue a few potatoes here and there. It's all but over. Even the high places on the fields, you just don't have enough room to harvest and get turned around in the slop and the mud to go back and make another pass.
"On this farm alone, our loss is hundreds of thousands of dollars. It could be close to three quarters of a million dollars before the dust settles. The analysis right now in the potato and vegetable industry is that the loss is up to $38 million. This is serious -- unprecedented. We have no knowledge of where we're going to end up. This is the worst this farm has ever experienced, and we've been in existence since 1948.
"Young farmers who started this year, will they be around next year? Family farms that have been around since the early 1900s -- will they be able to go through and carry on? The repercussion of this is not just for one season. It's going to last for a while to come. We have a crop insurance program, but it's in 1997 dollars. That's a big hit for agriculture. Those dollars are not going to take a tip off the iceberg for us. They'll barely cover the cost of land rental and partial fertilizer and maybe a little bit of seed. It's just not going to be enough to help farmers get around the corner and have another season."
Being at the mercy of the weather is the fate of farmers throughout history. Actually, not all farmers.
A few miles away, hundreds of acres of greenhouses sitting on agricultural land keep humming away, raising peppers, tomatoes and leafy greens year-round regardless of the weather.
The difference between Bill Zylmans's fate and the greenhouse harvests is the control over weather conditions offered by technology. Ever since the invention of the plow, technology has been helping farmers.
The earliest known use of technology to protect plants dates back to the Roman Emperor Tiberius Caesar (14–37 AD), whose doctor told him he needed a cucumber a day to preserve his health. So he had moveable garden beds built that could be brought inside during bad weather and put outside on winter sunny days under a frame glazed with transparent mica.
The development of cheap artificial light -- especially the LED lighting that's taking over from sodium growlights -- has made the use of indoor lighting for growing a lot more affordable and easier than hauling around mica frames and waiting for sunny days.
"Early adopters" include British Columbia marijuana growers. The renowned "B.C. bud" marijuana, estimated to be worth billions of dollars annually in the underground economy, is grown almost entirely indoors, sometimes in huge underground chambers that never see any natural light.
The widespread adoption of GMO seeds, pesticides, herbicides, fertilizers and antibiotics has revolutionized agriculture. The harm from the collateral damage to natural ecosystems and rural societies from these technological advances is still being tallied, a measure of the mixed blessings that come from technology in agriculture. While genetically modified seeds may end up costing the planet more than the benefits they deliver, that legitimate fear shouldn't let us forget that without technological advances, most of us wouldn't be alive today.
As the writer P. J. O'Rourke once famously pointed out: anyone who doubts the benefits of technological progress should think about one word: "dentistry." He could equally have said "computers" or "refrigeration" or "electricity."
Tech advances on large-scale farms are beyond the scope of this book. Such advances include the sophisticated GPS field maps that allow computer-controlled application of fertilizers that can be customized to subtle changes in soil type across a farmer's fields. But there are many ways technology is going to increase food production for smaller-scale growers in and around cities.
Self-proclaimed "lunatic organic farmer-entrepreneur" Joel Salatin is very clear about the advantages technology can bring to even the most down-to-earth farming practices. "I'm not afraid of using technology," he says. One example is the moveable electric fence system he uses to contain chickens and cattle on different parts of his property. The fences let the animals feed themselves and, at the same time, fertilize the pastures with manure -- so Joel no longer has to buy and transport feed and fertilizer. For him, it's about efficiency: "The weak link is not making better use of the resources we already have."
Greenhouses offer one of the most effective technological boosts for producing more food on less space with fewer resources. One acre of hydroponic greenhouse can produce 600,000 pounds of food per year; that's 10 times what a one-acre field could produce -- and there's no wasted fertilizer.
Hydroponic and aeroponic technology has increased yield potential 20-fold while using 30 times less water than outdoor growing. Those impressive efficiencies have led to booming greenhouse industries around the world -- without the genetically modified seeds, pesticides and herbicides that have played such a big part in the Green Revolution.
The pressure to produce more food in smaller and unconventional spaces has led to vertical farming -- adding height to the traditional one-story greenhouse. Will Allen at Growing Power in Milwaukee is using part of his 2008 $500,000 "genius grant" from the John D. and Catherine T. MacArthur Foundation to build "a five-story vertical building totally off the grid with renewable energy, where people can come and learn, so they can go back to their communities around the world and grow healthy food."
Vertical farms are a natural extension of the evolution of human living spaces into denser, higher, more efficient buildings.
One back-to-the-land prototype for self-contained, homespun vertical farming is the legendary Solviva greenhouse pioneered by the indomitable Anna Edey at Martha's Vineyard in Massachusetts. She designed and built the 3,000-square foot Solviva Solar Greenhouse in 1983, with the goal of producing high yields of high-quality organic food year- round, with no backup heat, no cooling fans and no toxic pesticides. The heating was to be primarily solar, with additional heat provided by living resident heaters: chickens and rabbits. It worked.
