Standing aquaponics on its head

Posted: May 20, 2013

How can a small urban space produce a lot of fresh vegetables? By standing conventional wisdom on its head and a shipping container on its end.
The GreenTowers team at work on its prototype.

The GreenTowers team at work on its prototype.

Those long, narrow boxes pulled by semi-trucks — officially known as intermodal steel building units — can be used to house a vertical aquaponics system and produce crops like lettuces, basil, chives, cilantro, tomatoes and cucumbers.
That’s the concept driving GreenTowers, a business start-up team of Penn State students led by Dustin Betz, a senior plant biology major who is also working on a minor in horticulture and a minor in engineering and entrepreneurship. 
This summer, the GreenTowers team is busy testing the concept by first building a horizontal prototype at the Russell E. Larson Agricultural Research farm at Rock Springs. 
Unlike actually standing the container on its short end, the initial orientation won’t require an elaborate overhead lifting mechanism to install the container on site.
“We believe this design will allow us to more easily comply with eventual zoning laws and ordinances. Vertical integration is still at the heart of our innovative drive, as stacked grow beds are also included in the horizontal design,” says Betz.
If successful at creating an affordable system and service, GreenTowers can tap into the demand for agriculture production in urban areas, which can be difficult to reach with fresh, affordable produce. 
“We believe [urban agriculture] can transform communities,” says Betz. “That’s the social need and the business model we’re working on.”
Betz and his teammates won first place and $5,000 in the Ag Springboard business plan competition in November, 2012. 
Betz had initially pitched the concept of an aquaponic, vertically integrated greenhouse at the AG60 elevator pitch competition in spring, 2012, and quickly found partners to work toward the Ag Springboard competition. 
Both events are part of the Entrepreneurship and Innovation program at Penn State’s College of Agricultural Sciences. 
“The Ag Springboard provided all of the structure for us,” says Betz. “The common goal when we came together was: Let’s win the competition and build this thing.” 
Adds Betz: “We were in it to win it. That’s the mentality we had the whole time. We did the competition, now we’re starting to build it in a modified sense."
The current GreenTowers team consists of Betz and Mike Ghen, a computer engineering major, part of the team from the start. 
Ghen works on software to automate greenhouse management and customized LED lighting. 
Jon Gumble, a graduate horticulture student, works on the theoretical logistics of transport and on-site installation. 
Jared Yarnall-Schane, a senior mechanical engineering major, works on the mechanics and is increasingly focused on marketing research and design mechanics, says Betz. Yarnall-Schane is working toward a minor in Engineering Entrepreneurship and Leadership.
Mike Zaengle, an architecture major who just completed his third year, works on 3D modeling and rendering, and has also been integral in all elements of planning the greenhouse design, and producing 3D models and renderings, says Betz. 
“He’s helped a whole lot in being able to effectively communicate the concept,” says Betz.
Ken Palamara, an energy engineering major who just completed his junior year, worked on the team for the Ag Springboard competition, but is not actively working on the project. 
The team is taking the technology it has used in smaller prototypes and using it on a larger scale in the shipping container.The growing technology is deep-water culture, in which plant roots are suspended in aerated water, as well as flood-drain aquaponics, in which plants grow in clay pellets that are periodically flooded.  Each grow bed is about a foot deep.
”The team is busy testing various crops in each of those hydroponic grow beds, and arranging and re-arranging them within the shipping container. 
“One of the things we really want to do with the entire ISB-unit business model is to be able to space the growbeds to meet customer needs,” says Betz.“If I’m the restaurant owner, all I have to do to have fresh greens growing on-site is go out and cut them myself,” says Betz. “That’s the service we’re trying to build.”
To that end, Green Towers has used about $2,500 of its Ag Springboard award money for the structural safety analysis and to sponsor an engineering capstone design team to design a workable, adaptable modular growbed system that can be easily re-arranged to suit the crops the customer wants to grow, says Betz.
The rest of the winnings are going toward building the prototype, at a total estimated cost of $5,000.
Upscale restaurants interested in growing their own produce on-site would be one of the core markets for the setup and service, says Betz. 
Others include emergency disaster and humanitarian relief. The future company could ship in a prefabricated grow system and quickly provide fresh produce, says Betz. It could also provide community gardens in unconventional places, like urban neighborhoods. 
The team also participated in the Dell Social Innovation Challenge, a Dell-sponsored competition for student innovators who want to apply their transformative ideas to solving the world’s most pressing problems, and is enrolled in the Thought for Food Challenge
“We would really like to build a social business model,” says Betz, “so that for every 20 or so containers we sold to restaurants, one could then be donated to a low-income area or food desert. 
Once the prototype is complete, the next step will be an intensive horticultural R&D stage. 
“We will aim to quantify the vegetative outputs possible across a wide variety of crops that we believe will appeal most to our anticipated breakout-market, restaurants,” says Betz. “With that data in hand, and the prototype operational, we will have much more legitimacy in approaching these potential first customers and/or early investors.”