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Driving efficiency across RoRo and PCTC fleets

Roll-on/roll-off vessels (RoRo) and Pure Car and Truck Carriers (PCTC) are an important focus for Silverstream and a growing part of our portfolio. Our longstanding partnership with Grimaldi Group is testament to the effectiveness of the Silverstream® System in reducing fuel consumption and emissions in real-world operations.

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Proven performance and long-term partnerships in RoRo and PCTC

RoRo and PCTC vessels are well-suited to benefit from air lubrication. Their relatively flat-bottomed hull forms offer an ideal surface for a uniform layer of microbubbles, reducing frictional resistance and improving overall vessel efficiency. We also offer a tailored solution for PCTCs to ensure an optimal fit for our air release units. Operating on regular schedules with frequent port calls and varying speeds, these vessels are ideal candidates for the Silverstream® System’s proven performance across a wide range of operational profiles.

Our collaboration with Grimaldi began in 2018 and has grown to include 16 operational vessels and 10 more in progress. For Grimaldi’s GG5G-class RoRo vessels, we have delivered proven net fuel and emissions savings of 5–6%, contributing meaningfully to their sustainability goals.

The system also supports compliance with key environmental regulations. It helps operators meet Energy Efficiency Design Index (EEDI) and Energy Efficiency Existing Ship Index (EEXI) requirements for both newbuilds and retrofits, while also improving Carbon Intensity Index (CII) ratings – increasingly important for long-term fleet performance and, for PCTCs, charter competitiveness.

Unlock the benefits of the Silverstream® System

Our patented and fuel-agnostic Silverstream® System creates a uniform carpet of microbubbles that cuts frictional resistance between a ship’s hull and the water. This dramatically reduces fuel consumption and associated emissions, delivering between 5-10% proven net fuel and emissions savings, depending on vessel type. Our savings have been verified by independent third parties, including Lloyd’s Register, HSVA, the University of Southampton, Carnival and Shell. 

Control and Monitoring System

Control and Monitoring System

The Control and Monitoring System (CMS) for the Silverstream® System comprises the main Control Cabinet, which includes the processing unit, and at least one workstation which is either mounted to the CMS panel or installed in a location defined by the customer. Additional Workstations can be positioned in other locations around the vessel depending on design requirements. The CMS interfaces with the ALS plant as well as shipboard systems. The workstation is the primary Human Machine Interface (HMI) for operation of the ALS. In addition to the main ALS workstation, portable workstations can be connected to the Ethernet control network at locations requested by the owner to act as an additional HMI.

Air Compressors

Air Compressors

The ALS utilises a set of low-pressure oil-free volumetric compressors, mostly of the helical screw type, which generate a constant volumetric flow for a given speed of motor operation. Each compressor is powered through a VSD-controlled motor. The compressor speed is controlled by the Silverstream® System and varies depending on the vessel’s draught and speed.
Each compressor supplies air to two (2) ARUs. The location of the compressors is decided depending on the position of the ARUs, the existing piping arrangements and piping that potentially needs to be installed. They are arranged in such a manner that they are as evenly distributed as possible between the port and starboard sides of the vessel.

Air Release Units

Air Release Units

An Air Release Units (ARU) is a proprietary discharge unit that penetrates the hull and releases air fed through the Silverstream® System pipework into the water stream. As the vessel sails, the ARUs generate a carpet of microbubbles which reduces the vessel’s frictional resistance. The ARUs are built using structural steel, fabricated in accordance with Class requirements. They are arranged in a pattern, determined during the design phase, and are integrated into the bottom structure towards the bow.

Air Balancing Module

Air Balancing Module

The air balancing module is a custom fabricated galvanised steel component for the Silverstream® System that distributes air from the compressor to both ARU branches. Flanged bosses are welded for the drain valve, level sensor and spares that are blanked to allow for troubleshooting.

Control and Monitoring System

Control and Monitoring System

The Control and Monitoring System (CMS) for the Silverstream® System comprises the main Control Cabinet, which includes the processing unit, and at least one workstation which is either mounted to the CMS panel or installed in a location defined by the customer. Additional Workstations can be positioned in other locations around the vessel depending on design requirements. The CMS interfaces with the ALS plant as well as shipboard systems. The workstation is the primary Human Machine Interface (HMI) for operation of the ALS. In addition to the main ALS workstation, portable workstations can be connected to the Ethernet control network at locations requested by the owner to act as an additional HMI.

Air Compressors

Air Compressors

The ALS utilises a set of low-pressure oil-free volumetric compressors, mostly of the helical screw type, which generate a constant volumetric flow for a given speed of motor operation. Each compressor is powered through a VSD-controlled motor. The compressor speed is controlled by the Silverstream® System and varies depending on the vessel’s draught and speed.
Each compressor supplies air to two (2) ARUs. The location of the compressors is decided depending on the position of the ARUs, the existing piping arrangements and piping that potentially needs to be installed. They are arranged in such a manner that they are as evenly distributed as possible between the port and starboard sides of the vessel.

Air Release Units

Air Release Units

An Air Release Units (ARU) is a proprietary discharge unit that penetrates the hull and releases air fed through the Silverstream® System pipework into the water stream. As the vessel sails, the ARUs generate a carpet of microbubbles which reduces the vessel’s frictional resistance. The ARUs are built using structural steel, fabricated in accordance with Class requirements. They are arranged in a pattern, determined during the design phase, and are integrated into the bottom structure towards the bow.

Air Balancing Module

Air Balancing Module

The air balancing module is a custom fabricated galvanised steel component for the Silverstream® System that distributes air from the compressor to both ARU branches. Flanged bosses are welded for the drain valve, level sensor and spares that are blanked to allow for troubleshooting.

RoRo & PCTC testimonials

“Finnlines has chosen Silverstream Technologies based on their extensive experience, since they have invested significantly in research and development. We look forward to collaborating with them in future.”

Mikael Lindholm

Head of Newbuilding Department, Finnlines

Explore some of our key RoRo and PCTC projects

Explore our installations across key vessel segments and see how the Silverstream® System could benefit your fleet.

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Speak to our expert for RoRo & PCTC

Find out more about our latest RoRo and PCTC projects

Talk to Gilberto Zambrini
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