Exergoeconomics of near-zero discharge RAS: Strategy for turbot farming
AQUACULTURE, cilt.626, 2027 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 626
- Basım Tarihi: 2027
- Doi Numarası: 10.1016/j.aquaculture.2026.744388
- Dergi Adı: AQUACULTURE
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Artic & Antarctic Regions, BIOSIS, Geobase, Zoological Record, Academic Search Ultimate (EBSCO), Natural Science Collection (ProQuest), Earth, Atmospheric, & Aquatic Science Collection (ProQuest)
- Karadeniz Teknik Üniversitesi Adresli: Evet
Özet
Recirculating aquaculture systems (RAS) are increasingly being promoted as environmentally sustainable production technologies. However, their high energy demand remains a major economic barrier to achieving commercial viability. This study applied an exergoeconomic approach to analyse cost formation and allocation in a commercial near-zero discharge RAS designed for turbot (Scophthalmus maximus) grow-out under Black Sea environmental conditions. Using the specific exergy costing methodology, unit exergy costs were assigned to the system components and product streams, enabling the quantification of monetary losses associated with thermodynamic inefficiencies. It was established that the process is controlled by operating costs. The results demonstrate that the operational exergy destruction cost rate (14.49 $/h) exerts a significantly greater impact on the system's economic performance than levelized capital costs (5.41 $/h), resulting in a low system-wide exergoeconomic factor of 27.2%. The unit cost of harvested turbot was determined to be 8.87 $/kg, with a corresponding specific energy consumption of 43.35 kWh/kg. The most critical internal factors were the hydrodynamic resistance in the recirculation cycle, temperature regulation in the chiller, and oxygen supply via oxygen generating and injection systems. Therefore, the circulation pump (22.66 kW), chiller (15.00 kW), and oxygen generator (14.89 kW) were the major thermodynamic and economic bottlenecks. Sensitivity analysis shows that fluctuations in electricity prices (in tariff from 0.10 to 0.25 $/kWh resulted in a change in unit costs from 6.70 to 13.21 $/kg) have a much greater impact on unit production costs than changes in capital investments. This research shows an actual way to allocate costs in RAS in order to make the right choices concerning the energy efficiency increase and cost management. It shows how exergoeconomics can improve the economic decision-making process in intensive aquaculture systems compared to traditional energy and cost analyses.