Case study

MINMARINE Shipmanagement GmbH & Co

Bulkcarrier Golden Grains achieves near immediate ROI after VICUSdt Express Analysis

The study carried out for MINMARINE Shipmanagement GmbH & Co. KG, German ship owner and manager focused on bulk carrier tonnage, shows improvement scenarios for the reduction of operating costs thanks to the hydrodynamic study and propulsive improvements carried out by VICUSdt that lead the Golden Grains vessel to recover the investment in record time.


MINMARINE has relied on one of VICUSdt’s Express Analysis services to improve the energy consumption and emissions produced by its MV Golden Grains, while improving its EEXI and CII index values. The study was conducted in October 2022 using different technologies, and the scope of work included data collection and calculation scenario analysis for the ship’s hydrodynamics and propulsion technologies.

Regarding hydrodynamics, the VICUSdt Express Analysis recommended adjusting the trim of the ship slightly towards the bow. With this change it is possible to reduce the resistance of the ship by 8-10%, although being a bulk carrier the application of this measure has many limitations.

On the other hand, in the area of fuel saving technologies, the conclusions were the following:

  • The installation of a finned propeller hood or rudder bulb would generate improvements of the order of 2%.
  • The implementation of an air lubrication system would offer a savings potential of ±10% depending on the type and cost of fuel.

In conclusion, the study on the Golden Grains shows that this vessel has the potential to significantly reduce its operating costs through various investment options that, in turn, ensure an almost immediate return. Specifically, the proposals offered by VICUSdt after the analysis were:

  • No cost: it is proposed, within the possibilities of the ship, to adjust the trim depending on the speed and load condition.
  • Minimal investment: installing rudder bulb or WAKEBULB cap which could lead to 2-5% fuel savings.
  • High investment: by implementing an air lubrication system that provides the greatest savings (±10%) regardless of the draft, trim or RPM of the shaft. The air lubrication system can be fully installed in 8-14 days.

All these options can deduce important economic improvements, since the installation times are low and, even in the case of greater investment, the amortization times are short, considering the savings in fuel and emissions.

WAKEBULB design by VICUSdt

The fabrication of the rudder bulb, as well as its installation, was carried out by the shipyard itself, where the planned docking was carried out following the plans and instructions of VICUSdt. Once the work was completed and verified by the classification society, the sea trials were carried out again where the improvements that this Spanish company had promised were confirmed.

The Golden Grains vessel is a 181-meter-long bulk carrier with a deadweight of 37,597 tons. By applying the proposals of the study carried out by VICUSdt, the return on investment has been achieved in a few months, providing a saving of 3%.