From shipping containers-turned-microfarms to fruit-picking robots, the wide world of agriculture tech is attracting attention and investor dollars as increasingly urgent concerns about food scarcity come into focus.

Amid a wave of in-field technology, food data analytics and experimental urban agriculture, the particularly futuristic field of vertical farming is attracting entrants including industrial incumbents such as Fujitsu and upstarts such as AeroFarms, City Farm and Green Sense.

As ag tech blooms, attracting a total $4.6 billion in investment during 2015, the nonprofit Association for Vertical Farming is positioning itself as a leader of the segment of the market.

With an international roster of members that includes multinational companies such as Microsoft, Philips and Metro Group, plus smaller enterprises such as AeroFarms and Agrilyst, the industry group aims to grow the industry through events, advocacy and policy work.

“We do a lot to try and think five, seven years ahead for the industry,” Andrew Blume, the association’s North American regional manager, told GreenBiz.

Among the frontiers Blume and Association for Vertical Farming co-founder Henry Gordon-Smith see on the horizon for the field is sustainability. Specifically, the group is in the early stages of studying and formulating the first sustainability standard for vertical farms.

The compact geographic footprints and diminished water and soil inputs for vertical farms may seem like obvious advantages, but critics say that high energy requirements for lighting complicate the environmental calculus. What happens to food quality when you reduce or subtract organic soil is another question.

“There are big losses of energy and heavy infrastructure costs. It’s about as wasteful as a system can be,” journalist Stan Cox recently wrote for AlterNet. “Better to let crop plants do what they do best: capture cost-free, emissions-free sunlight for themselves.”

In an interview edited for length and clarity, Blume and Gordon-Smith weighed in on the sustainability question, along with the prospect of vertical farms becoming an everyday part of city life.

Lauren Hepler: So what is the Association for Vertical Farming?

Andrew Blume: The Association for Vertical Farming is an international nonprofit that’s about three years old. It was just founded basically out of a need for an association and a way for people to talk about the industry and to bring about standardization in kind of the way that we practice vertical farming, and in the way we communicate our work and the different characteristics of the vertical farms themselves.

We don’t just do vertical farms for the sake of vertical farms. We do a lot to try and think five, seven years ahead for the industry. So, we do things like a sustainability certificate that we’re currently working on.

Hepler: What are some of the issues that are top of mind for the industry right now? It sounds like sustainability is up there, given that you’re thinking about ways to set standards.

Henry Gordon-Smith: At the beginning, it was really awareness and education. Now it’s more about how we help cities and policy leaders interpret what vertical farms are. What makes one better than the other? What makes one worth supporting versus the other? Are they really job creators? Can they be organic? Are they sustainable?

These are questions that policy leaders want to know about. Also, [what] kind of physical elements, like where they should be integrated. How can they think about health and safety or planning around these vertical farms?

The other part of the sustainability question, which is relatively new: About eight months ago, probably, we initiated a study with Columbia University to look at what makes a vertical farm sustainable or not, and even extend that to greenhouses and other urban farms.

Vertical farms are an intersection among farming, technology and building, requiring unique certification.

Students went around and looked at LEED, they looked at fair trade, they looked at organic. They rated them based on how applicable they would be to the main components in vertical farming. Right? Water use, electrical, lighting, space usage, integration to buildings, social impact.

They looked at all these different certifications and concluded that we should develop our own. Why? Because vertical farms are kind of this intersection between farming, technology and building, so they require sort of their own unique certification.

Hepler: How do you move from studying sustainability to setting concrete standards?

Gordon-Smith: The Columbia students presented a plan for how we could get to a viable certification scheme within, let’s say, five to seven years, which is how long it typically takes to get a certification off the ground.

We are now initiating benchmarking with 10 starter farms. It’s not really, let’s say, responsible of us to say, “This is how we define a sustainable vertical farm” and then say, “You can either be certified or not.” (It’s more) saying, “Your first 10 farms, we’re going to spend a year with you tracking things that are, let’s say, a bit basic, like water usage, your number of laborers, your grow area versus your building footprint, your distance to market.” OK? And there’s 10 initial metrics that we’re doing and that’s some of them.

