Tokyo-based e5 Lab Inc. and Mitsubishi Shipbuilding Co. Ltd. are to provide a “Roboship” design for a 499-tonne biomass fuel carrier being built by Honda Heavy Industries Co. Ltd. They say the widespread adoption of the futuristic Roboship has the potential to both reduce CO2 emissions from coastal vessels and lessen crew workloads—a major concern in Japan, which has an aging maritime workforce.
Suitable for cargo ships up to around 749 tons, the Roboship utilizes a standard system package that includes electric propulsion hardware (propellers, motors, switchboards, batteries, generators) and the software to safely and efficiently control this equipment.
Instead of conventional fossil-fueled diesel engines, the vessel uses a hybrid system of 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 requirements by more than 20%, reducing CO2 emissions during cruising, and allowing 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 liquefied natural gas (LNG), hydrogen, ammonia, biofuel, and synthetic fuel, allowing all operations, including navigation, to be CO2-free.
Additional benefits of the system include reduced noise and vibration for greater comfort inside the vessel, less need for diesel engine maintenance by highly experienced and knowledgeable engineers, and improved steering capabilities that make pier docking and undocking operations easier, reducing the workload on the crew.
Future mass production of ships equipped with this standardized system promises lower costs, which will accelerate the widespread adoption of electric propulsion vessels.
The Roboship vessel that is being built by Honda Heavy Industries is set to be completed and handed over to Asahi Tanker Co., Ltd. in April 2023, the ship is expected to operate as a biomass carrier for Aioi Bioenergy Corporation.
It will also be equipped with the Marindows digital platform developed by Marindows Inc., utilizing communications and digital technologies to support the digital transformation (DX) of coastal shipping.