To fill orders for what she claims was North America's first fresh, cleaned organic greens packaged mix, Edey stacked four tiers of "grow- tubes" in her solar-and-chicken-heated complex, which allowed her to harvest 90 pounds (1,500 servings) of "Solviva Salad" each week at peak production. Unfortunately, the pressure of keeping her multifaceted operation operating and solvent became too much for her, and she was forced to sell the property. The greenhouse was later demolished. But she did prove her point.
No soil, no sun, no problem
A big advance in vertical growing in a greenhouse or a closed building like a vacant warehouse is coming from Valcent Products Inc., developers of Europe's first vertical farm at the Paignton Zoo in Devon, U.K. It's a hydroponic greenhouse that has 11,000 lettuce, spinach, chicory, chard and herb plants growing in stacked trays that move slowly around a suspended track. On each computer-controlled loop, the plants pass a feeding station that provides water and nutrients and a "shower of lighting" that supplements the natural light. Water and nutrient runoff from the feeding station is captured and recycled. On 1,075 square feet, the zoo is growing $160,000 worth of crops, using only five per cent of the water that would be required to grow them outdoors -- and even that five per cent can be recycled. Valcent CEO Stephen Fane says some animals actually know the difference between vegetables from the greenhouse and commercially grown ones, and they prefer the greenhouse products, if given a choice.
The zoo calculates that it is saving $25,000 a year on its lettuce bill alone. And the advantages of fresh lettuce go beyond the monetary savings: lettuce kept at room temperature for four days loses 82 per cent of its water-soluble protein, 61 per cent of its vitamin C, and 54 per cent of its chlorophylls.
A similar greenhouse has been developed by TerraSphere Systems in Surrey, B.C. It has 11 levels that hold 400 plants each; this allows 20,000 plants to be grown in just 120 square feet of space. That's five times more spinach, for example, than can be grown on a comparable space outdoors
"Without the use of pesticides, herbicides or fungicides, and zero water waste, we can mass-produce food all over the planet," says TerraSphere inventor Nick Brusatore. "We have the ability to mass-produce spinach, strawberries, all the lettuces, all the herbs. We have the ability to grow food in remote locations and urban centers."
A TerraSphere-technology 8,000-square foot lettuce operation opened in Sept. 2010 in Vancouver. It supplies "Eco Spirit" brand lettuce to eight Choices Market stores in Metro Vancouver. Consumers have been, as they say, eating it up. They pay $5.00 for a 5.3-ounce container of the locally grown lettuce. "The quality is excellent, the nutrient levels are high, the shelf life is long," says Choices CEO Mark Vickars. "We're always trying to go local, and this gives us local 365 days a year."
It's hard to believe these high-tech indoor growing systems will not become a vital contributor to food production in the near future. I look forward to seeing them in urban industrial settings, on rooftops, and alongside grocery stores. Because they use little water and don't make a lot of noise or produce unpleasant odors, there's no reason they can't fit into almost any urban space without disturbing the neighbours.
Lighter-weight nutrient film technique (NFT) hydroponics is another technology we should be seeing more of soon. It has an advantage on rooftops because most of the water weight is in a reservoir that can be put on a stronger part of the roof.
One expert has calculated that most of a family's fresh vegetable needs could be met by a 50-square foot indoor hydroponic garden. One 600-watt light could cover the tomatoes and peppers, and two 400-watt lamps could cover the lettuce and herbs.
The big unknown for these new technologies (and one that can spook investors) is the cost of energy for the lights and climate controls. The big greenhouses on the outskirts of Vancouver struggled when natural gas prices rose, then had difficulty with air quality regulations when they tried to switch to wood pellets or hog fuel (leftover bark chips and wood fiber from mills). One Vancouver greenhouse grower, CanAgro Greenhouses, teamed up with Maxim Power Corp. to demonstrate an eco-industrial approach by capturing methane that would otherwise be released to the atmosphere by an adjacent landfill. The methane is piped under a highway to a co-generating plant that makes power for the grid and uses heat from the manifold for the adjoining 63-acre greenhouse.
Some urban growers have found a similar solution by heating rooftop- grown plants using waste heat from the building below. Eli Zabar, for example, heats his Manhattan rooftop greenhouse with exhaust heat from the bakery below.
Investors discovering hydroponics
Companies that manufacture indoor growing technology are scrambling to get the technology, energy savings, financing and management aligned to meet the huge demand that’s coming as outdoor-grown food prices keep rising and people are demanding local fresh food. An executive with Valcent said he is following up on 150 requests for orders from 20 countries.