The next year, we would expand that group to 20 and add an additional—I think it’s five—metrics. So, now we’re stretching them to ask them deeper sustainability questions. Once that year is done, we can then create a third-party group or partner with a third party group that can be the verifier—the certifier, let’s say, and then we become the verifier.

Hepler: There are so many inputs with agriculture: water, energy, soil nutrients. Where are we now with vertical farming, and what is the opportunity for efficiency and sustainability moving forward?

Gordon-Smith: Where we are now is people are investing more, and people continue to take the risk—and it is a risky business, vertical farming, but an exciting one. We feel that it’s our responsibility as an organization to ask the proper questions.

It’s not good enough to say we’re producing jobs or we’re saving an approximate amount of water. Cities are going to start asking deeper questions, especially when they start to encourage or discourage this kind of farming. And we think that’s a risk to our members.

I think in general, the sustainability of vertical farms is still quite questionable. A lot of people need to be tracking more things to add to that question. And what are we really comparing it to? We’re trying it to compare it to conventional agriculture, and even those impacts haven’t been quantified appropriately. We’re optimistic about the sustainability of vertical farming, especially from the water perspective and the food model perspective.

Blume: I would just add that LED lights are getting much more efficient. The renewable energy sources are going to also continue to get more efficient, whether it’s solar or wind or these renewable sources. And for me, a big part of it is just about making cities more resilient and preparing for climate change.

Other industries will continue to progress and get better. Their technologies will converge with ours to make vertical farming more sustainable. So, vertical farming isn’t just kind of in this bubble where we’re just going alone needing to make everything more sustainable.

After Hurricane Sandy, soil-based urban and local farms around New York City were damaged, but indoor farms weren’t.

Gordon-Smith: It’s a great point. If you look at New York City after Hurricane Sandy, soil-based urban farms and even some local farms around the city were damaged, but indoor farms weren’t. I mean, there is the possibility of losing power, but that can also be navigated with some generators, which a lot of commercial farms have.

So, there’s a resiliency argument there when the city of New York only has two days’ food supply and storms are going to be more prevalent. Who’s going to provide that backup produce? It’s probably going to be vertical farms.

Hepler: The District of Columbia’s put out a new climate adaptation plan that includes food security and urban farming as prerogatives. Are there particular cities that you think are out in front on this idea? And also, what’s the business model here?

Blume: I would say that New York City is fairly advanced. There are a lot of different rooftop gardens there. The New York Ag Collective is really pushing forward. They have New York Ag Tech Week coming up in September where there’s going to be a lot of technology demos and policymakers all coming together.

Chicago is fairly advanced with—they’ve got a handful of urban and vertical farms there. Los Angeles is behind, but we’re catching up. Internationally, I would say Japan is extremely advanced with vertical farming.

Gordon-Smith: I think Singapore is also on the list for sure. It’s an island country that spends a lot on imports.

Hepler: How much food are we talking about? Have you found a sweet spot in terms of scale?

Gordon-Smith: Right now, the scales that are the most, let’s say, economically viable are, I’d say, around 10,000 (square feet) or more when you’re really getting the large ones. The equipment you’re buying—you’re going to get a better deal on it. And at that size, it always depends on the operator, but you can plan your labor very intelligently. Then the volume at that production, you can actually get some very interesting supermarket deals. There’s a lot of variability here, by the way, because when we think 10,000 square feet, that’s the building area. There could be multiple levels.

When you go smaller, to the kind of 1,000 square feet or 2,000 square feet, you can fit into interesting spaces, like unused spaces in the city. You’re not going to be making tons and tons of money but you’re going to be making profit. Also, you’re going to be selling more of a specialty product. You’re probably going to be closer to the market if you plan it out properly.

Hepler: What about distribution? Is food grown in vertical farms marketable, or are there other factors to consider when it comes to selling this stuff?

Blume: One of our members, the German conglomerate Metro Group, they have a chain of retail stores in Germany. They’re a bit more cutting-edge, and they have a position on their staff for head of food tech and food innovation. They partnered with another one of our members in Germany and set up an in-grocery-store farm right there where they’re now growing some microgreens like bonsai basil and chard.

