Seaweed aquaculture is increasingly recognized as a nature-based climate solution, with macroalgae contributing roughly 1.5 petagrams of carbon to global annual net primary production. Farm sediments can bury about 1.87 ± 0.73 tons of carbon dioxide equivalent per hectare per year—twice the rate of adjacent non-farmed areas. Yet scaling seaweed farming to the open ocean has been stymied by strong currents that prevent stable attachment and destroy the low-velocity conditions needed for growth, as well as dilute nutrients like nitrogen, phosphorus, and dissolved iron. Existing platforms either depend on scarce offshore infrastructure or cannot regulate local flow, leaving a critical gap in efforts to harness the ocean’s vast potential for carbon removal.
Researchers at Zhejiang University, with collaborators at Guizhou University and the Ningbo Innovation Center, have now published a study online on 28 September 2026 in Environmental Science and Ecotechnology (DOI: 10.1016/j.ese.2026.100769) introducing the Seaweed Origami-inspired Aquaculture System (Seaweed OAS). The system draws on the traditional Chinese huiwen (fret) pattern to fold flat panels into a 25-sided variant pentagonal unit; twelve such units assemble into a dodecahedron-like shell. Each module combines an origami-inspired shell, an internal nutrient space, a central buoyancy ball, and connection seats. Using computational fluid dynamics, laboratory and lake tests, and an open-ocean trial in the Philippine Trench region, the team evaluated flow regulation, stability, and global deployment potential.
The geometry proved to be the breakthrough. Simulations tested dimensionless scaling ratios (φ = a/R) from 0.28 to 0.56, identifying an optimal single-unit design at φ = 0.36. At a current speed of 2.0 m s⁻¹, this unit produced 2,607.7 cm³ of suitable growth volume—where suitable growth is defined as streamwise velocity ≤0.5 m s⁻¹—and the best single-unit result reached 2,791.6 cm³, 17 times that of a spherical reference. In a six-unit hexagonal array with 0.35 m spacing, total suitable volume reached 33,210.3 cm³ at 2.0 m s⁻¹, or 5,535.1 cm³ per unit, a 2.1-fold improvement over an isolated unit. The modules were 3D-printed with polylactic acid and water-soluble polyvinyl alcohol supports. Compression tests yielded a minimum peak load of 11,693 N against a predicted peak drag of 39.9 N, a safety factor of 293. In lake and Philippine Trench trials, the system stayed afloat and stable, even during wave impacts. Global mapping estimated 10,335 million hectares—28.5% of the global ocean—as potentially suitable.
The authors said the design turns an ancient folding idea into a practical marine tool. “By reshaping flow around each module, the system creates quiet microhabitats where seaweed can attach and grow, while the same module stores slow-release nutrients,” they said. They added that cooperative wake interactions can amplify performance: the optimized hexagonal array lets upstream units shield downstream units, increasing suitable growth volume per unit. Still, they cautioned that long-term cultivation outcomes, deep-ocean carbon storage, and the ecological effects of material degradation remain unverified and require field study.
If validated over longer deployments, the Seaweed OAS could support open-ocean seaweed cultivation for food, feed, biomaterials, and carbon sequestration. Its modular shell-core design may be deployed without existing offshore infrastructure, and connection modules with controllable degradation could eventually let the system break apart so carbon-rich biomass sinks to the deep ocean for long-term storage. Global suitability mapping suggests vast potential across marine areas, though shipping lanes, ice cover, temperature, nutrient ratios, flow speed, and marine protected areas must guide siting. The authors call for long-term offshore trials to quantify seaweed growth, structural durability, material ecotoxicity, and the fate and persistence of sequestered carbon. Such validation will be essential to determine whether this origami-inspired approach can truly scale as a viable carbon dioxide removal strategy.
