Construction of a Coastal Limestone Carrier with a Hybrid Propulsion System using aGas-Only Engine and a Battery
September 30, 2021
Nippon Steel Corporation
Nippon Steel Cement Co., Ltd.
NS United Naiko Kaiun Kaisha, Ltd.
Japan Petroleum Exploration Co., Ltd.
Tsuneishi Shipbuilding Co., Ltd.
Kawasaki Heavy Industries, Ltd.

NS United Naiko Kaiun Kaisha, Ltd. (President and Representative Director: Kazushi
Fukuda, Head Office: Chiyoda-ku, Tokyo hereinafter called "NSU Naiko"), Nippon SteelCorporation (President: Eiji Hashimoto, Head Office: Chiyoda-ku, Tokyo), Nippon Steel
Cement Co., Ltd. (President: Yasuhiro Hashimoto, Head Office: Muroran City, Hokkaido),
Japan Petroleum Exploration Co., Ltd. (Representative Director and President: MasahiroFujita, Head Office: Chiyoda-ku, Tokyo), Tsuneishi Shipbuilding Co., Ltd. (President: Sachio
Okumura, Head Office: Fukuyama City, Hiroshima Prefecture), and Kawasaki HeavyIndustries, Ltd. (Representative Director, President & Chief Executive Officer: YasuhikoHashimoto, Tokyo Head Office: Minato-ku, Tokyo) have agreed to construct a vessel with ahybrid propulsion system combining a gas-only engine and a battery (hereinafter called "thisVessel") as the replacement of the limestone carrier "Shimokita Maru" owned by NSU Naiko,and have today signed" Memorandum of Transportation contract," "Shipbuilding contract,""Gas-only engine and battery propulsion system sales contract," and "Liquefied natural gas
for marine fuel sales contract."<Conceptual image of this Vessel>

Gas fuel supplyBattery

Gas-only engine

This Vessel is scheduled to start the operation in February 2024, and will be equipped withJapan’s first gas-only engine and total 2,847 kWh lithium-ion battery. The LNG fuel tank isplanned to use 7% nickel steel plate developed by Nippon Steel Corporation for the first time
as a marine tank. The propulsion power and the onboard electric power during the sailing are
generated by the gas-only engine developed by Kawasaki Heavy Industries, Ltd. Only natural
gas will be used for high power, long distance, and long duration navigation. The propulsion
power and the onboard power during entering, leaving and berthing ports will be provided
from the battery to achieve zero-emission operation.
The CO2 emission reduction effect of introducing the propulsion system of this vessel is
23.56% (about 30% at normal load operation) compared to the conventional vessels of thesame type, and the exhaust gas of the gas-only engine contains almost no SOx, and NOxemissions is far below the TierⅢ standards.
In addition, on its main routes, the loading port, Shiriyamisaki(Aomori Prefecture) andthe unloading port, Muroran (Hokkaido), the zero-emission operations that are friendly tothe environment will be carried out.
The construction of this Vessel was adopted by the Global Environment Bureau of theJapanese Ministry of the Environment and the Maritime Bureau of the Japanese Ministry ofLand, Infrastructure, Transport and Tourism for the "Projects to promote the introduction ofadvanced technologies that will simultaneously achieve social innovation and thedecarbonization of logistics (Projects to promote the introduction of LNG fuel systems, etc.)"
FY2021 Subsidy for the expenses in projects for measures to suppress carbon dioxideemissions.

Overview of the successor ship to the Shimokita Maru
Deadweight tonnage (DWT): approximately 5,560 tons
Total length: approximately 93.8 m
Molded breadth: approximately 18.2 m
Molded depth: approximately 9.9 m
Scheduled Delivery: Early February 2024
Propulsion system: Hybrid system of gas-only engine (8L30KG) and battery
Shipyard: Tsuneishi Shipbuilding
Liquefied natural gas supplier: Japan Petroleum Exploration
Main route/Cargo: Shiriyamisaki - Muroran /Limestone<Roles of each company>
Shipcharterer：Nippon Steel Corporation and Nippon Steel Cement
Shipowner/Operator: NS United Naiko Kaiun Kaisha, Ltd.
Propulsion system: Kawasaki Heavy Industries

Shipyard: Tsuneishi Shipbuilding
Liquefied natural gas supplier: Japan Petroleum Exploration