Hybrid-Electric Biomass Fuel Carrier by Mitsubishi

ROBOSHIP, a standard hybrid-electric propulsion vessel aiming to promote a vision for the future of ships.

Tokyo-based firm e5 Lab Inc. and Mitsubishi Shipbuilding Co., Ltd., have agreed to provide the design for “ROBOSHIP”. It is a standard hybrid-electric propulsion vessel aiming to promote a vision for the future of ships. Note that, it is accounted for a 499-tonne biomass fuel carrier, built by Honda Heavy Industries Co., Ltd. The widespread adoption of the futuristic ROBOSHIP has the potential to reduce CO2 emissions in the coastal vessel industry, and lessen the workload for crews.


ROBOSHIP utilizes a standard system package comprising the hardware for hybrid-electric propulsion, including; propellers, motors, switchboards, storage batteries, and generators, together with the software to safely and efficiently control this equipment. The system is able to handle a cargo ship of up to around 749 tonnes.

Features & Benefits

The ship foregoes conventional diesel engines that require fossil fuel in favor of a hybrid-electric system. Thus, comprise large-capacity storage batteries and generators to drive the propulsion motors. The adoption of Mitsubishi Shipbuilding’s high-performance twin skeg ship design lowers propulsion horsepower by more than 20%. Hence, reducing CO2 emissions during cruising. Additionally, allows the ship to navigate completely CO2-free during port operations such as; freight loading and unloading, pier docking and undocking, and entering or leaving port. The generators are capable of switching between eco-friendly fuels including; LNG, hydrogen, ammonia, biofuel, and synthetic fuel, allowing all operations, including navigation.

Additional benefits of the system include;

  • Reduced noise and vibration for greater comfort inside the vessel.
  • Less need for troublesome diesel engine maintenance by highly experienced and knowledgeable engineers
  • Improved steering capabilities that make pier docking and undocking operations easier, reducing the workload on the crew.

The vessel that will have this system is in the construction process by Honda Heavy Industries for Asahi Tanker Co., Ltd. After completion and handover in April 2023, the ship will operate as a biomass carrier for Aioi Bioenergy Corporation. Additionally, it will utilize communications and digital technologies to support the digital transformation (DX) of the coastal vessel industry.

Further Development

In the future, the mass production of ships equipped with this standardized system will have lower costs. Hence, it will accelerate the widespread adoption of electric propulsion vessels. The common use of hybrid vessels will allow the accumulation of feedback, based on actual navigation. Thus, supporting the maintenance and improvement of system quality.

Mitsubishi Shipbuilding, in its “MARINE FUTURE STREAM” growth strategy, has set goals for the decarbonization of the maritime economy.

Going forward, e5 Lab and Mitsubishi Shipbuilding aspire to be a solution provider for the issues facing the maritime industry. Thus, jointly creating value with stakeholders, with an emphasis on environmental, social, and governance (ESG) factors.

Source: MHI

See also: World’s First Green Autonomous Vessel