Tugboats are an attractive application for electrification ; with their light load and propulsion power bringing a lot of traction power, compared to the size of the vessel. Running on battery as the main power source is ideal for an inner harbor working tug as it travels short distances for idling and can be easily charged. A tugboat which is fully electric-powered produces zero emissions, requires no fuel, and operates noiselessly. This results in a significant reduction in fuel consumption, compared to a diesel-powered tug.
Around the world, the trend towards zero-emission ports is growing. One good example is the Port of Los Angeles. The port has been awarded an unprecedented $412 million grant from the U.S. Environmental Protection Agency (EPA)’s Clean Ports Program to support the zero-emission (ZE) transition at the nation’s busiest trade gateway. It is clear that the technologies are available, and the investments are often driven by government directions.
At Danfoss, we have the technology to accelerate the zero-emission transition. In Japan, the mission for Daito Corporation, a subsidiary of Kawasaki Kisen Kaisha, Ltd., to build a new tug was clear: to improve operating efficiency, reduce emissions, tackle the fuel challenges of tomorrow and meet the 2050 IMO standards as “K”Line group. Kawasaki Kisen Kaisha, Ltd. (”K“ Line) is a leading Japanese shipping company that offers international maritime transport and logistics services. Established in 1919, it operates various type of ships such as bulk carriers, car carriers, and LNG carriers, building a global network. The company is also committed to environmental sustainability, striving for net-zero emission in 2050.
In November 2024, “K”LINE officially announced that its subsidiary, Daito Corporation (Daito) will be building an electric tugboat, an electric vessel (EV) powered by a large-capacity lithium-ion battery. Delivery is expected in April 2027, and Danfoss is proud to play a pivotal role in this project.
The electric tug features 2 x 1.46 MW high-efficiency permanent magnet motors, 2 x 1.58 MWh battery banks as the main source of electric power, and Danfoss heat exchangers. The tug will support net-zero greenhouse gas (GHG) emission goals without compromising its performance. It is designed for heavy-duty and high-power operations, enabling strong peak-power performance during towing or bollard pulling and minimal energy consumption when it’s in other operating modes.
Danfoss active front-end (AFE) drives are used to supply energy from the battery energy storage system (BESS) to the electric tug. The AC grid switchboard enables an efficient shore energy supply, while DC grid is important for efficient energy transfer between batteries, propulsion system, and other consumers on the EV tugboat. Thanks to the fully electric propulsion system from Danfoss Drives, the two systems can be connected and are designed with built-in redundancy for enhanced reliability of operations. In addition, the shore supply solution allows the electric tugboats to charge while waiting in the harbor.