BRIDGING THE GAP BETWEEN A LARGE-SCALE FUTURE AND THE SMALL-SCALE NOW: A HOLISTIC DESIGN FRAMEWORK FOR SEAWEED FARMING PLATFORMS

The US Department of Energy ARPA-e program has envisioned a large-scale future for seaweed farming in the United States via the MacroAlgae Research Inspiring Novel Energy Resources (MARINER). MARINER projects have developed innovative designs for large-scale, offshore seaweed farming, with the future aim of 100 ha unit farms. Ideally, these innovative designs and components thereof would transfer directly to the existing, albeit nascent, coastal seaweed farming sector in the USA. However, there is a clear discrepancy between the proposed large-scale farms and the scale of the existing seaweed aquaculture industry. In Maine for example, the majority of seaweed farms grow sugar kelp, Saccharina latissima, on farm leases that are limited to 37 m² (400ft²). These small operations are limited in capital and infrastructure and their needs are distinct from the MARINER-oriented design process, which is focused on maximizing offshore survivability and high production.

We have developed a holistic design framework for seaweed farm engineering to meet current industry needs and challenges. Our design uses pre-identified industry priorities categorized within three major focus points (Figure 1) to ensure functionality across the spectrum of uses. Our team at the University of New England has developed a scalable large-scale array system deployed at a 2 ha site in Saco Bay, Maine. As part of this design process, our team sought to both satisfy MARINER goals (scalability, offshore survivability, high production), and design a system to meet the needs of the growing inshore seaweed farming industry.