110V infrastructure for a Japanese 3D-printed Ozare 5.0 sloop

For a special international project, Robust-MT Marine Technology BV approached to design and build the complete electrical installation for an innovative 3D-printed Ozare 5.0 sloop. This vessel was destined for the World Expo in Osaka, Japan. This project presented a unique technical challenge rarely encountered within Europe: the vessel had to be fully equipped with a specific 110V onboard infrastructure to connect to the Japanese electricity grid.

Customer's wish

The pre-established specifications for this export project were extremely strict due to the planned deployment on the world stage in Japan and the long intercontinental transport duration. In addition, the initial design presented an extra challenge. The key criteria for this installation included:

Fully redundant system

The absolute necessity of a backup powertrain to rule out downtime during the World Expo.

Optimization of the underwater hull

The original hull shape of the sloop resulted in mediocre handling characteristics. On our advice, the underwater hull of this model has been completely revised and optimized for electric propulsion and improved maneuverability.

110V charging infrastructure

The obligation to be able to safely and efficiently charge the complete battery pack via the 110V mains voltage standard in Japan.

Certified export engineering

Fully preparing the entire boat for seaworthiness and logistically making it ready for transport in a sea container.

The solution

To meet the unique 110V requirement and the desired operational reliability, our engineering team designed a customer-specific system. Before proceeding to the final outfitting, we first extensively tested the new hull shape with a compact ePropulsion Spirit 1.0 Plus. The modified hull performed above expectations.

Following this successful test phase, the final installation was assembled. A unique feature of this project is that we fully assembled all electrical components, fuses, and distribution boards within a modular, waterproof cabinet. This compact and sleekly finished housing optimally protects the vulnerable electronics against moisture and saltwater.

Drive

A primary ePropulsion Navy 6.0 Evo system (6 kW). To guarantee absolute redundancy, a complete extra Navy 6.0 motor, including a second controller and an extra backup battery, has been supplied and installed.

Energy Storage & Charging

The battery bank and the associated ePropulsion chargers have been completely modified and certified by us for a 110V power supply. This ensures that the battery pack can be connected directly and safely to the local mains voltage in Japan.

Transport preparation

After the successful testing phase and sea trial, the entire boat was personally and expertly packed into a sea container by our team to ensure damage-free shipment to Asia.

Result

The electrical installation of this Ozare 5.0 sloop was successfully assembled in our workshop in Monster and extensively tested in practice during the sea trial. Thanks to the revised underwater hull, the sloop possessed excellent handling characteristics. Furthermore, the modular, watertight enclosure ensured an unprecedentedly sleek and safe interior finish.

Although the collaboration with the client was subsequently terminated and we have not received formal feedback regarding the operational deployment in Osaka due to a lack of further communication, this project has definitively confirmed Robust-MT's expertise in complex, international export engineering, hull optimization, and non-standard mains voltages (110V).