Classification society DNV has approved a new electric propulsion concept, ABB Dynafin, developed by engineering firm ABB.

The approval in principle (AiP) confirms the design is technically feasible and can move closer to commercial use, ABB said in a statement on its website on Thursday.

The propulsion system works differently from traditional propellers.

It uses an electric motor to drive a horizontal wheel at the stern, fitted with vertical blades.

The motion is similar to a whale’s tail, allowing the system to provide thrust and steering at the same time. Each blade is controlled by its own electric motor, removing the need for mechanical gearboxes.

ABB said early studies showed the system could reduce energy use by about 22% compared with a conventional shaft line.

With AiP in place, ABB said the system can be considered for vessels such as ferries, ro-ro ships and offshore support vessels.

The fully electric design is also compatible with batteries and fuel cells