Geothermal Water Component of Land-Based Fish Farm—A Case Study of the Sustainable Blue Economy Architecture

Geothermal water, as a by-product of renewable energy generation, can be appreciated as part of a sustainable Blue Economy in terms of resource effectiveness. This could be part of urban geothermal resource parks in the near future. City aquaculture integrated with urban farms running in a cascading model of energy and material consumption can provide an advanced energy-water-food nexus in densely populated areas, evolving into a refined Nature 4.0 habitat. This case study of the world’s first climate-controlled, closed salmon farm based on geothermal resources presents inclusive, water-sensitive design principles and resilient urban planning, where architecture brings aquatic ecosystems indoors. This is also an example of how to reduce investment risk and integrate geothermal development with sustainable, innovative fish farming based on water circulation systems (RAS) and digital technologies to sustain life-support systems. This greenfield project on Poland’s Baltic coast highlights the potential for geothermal investments, demonstrating that even low-temperature extracted water can serve as both a renewable energy source and a valuable resource. Having operated successfully for over a decade with positive certification, this model of efficient geothermal resource utilization appears to be well-suited for replication and broader implementation.