Climate change strains scarce water resources and food production infrastructure, necessitating establishment of sound scientific basis for operation of sustainable alternative food production methodologies - such as aquaponics, which promises high yield versus small footprint. In a climate (such as in Bloemfontein, South Africa) including temperatures below freezing, real-time aquaponics monitoring and control is necessary to mitigate thermal losses and to ensure sustainability of fish stock and bio-filter micro-organisms. The system thermal energy also needs sustainable supplementation during wintertime. This study/paper aims to address the problem of monitoring and controlling thermal energy in a medium sized aquaponics system, to ensure biological sustainability, especially during extreme cold weather events.
Required supplementation was determined and the aquaponics system described and quantified in terms of mass-flow power transfer by measuring loop differential temperature and flow rate. Cold front temperature data evaluation determined implementation suitability and -sustainability. Subsystem temperature contributions to the main reservoir, and their cumulative influence on the biological component, were considered.
Results indicate thermal supplementation enabled 1.3 °C temperature loss mitigation for a 42-kl water reservoir over a period of three days, offsetting severe system temperature decrease during a cold front event, and preventing organism mortality
Quantification of flow loop power transfer, and successful supplementation monitoring and control, demonstrates the approach and implementation merit in the Bloemfontein area. Wi-Fi-enabled online real-time data potentially facilitates incorporation into the concept of “Sustainable Smart Cities”.
