What if "eating local" in Shanghai or New York meant getting your fresh produce from five blocks away? And what if skyscrapers grew off the grid, as verdant, self-sustaining towers where city slickers cultivated their own food?
Dr. Dickson Despommier, a professor of public health at Columbia University, hopes to make these zucchini-in-the-sky visions a reality. Despommier's pet project is the "vertical farm," a concept he created in 1999 with graduate students in his class on medical ecology, the study of how the environment and human health interact.
The idea, which has captured the imagination of several architects in the United States and Europe in the past several years, just caught the eye of another big city dreamer: Scott Stringer, the Manhattan borough president in New York.
When Stringer heard about the concept in June, he said he immediately pictured a "food farm" addition to the New York City skyline. "Obviously we don't have vast amounts of vacant land," he said in a phone interview. "But the sky is the limit in Manhattan." Stringer's office is "sketching out what it would take to pilot a vertical farm," and plans to pitch a feasibility study to the mayor's office within the next couple of months, he said.
"I think we can really do this," he added. "We could get the funding."
Despommier estimates that it would cost $20 million to $30 million to make a prototype of a vertical farm, but hundreds of millions to build one of the 30-story towers that he suggests could feed 50,000 people. "I'm viewed as kind of an outlier because it's kind of a crazy idea," Despommier, 68, said with a chuckle. "You'd think these are mythological creatures."
Despommier, whose name in French means "of the apple trees," has been spreading the seeds of his radical idea in lectures and through his Web site. He says his ideas are supported by hydroponic vegetable research done by NASA and are made more feasible by the potential to use sun, wind and wastewater as energy sources. Several observers have said Despommier's sky-high dreams need to be brought down to earth.
"Why does it have to be 30 stories?" said Jerry Kaufman, professor emeritus of urban and regional planning at the University of Wisconsin, Madison. "Why can't it be six stories? There's some exciting potential in the concept, but I think he overstates what can be done."
Armando Carbonell, chairman of the department of planning and urban form at the Lincoln Institute of Land Policy in Cambridge, Massachusetts, called the idea "very provocative." But it requires a rigorous economic analysis, he added. "Would a tomato in lower Manhattan be able to outbid an investment banker for space in a high-rise? My bet is that the investment banker will pay more."
Carbonell questions if a vertical farm could deliver the energy savings its supporters promise. "There's embodied energy in the concrete and steel and in construction," he said, adding that the price of land in the city would still outweigh any savings from not having to transport food from afar. "I believe that this general relationship is going to hold, even as transportation costs go up and carbon costs get incorporated into the economic system."
Some criticism is quite helpful. Stephen Colbert jokingly asserted that vertical farming was elitist when Despommier appeared in June on "The Colbert Report," a visit that led to a jump in hits to the project's Web site from an average of 400 daily to 400,000 the day after the show. Despommier agrees that more research is needed, and calls the energy calculations his students made for the farms, which would rely solely on alternative energy, "a little bit too optimistic." He added, "I'm a biologist swimming in very deep water right now."
"If I were to set myself as a certifier of vertical farms, I would begin with security," he said. "How do you keep insects and bacteria from invading your crops?" He says growing food in climate-controlled skyscrapers would also protect against hail and other weather-related hazards, ensuring a higher quality food supply for a city, without pesticides or chemical fertilizers.
Architects' renderings of vertical farms — hybrids of the Hanging Gardens of Babylon and Biosphere 2 with SimCity appeal — seem to be stirring interest. "It also has to be stunning in terms of the architecture, because it needs to work in terms of social marketing," Despommier said. "You want people to say, 'I want that in my backyard.' "
Augustin Rosenstiehl, a French architect who worked with Despommier to design a template "living tower," said he thought that any vertical farm proposal needed to be adapted to a specific place. Rosenstiehl, principal architect for Atelier SOA in Paris, said: "We cannot do a project without knowing where and why and what we are going to cultivate. For example, in Paris, if you grow some wheat, it's stupid because we have big fields all around the city and lots of wheat and it's good wheat. There's no reason to build towers that are very expensive."
Despite its potential problems, the idea of bringing food closer to the city is gaining traction among pragmatists and dreamers alike. A smaller-scale design of a vertical farm for downtown Seattle won a regional green building contest in 2007 and has piqued the interest of officials in Portland, Oregon. The building, a Center for Urban Agriculture designed by architects at Mithun, would supply about a third of the food needed for the 400 people who would live there.
In June at P.S.1 Contemporary Arts Center in New York, a husband-wife architect team built a solar-powered outdoor farm out of stacked rows of cardboard tube planters — one that would not meet Despommier's security requirements — with chicken coops for egg collection and an array of fruits and vegetables.
For Despommier, the high-rise version is on the horizon. "It's very idealistic and ivory tower and all of that," he said. "But there's a real desire to make this happen."