Fast forward fifty years and, thanks to major leaps in subsea robotics, the industry is on the cusp of a new era, with companies like The Metals Company (TMC) and Allseas leading the way.
Since the 1970s, these technologies have seen dramatic improvements, with many of the breakthroughs coming from the offshore oil and gas sector’s expertise in developing sophisticated deep-sea systems. And with the transition away from fossil fuels expected to sustain exponential growth in demand for base metals needed for the production of batteries, clean energy, and global infrastructure, these advancements are now being adapted for use in deep-sea nodule collection, enabling more efficient and lower-impact methods of mineral sourcing.
In partnership with its engineering partner, Allseas, a recognized offshore leader with decades of experience installing subsea pipelines and other deep-sea structures, TMC has been at the forefront of the industry’s progress. In 2022, the companies undertook the first pilot collection system test in international waters since the late 1970s, resulting in a historic campaign during which over 3,500 tonnes of nodules were lifted from depths of 4 kilometers.
COLLECTORS & HYDRAULIC SYSTEMS
Purpose-designed and built by Allseas, the robotic collector vehicle lies at the heart of TMC’s proposed operations. Using tracks to move across the seafloor, this state-of-the art vehicle incorporates hydraulic pickup nozzles which direct jets of seawater across the tops of the nodules to collect them without touching them, thereby minimizing ecosystem disturbance.
Though various technologies have been developed to collect nodules, after an extensive evaluation process Allseas determined that a hydraulic flow system offered the ideal combination of efficient nodule pickup and controlled sediment mobilization, two critical factors in ensuring both the environmental responsibility and economic viability of TMC’s proposed operations.

MINIMIZING ENVIRONMENTAL IMPACT
A key concern surrounding nodule collection is the creation of sediment plumes as the tracked collector traverses the seafloor. Contrary to speculation by activists and in the media, the test of the Allseas designed and built pilot nodule collector revealed that the plume stayed low and settled fast, confirming earlier findings by MIT that 92–98% of sediment remains within 2 meters of the seafloor. With this data in hand, Allseas is refining the collector and its diffuser system to further limit sediment transport.
LOOKING AHEAD
The advancements being spearheaded by Allseas and TMC represent a major step toward a more responsible and secure source of the critical minerals needed to transition the world away from fossil fuels, while also supporting the ongoing industrialization of developing nations. Their work is also laying the groundwork for future innovations in deep-ocean technology, potentially integrating AI and even more advanced robotics to further enhance both efficiency and environmental responsibility.
This story was originally featured in ON&T Magazine’s October/November issue. Click here to read more.