Recirculating Aquaculture Is Possible without Major Energy Tradeoff: Life Cycle Assessment of Warmwater Fish Farming in Sweden

• Published in: Environmental science & technology 2020-12, Vol.54 (24), p.16062-16070
• Main Authors: Bergman, Kristina, Henriksson, Patrik J. G, Hornborg, Sara, Troell, Max, Borthwick, Louisa, Jonell, Malin, Philis, Gaspard, Ziegler, Friederike
• Format: Article
• Language: English
• Subjects: Animal Feed - analysis; Animals; Aquaculture; By-product utilization; Clarias; Climate change; Energy and Climate; Energy consumption; Energy demand; Energy management; Environmental assessment; Environmental challenges; Environmental impact; Environmental management; Environmental performance; Environmental pressures; Eutrophication; Fish farms; Fisheries; Global perspective; Increasing production; Land use; Life cycle; Life cycle analysis; Life cycle assessment; Life Cycle Assessment (LCA); Life Cycle Stages; Life cycles; Oreochromis; Recirculating aquaculture system; Seafood; Sustainable development; Sustainable food systems; Sweden; Tilapia; Water quality
• ISSN: 0013-936X; 1520-5851; 1520-5851
• DOI: 10.1021/acs.est.0c01100

Seafood is seen as promising for more sustainable diets. The increasing production in land-based closed Recirculating Aquaculture Systems (RASs) has overcome many local environmental challenges with traditional open net-pen systems such as eutrophication. The energy needed to maintain suitable water quality, with associated emissions, has however been seen as challenging from a global perspective. This study uses Life Cycle Assessment (LCA) to investigate the environmental performance and improvement potentials of a commercial RAS farm of tilapia and Clarias in Sweden. The environmental impact categories and indicators considered were freshwater eutrophication, climate change, energy demand, land use, and dependency on animal-source feed inputs per kg of fillet. We found that feed production contributed most to all environmental impacts (between 67 and 98%) except for energy demand for tilapia, contradicting previous findings that farm-level energy use is a driver of environmental pressures. The main improvement potentials include improved by-product utilization and use of a larger proportion of plant-based feed ingredients. Together with further smaller improvement potential identified, this suggests that RASs may play a more important role in a future, environmentally sustainable food system.