Editor’s Note: In our latest Making Sense segment, economics correspondent Paul Solman explores the business of urban farming. Paul spoke with Viraj Puri, the CEO of the urban agriculture start-up Gotham Greens. On a rooftop above a Whole Foods in Brooklyn, Puri spoke about urban agriculture’s efficient use of space, buying local produce, and whether urban agriculture could solve the growing global food crisis.
The following conversation has been edited and condensed for clarity and length. For more on the topic, tune into tonight’s Making Sense, which runs every Thursday on the PBS NewsHour.
— Kristen Doerer, Making Sen$e Editor
Viraj Puri: The produce that is grown here is partially sold to the Whole Foods downstairs, to other Whole Foods across the New York City area and to restaurants.
In our controlled growing environment, we’re able to grow a head of lettuce in about 30 days from seed to harvest – about half the amount of time it would take in conventional, soil-based farming.
This greenhouse that we’re standing in is about 20,000 square feet so about half an acre, yet the yield we achieve is about those of a 20-acre farm. It’s about 20 times more efficient per unit area.
Paul Solman: Could you do this through vertical farming? In other words, level by level?
Viraj Puri: It could be done level by level. The big challenge is lighting. Plants need light to grow – it’s what aids photosynthesis. By stacking plants on top of plants, you need levels of artificial lighting between them, which is extremely energy intensive, and currently, it has not been proven to be economical. However, a lot of advancements are being made in terms of energy efficient lighting, such as LED lighting, but it’s not quite being done on a commercial level yet.
Paul Solman: But these lights above us are quite energy intensive, aren’t they?
Viraj Puri: Yes, they do use more energy than conventional lights. They’re particularly well suited to growing crops. We use this as supplemental lighting, and there is a very big difference between supplemental lighting and artificial lighting. We use these lights a couple of hours a day for about six months of the year as opposed to completely indoor stacked farming that requires lights 365 days a year, 24 hours a day.
Paul Solman: I hope you’ll forgive me for saying this, but why Brooklyn, New York? Why did you pick Brooklyn, NY as the place for the sun to shine?
Viraj Puri: Brooklyn is a special place, and we’re seeing so much innovation. It’s on the cutting edge of science, media, art, fashion and food. We have this growing urban population that increasingly cares about where they get their food, how it’s grown, who the people are growing it, whether it is close enough to them and what it really represents.
This food is not superior just because it is grown closer to them, but because of the effort that our growers put into making sure it very nutritious and tasty. Being fresher, it’s going to be more nutritious. So our proximity to our customers enables us to get our product to them within 24 hours of harvest. More conventionally grown salad greens come from as far away as California, Arizona or Mexico. Often the leafy greens that we buy at a supermarket or eat at a restaurant is a week old before we get it, which really compromises the flavor and the nutrition, and it has a carbon impact from shipping that product over long distances.
Paul Solman: And it’s closer to the consumer. In my reporting I’ve found that people want to be localvores, so they really want farm-to-table or in this case, farm-to-supermarket.
Viraj Puri: Locavorism is a growing trend, and I believe it’s not just because people want food that’s grown closer to them — that’s a big part of it — but it’s what that represents. It represents spending dollars closer to home, it represents artisanal, small batch, craft manufacturing, not large, anonymous agribusiness.
Paul Solman: If they wanted to, people could simply go upstairs from the Whole Foods and see where the food comes from.
Viraj Puri: Especially in this location, people can literally come and see where the food is grown and then buy it on the supermarket shelves downstairs. This particular facility in partnership with Whole Foods and Gotham Greens is very symbolic of the locavore movement.
Paul Solman: Is this organic, and if it isn’t, what is organic anyway?
Viraj Puri: Here at Gotham Greens we employ hydroponic techniques, so it’s not technically certified organic according to USDA standards. When the USDA developed standards for organic agriculture, it was intended to be primarily a soil-protection rating system. In hydroponics we don’t really use any soil, and we’re eliminating any sort of run-off from agriculture to the groundwater and into the soil, so it’s sort of a moot point. The current USDA standards are not really applicable to hydroponics, but that being said, at Gotham Greens, all of our produces is pesticide free, which is extremely important to us.
Paul Solman: And how do you get the power for these lights?
Viraj Puri: We’ve designed all of our greenhouses to be as energy efficient as possible — we have sensors all over the green house that are tracking temperature, CO2, light level, oxygen, etc. All of that information is transmitted to a computer control system that we’ve programmed to turn the equipment on and off to achieve the desired conditions in the greenhouse. In addition to that, we’ve selected high-efficiency equipment to conserve overall energy use. We have shade curtains here that act as thermal blankets in the cooler months that reduce the amount of air that we need to heat. We use advanced glazing materials that help insulating. We also capture waste heat from the building below that reduces our overall heating demand.
Paul Solman: Do you think there is a world food crisis either happening now or in the making?
Viraj Puri: There are several significant issues with our current food system. There’s a tremendous amount of waste, and there is a tremendous amount of resources that go into agriculture. Agriculture is the largest consumer of land on the planet, it’s the largest consumer of fresh water, it’s the leading source of water pollution, and it’s also responsible for about 15 percent of global carbon emissions. While our global food system does feed billions of mouths each day, there are a number of significant challenges, and what we’re beginning to see all around the world are more efforts toward more sustainable forms of agriculture.
Paul Solman: If there’s a world food crisis — either happening or in the making — how much of the problem can be solved by solutions like yours?
Viraj Puri: The global food crisis is complex with a lot of varying factors, and there are differing factors affecting different parts of the world.
I don’t believe that urban agriculture in the developed world will ever produce the majority of the urban population’s nutritional needs, however urban agriculture has a very important role to play. It has community development attributes, and it has pedagogical attributes to our students, teaching them how food is grown and where it comes from. It boosts economic development opportunities and creates urban green space. It can symbolize adaptive reuse of urban space. So urban agriculture has a lot of benefits – feeding populations is one of them – but I don’t believe it’s the primary one.
Paul Solman: What about in the so-called developing world?
Viraj Puri: I believe in the developing world urban agriculture has more of a subsistence nature — people need to farm that food to eat. They don’t have the benefits of going to markets and restaurants to buy their food, they need to grow it themselves, and that’s increasingly happening in inner cities in the United States.