TETRAS addresses a common challenge across the Baltic Sea Region: how to harmonize economic development with social and environmental goals.

Recirculating aquaculture systems (RAS), though not a novel concept, have gained remarkable significance in recent years, especially in the Baltic, where fish production in the marine environment is limited by environmental conditions. The initial need to prove the concept of producing high-quality shrimp or fish in closed land-based aquaculture systems has transitioned into a phase focused on scalability, economic viability, and environmental performance.

On their own, RAS are energy-intensive and expensive production systems. However, when placed strategically or coupled with other industries and processes, RAS have the potential to increase resource use efficiency and improve economic and environmental performance.

TETRAS aims to demonstrate new concepts of industrial symbiosis, where one process’s waste or residual becomes another process’s resource. The project revolves around four pilots working on different water solutions, each tackling unique challenges of RAS and complementing each other: treatment of RAS discharged water to be used as technical water for other industries, use of geothermal resources in RAS, best use of land and resources for a fully circular agro-industrial park, and a small-scale RAS for aquaculture awareness.

The project results will be summarised in a portfolio of solutions with recommendations for decision-makers, including:  investment-ready business cases, licensing, permits, and regulation guidelines, communication material for end-users and consumers, technical recommendations to future developers and innovators, non-technical recommendations for decision-makers on how to best support technology transfer, innovation, and market access to RAS and associated symbiotic concepts. These tools will enable public authorities to integrate RAS into regional development strategies, contributing to the sustainable use of aquatic resources and the transition to a circular blue economy in a win-win scenario.