Sustainability Assessment of Offshore Aquaculture System With Self-Sufficient Energy and Feed

Abstract Aquaculture is attracting considerable attention due to market growth and potential environmental benefits but traditional coastal aquaculture systems create pollution and threaten marine ecosystems. Hence, there’s a need for more environmentally-friendly aquaculture approaches. Also, the prices of fish feed are rising, impacting the cost of conventional aquaculture systems as well as energy price fluctuation. The multi-purpose platform integrating marine renewable energy production, fish aquaculture, microalgae cultivation, and processing facilities has been designed to be economically viable in subtropical regions. The platform ensures year-round electricity supply by using ocean thermal energy conversion technology and producing hydrogen during surplus electricity periods. The Inclusive Impact Index (Triple-I) is employed to evaluate the sustainability of the multi-purpose platform in comparison to conventional aquaculture. The results reveal that while conventional aquaculture may be more profitable, the Triple-I evaluation indicates its unsustainability. In contrast, the multi-purpose platform offers a substantial environmental advantage, despite its higher initial investment cost.