On 28 November, the christening and handover ceremony for a liquefied CO2 transportation demonstration test ship took place at the Shimonoseki Shipyard of Mitsubishi Heavy Industries, Ltd. The ship will be used in several research projects conducted by the Japanese New Energy and Industrial Technology Development Organization (NEDO).

The ship, named Excool, will transport liquefied CO2 for the carbon capture, utilisation and storage (CCUS) R&D and Demonstration Related Project, the Large-scale CCUS Demonstration in Tomakomai, the Demonstration Project on CO2 Transportation and the R&D and Demonstration Project for the Marine Transportation of CO2. NEDO conducts all these projects.

Also read: Yara to ship captured CO2 to Norway for subsea storage


The Excool has been delivered to Sanyu Kisen (Kobe City) and chartered to Nippon Gas Line. The ship will be operated in this demonstration project with the aim of establishing a technology for the large-volume and long-distance marine transport of liquefied CO2, which will play an important role in the development of Japan’s CCUS project.

The vessel will be used to verify the techniques for transporting and handling liquefied CO2 in tanks under different transport conditions.

The use of vessels is an effective way to improve the efficiency of transporting CO2 from capturing sites to remote storage sites. To increase efficiency still further, liquefied CO2 should be transported by large size vessels. Excool (EX-CO2L) was named with a determination to establish a safe operation technology for transporting low-temperature liquefied CO2, which is suitable for larger vessels.

General specifications of the ship are:

  • Cargo tank capacity: 1450 m3
  • Overall length: 72.0 m
  • Breadth: 12.5 m
  • Draft: 4.55 m

Also read: First CO2 storage project in the Netherlands kicks off


CCUS is regarded as an indispensable technology for achieving carbon neutrality in 2050, and the Japanese government and companies are preparing for it to become fully operational from 2030. Along with these activities, international movements are underway to utilise the abundant overseas CO2 storage capacity potential, including the establishment of the “Asia CCUS Network.”

The efficient transport of CO2 captured in Japan to overseas locations by ship will consequently become an essential technology in the future.

Partner companies

The roles of each company in this demonstration project are as follows:

  • Engineering Advancement Association of Japan (ENAA) has been engaged in research and development for the operation of a demonstration ship equipped with a liquefied carbon dioxide ship tank system. It achieved delivery of the demonstration vessel. ENAA will continue to be responsible for the planning, analysis and supervision of the demonstration test in the future.
  • Ochanomizu University conducts basic research on the control of the state of carbon dioxide (phase changes) and provides the information required for safe transportation.
  • Kawasaki Kisen Kaisha, Ltd. (“K” LINE) has helped to prepare an operation manual by conducting a risk assessment of the Excool using its expertise in operating cryogenic liquefied gas carriers. “K” LINE will continue to contribute to the establishment of safe liquefied CO2 carrier operation technology through its analysis of demonstration data.
  • Utilising its expertise in operating coastal gas carriers, Nippon Gas Line will measure CO2 temperature, pressure, flow, and other data while operating the Excool to develop optimal transport methods and cargo handling techniques.

Also read: Approval in principle for MOL’s Large Liquefied CO2 carrier design