Published 2018-03-15
Abstract
The University of Florida Institute of Food and Agricultural Sciences, Extension Orange County, maintains a 3-acre demonstration area called the “Exploration Gardens,” containing seven themed horticultural gardens. Among these is a quarter acre Small Farm and Home Demonstration Garden. Vegetable growing techniques for both commercial and home applications are on display including raised beds, grow boxes, floating raft, vertical stacked, and nutrient flow technique (NFT) hydroponic systems, as well as square foot and container gardens. The vertical and NFT hydroponic systems require electricity to provide daily fertigation. The nearest electrical box is 700 feet away, so it was decided to add solar electric panels to power the recirculating pumps. The vertical stacked (Verti-Gro® and Hydro-StackerTM) systems receive intermittent fertigation requiring an alternating current (AC) timer, charge controller, inverter and battery. The recirculating NFT systems use direct current (DC) power with the solar panels connected to a DC marine bilge pump with only a small charge controller in between. The NFT system operates continuously during sunlight hours. These systems will be described in detail. One NFT system was placed over an aquaculture tank in an onsite greenhouse and is receiving water and supplemental nutrients from the fish tank. Results of heirloom tomato and minicucumber variety trials in the greenhouse NFT aquaponic system will be discussed. Solar power offers opportunities for growers to produce hydroponic vegetables “off the grid,” with easily applied setup and maintenance techniques and provides Extension Agents a resource for teaching renewable energy applications.