Techno-economic analysis of a recirculating tilapia-lettuce aquaponics system

Recirculating aquaponics systems (RAS) are known to provide an economic alternative for producing healthy foods to address health disparities and food scarcity in abandoned urban areas (food deserts) with limited water and land resources. This study integrated design and operational data into a techno-economic analysis (TEA) to study the profitability of a commercial-scale tilapia-lettuce aquaponics system in the U.S. Midwest. An operational pilot-scale plant was used to obtain the necessary data for the TEA modeling. A mid-size commercial system with a 5300 L fish tank and a 62–63 m2 plant grow bed space was considered for the analysis. The initial investment cost of the system was $69,230–69,600, with the greenhouse constituting 42% of the cost. The annual operating expense was $33,100 - $33,300, with labor being the major contributor (52%). Sensitivity analysis was performed on land, equipment, feed, utility costs and revenues from fish and lettuce, which identified the labor and greenhouse costs as prime factors controlling the profitability. The market value of the lettuce and its grow space used contributed to the profitability of the studied RAS from the revenue side. A cash flow analysis showed that the system can be profitable, offering a positive net present value (NPV) of $9000 - $12,220. Automated water quality monitoring further reduced labor costs, increasing NPV to $52,220 – $55,545. The TEA, augmented with process data and an uncertainty-based financial performance evaluation identifying key plant parameters, may serve as a framework for evaluating the economic viability of similar food production systems in different locations.