Energy Modelling to Evaluate the Thermal Regulation of Aquaculture Raceways using Geothermal Heat Exchange
Abstract
Raceways are used in the aquaculture industry to farm fish species that swim against an upstream current. Raceways often draw water from a large waterbody and hence, their temperature changes due to seasonal variation, which directly affect the production yield. This study investigates a novel approach to regulate the raceway water temperature in a sustainable way by utilizing geothermal energy exchange. Energy models were developed to simulate heat transfer in a geothermal borehole heat exchange system and in the raceway system. The two models were then coupled to simulate the thermal regulation of the raceway water via borehole heat exchangers. Results demonstrated that a raceway can be thermally regulated via a geothermal borehole system. The raceway temperatures, in some sites, were found to increase by up to 200% in winter months and decease by up to 17% in summer months, and consequently, increased the duration of optimal raceway temperature range by 100%-400% for some fish species.