Investors from the green tech world are just waking up to the financial opportunities. "Sustainable agriculture is a space [for investment] that looks as big or bigger than clean tech," says Paul Matteucci, a venture capitalist with U.S. Venture Partners in Menlo Park, Calif. "Historically, we have not seen a ton of entrepreneurial activity in agriculture, but we are beginning to see it now, and the opportunities are huge." Investors are waking up to conventional agriculture's contribution to climate change, and they are increasingly aware of its dependence on huge amounts of water and fossil fuels that are becoming more expensive and less available.
Investors already into clean tech and life sciences are realizing they can make money out of the coming transformation of industrial agriculture. One Silicon Valley green tech firm is backing a company that's making tools to measure the nutrient content of soils in real time, allowing more precise applications of fertilizer, which saves money and avoids nitrogen runoff and pollution of waterways. A New York firm, NewSeed Advisors, has started "Agriculture 2.0" conferences to showcase new ag tech opportunities.
Once a critical mass of financiers, lawyers and investors understand the entrepreneurial sweet spots in meeting new demand for indoor urban food production, a lot of new companies offering tech solutions will be jumping in.
One dream project that continues to be held out as a beacon of what's possible is Columbia University public health professor Dickson Despommier's 30-story futuristic vertical farm. The size of a city block, it would cost hundreds of millions of dollars -- but it could feed 50,000 people. Build 160 of them, and you could feed all of New York, he says. He came up with the idea after his students went looking for rooftop garden spaces in Manhattan that would be suitable for growing food. They identified only 13 acres (and concluded that rice would be the best crop to grow). That amount of space could satisfy only about two per cent of Manhattan's food needs. So, his students then turned to NASA, and they learned that numerous small-scale projects have demonstrated that anything can be grown indoors. But nobody was seriously considering growing food in tall buildings. The main reason -- aside from uncertainty about whether it would work -- is the cost of construction and energy. "Scores of companies have tried to do this, even the big guys like General Mills 15 years ago," says Bruce Bugbee, a professor of crop physiology at Utah State University. "It's too expensive. People don’t realize how much light it takes to grow plants."
Despommier set out to design a completely closed-loop system:
"All the water is recycled, all the nutrients are recycled. The only thing that actually leaves the building is the produce.
"The big question is who's going to be doing this? Who wants to do it? Who needs to do it? And who can do it? The answer is: countries that don't have agriculture -- Iceland, all the Emirates.
"You've got a lot of people and you've got almost no land. Here's a wonderful way of conserving water and providing food for everybody.
"What about those places that want them? China and India have been wanting these for years. The technology has finally caught up to the desire, and now, I think they're going to start building them.
"What if you had a vertical farm that specialized in one crop, like we have outdoors -- corn, rice, wheat. Imagine the ancillary industries that would spring up around these farms in an urban setting, to employ even more people. From wheat you can make flour, from flour you can make bread or cupcakes, and it comes from that building. The biggest social benefit is that everybody gets fed healthy, clean food, and you can remediate it to clean water. So you can have safe water and safe food wherever you live.
"I've had no negative reaction to this idea. I think the idea is about to develop into reality."
Energy costs undermine growing indoors
Before getting too excited about indoor growing, keep in mind that these are costly man-made systems that re-create what's available free in nature. A greenhouse has to use man-made energy to regulate temperature, irrigation, fertilization, light, CO2 content, and air circulation. Eliminating nature's unpredictability and rough edges comes at a cost. Current state-of-the-art closed greenhouses can cost more than $1 million/acre. However, these greenhouses have yields 40 per cent higher than open or vented greenhouses because of better pest management, lower energy costs, and better use of captive CO2.
A Netherlands study found that vegetables grown in greenhouses require 57 times as much non-renewable energy than the same vegetables grown in an open field. That number is disputed by those who say energy productivity has to take into account food miles for distribution (what if the greenhouse is on the roof of a grocery store?) and food waste in the field (nothing is wasted in greenhouses).
"The only viable food we can ever produce is that which is a by-product of our relationship with the soil," Vandana Shiva reminds us in Dirt! The Movie. Taking into account fertilizers needed to feed soil and distances to market, the viability of soil-grown food in an oil-challenged world is changing. Finding soil for growing is one of the biggest challenges for the future of food. With the human population expected to top 9 billion within 50 years, feeding all the new people will require an additional 270 million acres of farmland that doesn't exist today. Carving it out of dwindling forests comes at a huge cost to the planet's biodiversity -- assuming that the required amount of forested land is even available.
A big threat from indoor agriculture is that it provides an excuse to stop preserving agricultural lands and soils. If we can grow all we need indoors, what's the problem with paving over farmland even faster than we are now? But billions of the world's farmers depend on the free ecological services provided by nature. The vast majority of these farmers will never be able to afford to build greenhouses. They will be challenged enough by the trend to price "free" natural assets (such as potable water) in an effort to protect them and ration their use.
We will always need farmland. Indoor growing has to be seen as a supplement to outdoor growing, not a replacement for it. Fields will always be more suitable for growing crops like grains, rice and corn. Hydroponics and urban and near-urban plots will increasingly supply other crops.