Europe often takes the spotlight for advancements in maritime industry electrification. Countries like Norway and Finland are already operating over a hundred electric vessels, driving the global shift toward sustainable shipping. Japan, on the other hand, has been comparatively quiet – with just around 10 electric vessels currently in operation.
But behind the scenes, Japan is making strides in electrification that could reshape the industry.
Automation first, electrification next high priority
Japan’s strategy reflects its unique demographic and economic context. With a rapidly aging population, the growing lack of sufficient crew members on vessels and fewer young people entering maritime professions, the focus has been on developing autonomous and remotely operated vessels.
More than 30 domestic companies are now collaborating with the Nippon Foundation to develop smart ship technologies like automatic berthing, remote monitoring and land-based operational support. Testing of autonomous operations has been carried out simultaneously on vessels such as container ships and small and large ferries. Practical applications include unmanned navigation of nearly 800 km in the Pacific Ocean, navigation in congested waters such as Tokyo Bay and highly accurate autonomous docking performance. Public and private sectors are working together to make at least 50% of domestic vessels autonomous by 2040.
The push for automation is not a substitute for electrification, however – it’s a parallel track.
More than JPY 120 billion (about EUR 700 million) in subsidies have been allocated to shipyards and marine equipment manufacturers to accelerate the development of zero-emission ships, particularly those running on ammonia, hydrogen and battery systems.
Overcoming barriers to marine electrification
Several key steps must be taken, however, before large-scale electrification can take off. The most critical is infrastructure development. Charging systems and fuel bunkering must first be developed at ports to support alternative energy sources.
Other steps include improving energy density of electrical solutions, reducing the price of lithium batteries and fuel cells and cutting inverter costs through mass production.
One reason shipowners and shipyards in Japan have been slow to embrace electric propulsion is the lack of real-world verification. Electromagnetic field analysis and circuit simulation alone often fall short of replicating the real-world behavior of the high voltages and large currents of power electronics.
Therefore, testing in environments as close as possible to real-world conditions is critical to resolve technical challenges and build the confidence needed for wider adoption.
GIRD: real-world testing for better products and broader acceptance
In November 2023, BEMAC opened GIRD, a full-scale testing facility for verifying electric propulsion systems under real-world conditions. Real-world measurement data is critical to product development as hybrid electric propulsion systems become ever more complex. It accelerates progress across the industry and supports broader acceptance.
One of the main objectives of GIRD is to improve the reliability of electric propulsion systems. Load tests, environmental simulations, environmental resistance tests and protective operations in ship-like operating conditions help improve ship propulsion and power supply systems, batteries, motors and power electronics systems.
GIRD makes possible the integration and testing of various powertrain components, including diesel engine generators, cooling chillers, lithium-ion batteries, battery simulators and back-to-back electric propulsion propeller load simulators. Although GIRD’s emphasis is on electric propulsion systems, environmental testing such as vibration and temperature chamber testing is also possible. The equipment includes a power supply system simulation and a resistive and inductive load device to change bus voltage and frequency.
Test results will be used to optimize designs for ship powertrain systems in particular, aiming for more compact, lightweight, efficient and reliable equipment. As hybrid electric propulsion systems become more complex, real-world measurement data will play a critical role in advancing product development. It will also enable design optimization, helping to boost efficiency and minimize system size and weight.
By supporting joint product development – such as testing the renowned The Switch DC-Hub – and other design improvements, GIRD is expected to boost productivity across the entire BEMAC group.
Some examples of our testing done for internal development so far include:
- Comparing the results of simulated electric ship bus voltage distortion caused by inverter harmonics with actual measurements
- Verification of the prototype DC1100 VSiC inverter for the 700 kVA-class motor drive
- Verification of capacitor reduction smoothing for DC/AC and DC/DC converters for 500 kVA-class shipboard power supply
- Verification of the in-house 60 kW-class water-cooling unit
GIRD also makes it possible to study real-world noise factors such as motor torque ripple, system vibration and ground currents from inverters, all key contributors to acoustic and electrical noise.
The challenge: solving EMC issues in electrified vessels
Reducing electrical noise is an ongoing challenge in power electronics. The increasing capacity of inverters and the installation of multiple inverters in close proximity are likely to complicate the issue as ship electrification increases.
In the future, inverters will likely be used not only in propulsion systems but also in auxiliary systems. On domestic ships where engine rooms and electrical rooms are small, the noise environment will worsen as the number of inverter devices increases. It will become even more important to reduce the effects of EMC noise as autonomous ships become a reality.
Adding sensors in engine rooms to collect data, optimizing suppression methods such as filters on the noise-generating side, and using shielding components, such as sensors to avoid malfunctions, are some of the options being explored.
GIRD plans to add a 3-meter anechoic chamber by March 2028 to study these solutions. The equipment will allow BEMAC to develop effective noise countermeasure technologies and incorporate them directly into electrical installations.
With a strong focus on EMC solutions for electrified ships, BEMAC, together with The Switch, is aiming to reach a new level of technological development: one that combines compact, lightweight and highly efficient systems with greater safety and reliability.
Developments from Japan
Japan’s thorough research and investigation of marine electrification complements Europe’s fast-paced deployment. Where Europe often leads with implementation, Japan may soon drive the refinements needed to scale these technologies scale reliably, safely and efficiently.
Together, BEMAC and The Switch are demonstrating that the marine industry’s electrification isn’t a one-size-fits-all path. It is a cooperative evolution driven by different regions solving different pieces of the puzzle.
Corporate Officer, Executive General Manager of Innovation Management Division
Komatsu Yuichi
Komatsu leads BEMAC’s Innovation Division, driving advancements in frequency converters, batteries, autonomous ship systems and dynamic positioning technologies. He joined BEMAC in 2019 after a career at Toshiba Mitsubishi-Electric Industrial Systems Corporation, where he developed electric propulsion and engineering systems for submarines, research and cable-laying vessels. He is a former chair of the Japan Electrical Manufacturers Association’s Rotating Machinery and Control Working Group. With research focused on laser-induced lightning and plasma generation, Komatsu holds a master’s degree in electrical engineering from Miyazaki University.