Introduction. Most of the production of grow-out salmon in Norway, takes place in traditional open net cages. However, with this production system, there has been several challenges , such as spread of sea lice and escaped farmed salmon, that have led to negative environmental impacts. To battle these challenges, the Norwegian government incentivised the development of new production systems, such as offshore and (semi-)closed systems. Several producers are also producing post-smolt or grow-out fish in land-based farms. These production systems play a key role in sustainable growth in the industry.
Traditional cages have a quite standardized design, with floating collars in plastic with nylon nets. It is estimated that around a third of the plastic used is recirculated. Even though there are many different technical solution and concepts within each production system, it is expected that the material and energy requirements will be larger. This may lead to a burden shift, with higher environmental impacts in other countries, linked to the production of materials, mainly plastics, steel, and concrete. It is important to investigate how the material and infrastructure demands changes, and the opportunities for circular economy for material use. Several of the new production systems have a higher energy demand than production in traditional cages, which may lead to a development of the national electricity grid. This research aims to map supply chains of novel production systems with a focus on types and amounts of materials, energy, and infrastructure requirements.
Method ological approach. This work is based on reviews of existing and planned production systems, peer reviewed articles on aquaculture production in (semi-)closed, land-based and offshore systems from different countries, and company reports and newspaper articles from Norwegian industry media.
Results and discussion. New production systems show promising potential in reducing sea lice levels and escapees, as well as utilizing area unsuitable for traditional aquaculture. Employing new production systems can change the aquaculture supply chains and will in most cases require more materials such as steel, plastic and concrete, and more energy per kg produced salmon than traditional systems do . This contributes to the overall sustainability of salmon and it’s important to investigate the implications of this shift to assess the overall environmental, social, and economic impacts of salmon production in novel production systems.
This research is part of the COMPAREIT project, and is funded by the Research Council of Norway (grant number # 319647)