Urban farming is being taken to new heights in an abandoned Chicago pork processing plant where environmentalists hope to “get off the grid” by using the waste from one crop to feed and power another.
Schools of tilapia swim in water cleaned by the roots of leafy greens that feed on the nitrogen and other nutrients in the fish waste.
A bakery will later move in that will be able to use mash from the brewery upstairs to fire its oven, and a generator that can convert compost into biogas to power everything from the grow lights to the air conditioning is expected to be up and running sometime next year.
“What we’re trying to do is teach people that there’s a better way,” said John Edel, who bought the factory dubbed “The Plant” two years ago and is spearheading its development.
“The path we’re on right now is unsustainable,” he said. “We have to do something and we have to do it quickly or we’re all stuck.”
Vertical farming was once relegated to science fiction — the stuff of lunar colonies or dystopian metropolises.
It was too costly to try to build — and heat — multi-story greenhouses and it did not make sense when farmland was so cheap, abundant and fertile.
A growing interest in locally produced, sustainable food — coupled with increased concern about the impact of climate change and population growth on available, good farmland — has spurred scores of experiments with vertical farming.
So far, it hasn’t proven to be commercially viable, but that doesn’t mean it won’t be.
“What you’re looking at right now are the early stages of a Thomas Edison light bulb,” said Dickson Despommier, a professor of public health at Columbia University and author of The Vertical Farm.
The potential benefits are huge.
Indoor farming eliminates the need for harmful pesticides and herbicides and protects crops from drought, early freezes and storm damage.
It can also drastically increase yield per hectare by stacking farm on top of farm and allowing for year-round production. With fast-growing but sensitive strawberries, for instance, an acre (0.4 hectare) of greenhouse can produce up to 30 times more than a farmer’s field, Despommier said.
Growing food in the cities where it is eaten cuts down on fuel used to truck it in from farms that can be thousands of kilometers away and also means people get to eat fresher and tastier produce.
The problem is the cost.
Sunshine is free, while grow lights and greenhouses are expensive. Farmland costs a lot less than urban skyscrapers, and large-scale harvesters can collect crops from a field a lot faster than people can pick them.
The technology exists to drastically reduce the cost of vertical farming, Despommier said. It is just a matter of figuring out how to efficiently integrate and automate indoor farming systems.
“We need a lot more work, and the work that needs to be done needs to be done in a way that can be shared with everybody else,” he said in a telephone interview.
That is exactly what Edel is trying to do at The Plant, where the goal is to reduce waste, increase efficiency and achieve “net zero” energy use by closing loops.
Finding the right building was critical to keeping costs down.
Edel bought the abandoned pork processing plant in 2010 for just US$525,000 — pretty much the value of the scrap inside.
The four-story, 8,690m2 building had solid brick walls to keep the pork cool, a recently upgraded electrical system, and it was filled with food-grade stainless steel, rubberized concrete floors and other materials that Edel and his tenants are repurposing for their own use.