Autonomous underwater maintenance dredger (AUMD)

Dredging is an energy-intensive process, requiring power to maintain forward speed as the drag head is trailed over the seabed, and powerful pumps to drive sediment and sand to the surface. The design challenge was to reduce both of these power requirements, and the result is our innovative AUMD.

Being submerged, our vessel operates closer to the seabed which reduces power requirements. The suction head of the AUMD’s dredge pump is reduced from 35 meters to 6 meters and its dredge pump power is reduced by 80% comparatively. In terms of propulsion power, the AUMD dramatically reduces wave-making and wave-breaking resistance, and so requires 55% less energy than its traditional counterpart.

In a C-Job comparison study between the 80-meter long AUMD and a conventional 104.6-meter long trailing suction hopper dredger (TSHD), the two dredgers provided the same dredging performance.

A 16 MWh battery pack is all the AUMD needs to be able to perform 12 hours of continuous dredging operations, making it ideal for maintenance in port environments. It is not only clean and sustainable, but also delivers substantially lower operating costs when compared to traditional dredgers.

Even applying a conservative estimate, C-Job found that AUMD owners could expect nearly twice as much profit after 15 years, with the higher initial investment offset by far lower operational costs. This return on investment makes an autonomous solution a real option for companies to consider.