As to seeing it here in the U.S., I do also know of some restaurant chains and others that are purchasing from a company here in Los Angeles.

Gordon-Smith: It depends on the crop, right? It’s a very, very tough world out there for distribution. People are impatient. People are always trying to cut costs where possible. It’s a relationship business and you have to pick the right crop.

But usually, they’re very excited about the fact that it’s year-round. If you can give the buyer basil in the wintertime or any leafy green that’s fresh in the wintertime, they get excited about that. I mean, it’s a pesticide-free local product, which can be very interesting.

Hepler: We hear a lot about leafy greens, but how do you see the types of crops being grown this way evolving?

Gordon-Smith: It’s an exciting question. Right now, the diversity is, let’s say, relatively limited. It’s leafy greens, microgreens. But it’s getting more interesting over time. I think the new crops that are going to be coming onboard from an economics perspective are probably going to be strawberries and other berries.

I think that’s going to be increasingly viable. And it makes sense, right? It kind of fits in a similar space requirement. It requires a different lighting spectrum and a different growth cycle, but it’s in the future for vertical farming for sure.

Tomatoes, cucumbers, peppers—I think we still have a long way for those to become economically viable. You will see some companies depending on vertical farms just to grow healthy young plants that are then put into fields or put into greenhouses that are maybe near the city. That’s already happening in some ways.

I think what we’re not going to see for a long time, if ever, are people growing wheat and corn and those kind of, let’s say, staple crops. It also makes sense, because those don’t need to be fresh. It’s not required; they store well. So, wherever a product doesn’t store well, and they have high margins, and they’re in demand, and they’re imported, that’s where vertical farming is going to start to really shine in the coming five years.

Hepler: What about designated labels for food grown on vertical farms?

Gordon-Smith: There’s no label right now that’s out there. One of the things we’re thinking about for the certification is that you could have a label about the farm itself, verifying its social mission or its food miles or something like that.

Most vertical farms will pursue their own or an existing label. So, they’ll pursue—if they’re very, very ambitious—they’ll pursue organic, which is challenging but possible. A few in New York will pursue New York-made. A lot of them will pursue GMO free. There’s a vertical farm in Philadelphia that’s vegan-certified.

Hepler: Why is organic such a challenge for vertical farms?

Gordon-Smith: These systems are highly capital-intensive. So, to have a delay once you launch is very difficult, and you can’t really be certified until you’ve launched. You need to be paying for labor, operating lights.

Another one is the plumbing. Hydroponic plumbing systems are sensitive. There’s basically dissolved nutrients that are delivering the nutrients to the plant, and when organics are dissolved they have a different size than non-organic nutrients and they don’t dissolve as well.

Hepler: From a competitive standpoint, do you see more big companies wading into this space looking to acquire people? Should we expect more new entrants?

Gordon-Smith: I think those bigger corporations are already investigating the space and looking into how these technologies are going to influence their activities. I don’t know if it’s going to be so much acquisition as much as it will be just new ventures.

I think there’s still a lot of opinions out there about the state of the industry and the opportunity of just getting involved and catching up. It is still relatively new, so if you have enough capital and if you can recruit the right talent, I think it’s still quite wide open.

Hepler: What are the primary roadblocks you foresee for the industry?

Gordon-Smith: The first one is for people to actually understand what it is. The policy leaders, especially on the city level, don’t understand how it’s going to integrate into their department of building codes or what can they grow in these farms. A lot of them don’t understand the actual jobs impact of it when trying to develop incentives, because there’s kind of this paradox between creating jobs for getting economic benefits for the city and then reducing jobs for actually having a lean operation that’s more automated. And that’s a bit of the paradox in commercial vertical farms.

And then, the other part is just how does it fit into the spectrum of urban agriculture as a whole? Because those other typologies have value from a green infrastructure perspective—managing rainwater or a community impact perspective from being more exposed to the public. Vertical farms are typically a bit more enclosed and factory-like. It’s confusing for some people because there’s this aura and existing zeitgeist around urban agriculture.

This piece first appeared in the Insights section on GreenBiz.com.