New Profile Technology (NPT) propeller, a decarbonization tool

The reduction of ENGINE POWER and operating rpm requires a newly designed propeller because the characteristics of the engine and the propeller have been matched at a different operating point. With the New Profile Technology (NPT)  propeller by Stone Marine Propulsion, a typical 2-6% gain in propeller efficiency can be obtained, due to the design of section’s characteristics (a more efficient blade profile).

Section Geometry & Design characteristics

As the benefit is provided by the section geometry (and not by the Blade tip) NPT can be of smaller diameter with significantly less weight, lower Blade Area Ratio and reduced Inertial moments.
The improved design characteristics of the new NPT propeller, feature lower pressure pulses, reduced cavitation, and noise, as it is verified by extensive measurements in water basins.

Propulsion Efficiency & Decarbonization Benefits

Our proposed design from Stone Marine Propulsion (SMP) with a lot of successful applications, guarantees an increase in the overall propulsion efficiency of about 2-4% from the existing propellers. The efficiency gain is not an abstract figure. It is related to lower engine fuel consumption and less load at the new Engine rating which can be regarded as a major Decarbonization tool.
Further improvements can be achieved through the Stone Marine Cap Fin, which can add an additional 1-2% efficiency gain.


The NPT has the same cost as a conventional propeller in the case of retrofitting since it can be partly compensated by the cost of recycling the existing propeller.