Green Towers: Production and Financial Analyses of Urban Agricultural Systems
Open Access
- Author:
- Gumble, Jonathan James
- Graduate Program:
- Horticulture
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- June 22, 2015
- Committee Members:
- Robert Berghage Jr., Thesis Advisor/Co-Advisor
Dan Thomas Stearns, Thesis Advisor/Co-Advisor
Mark A Gagnon, Thesis Advisor/Co-Advisor
Andrew Scott Lau, Thesis Advisor/Co-Advisor - Keywords:
- "GreenTowers"
"food deserts"
"urban agricultural design"
"Rotating Living Wall"
"Living Furniture" - Abstract:
- By the year 2050, the population of planet Earth is expected to reach over nine billion people. In the next 35 years, we will have the task of supporting an additional two billion lives on a planet that is already struggling to provide a stable and acceptable food supply as well as an effective means of food distribution. Estimates show that of the seven billion people living on planet Earth, 870 million suffer from hunger. The fight against world hunger is a complex, challenging, and multi-faceted issue that can only be fought through innovative solutions that address the multiple aspects comprising it. One of these aspects is simply limited access to food in urban neighborhoods and rural towns which are referred to as “food deserts”. These are prevalent throughout the United States and have resulted in food-insecure households. Solutions to limited access do exist today in the form of innovative growing on developed land. The use of controlled agricultural environments through the means of greenhouse structures, LED lights, hydroponics, aquaponics, and aeroponics have made this possible. Multiple companies have come into existence and have built their businesses out of providing these innovative growing systems or growing food through their utilization. Although these techniques and systems do exist, there is limited information and data on production yields both from the companies themselves as well as from existing scientific literature. GreenTowers, LLC is an Urban Agricultural Design Company that came into existence in the past three years as a result of Penn State University’s College of Agricultural Science’s 2012 Ag Springboard Competition. The four co-founders; Dustin Betz, Jared Yarnall-Schane, Michael Zaengle, and Jonathan Gumble have transformed GreenTowers from a student competition team, to a full-time business. GreenTowers’ mission is “to reconnect individuals with nature and with food to help consumers realize the interconnection shared between ecological systems and food systems”. This is primarily accomplished through the use of two innovative growing systems developed by the company; the Rotating Living Wall and Living Furniture. The goal of this master’s program through these sets of experiments was to understand not only the production potentials of these two systems, but the financial aspects as well to determine economic viability in specific case scenarios. The Rotating Living Wall was tested through the growing of 12 varieties of microgreens. Experiments were performed from June 2014 to June 2015 to understand differences in seasonal yields, differences in yields based on variety of microgreen, yield comparison to a traditionally grown microgreen control group; both on a yields per/trough method as well as a yields per/ft.² method, rotational timing, moving versus stationary growth, differences in growth based on media depth, and differences in production yields from supplemental lighting. Performance criteria were based on measuring fresh weight, dry weight, height, and SPAD-meter readings (soil plant analysis development). Differences in yields throughout seasons were significant as well as differences between the Rotating Living Wall systems compared to the control group. The use of LED supplemental lighting provided significant differences in yields throughout winter season growing. Rotational timing, media depth, as well as physical movement of plants showed minimal or no significant influence on yields. By establishing the potential revenues and various costs that are part of growing with the Rotating Living Wall system, financial viability was analyzed showing that these systems can be profitable when used in State College, PA, within certain operating parameters. Living Furniture, which is a small scale aesthetic aquaponics system, was tested through the course of ten trials to understand not only the yield potentials for a variety of microgreens, but the operating costs as well. Number of fish and fish food mass did not result in significant differences in production yields with chelated iron supplementation, but did result in significant differences for water chemistry (specifically concentrations of ammonia, nitrite, and nitrate). Water chemistry overall did prove to be better in the Living Furniture systems compared to a control setup tank with a standard mechanical filter. Chelated iron supplementation resulted in significant improvement for overall production of the systems; even resulting in the aquaponic systems surpassing the production yields from control-grown microgreens produced in a commercial potting mix. The research completed throughout these studies has not only provided a base line of operation for both these systems, but has also given insight into future studies and research that can be completed for further optimization and increased efficiency. Developed and improved growing systems may have the potential to provide solutions for fighting food deserts and ultimately the big picture of world hunger.