Obayashi has been procuring part of hydrogen for supply to the construction site (Kobe, Hyogo Pref.) of Iwatani’s new training facilities by railroad transportation from its own green hydrogen plant for verification which is located at Kokonoe-machi, Kusu-gun (Oita Pref.) once a month since October of 2023. Switching most of the transportation route by truck to railroad, the company has decreased its CO2 emission by about 82% one way from 0.347 t to 0.062 t.

According to Japan Freight Railway, the railroad transportation of hydrogen under the control and standard of
The High-Pressure Gas Safety Act and Related Ordinance was the first domestic attempt as of December 2023.

Obayashi has been supplying electric power using a pure hydrogen fuel cell (5kW made by Panasonic) at the temporary field office of its construction site as part of demonstrative examinations to reduce CO2 emission.

The hydrogen to transport by railroad is generated from the water electrolyzer (made by Kobelco Eco-solutions) with one unit of hydrogen cylinder bundle consisting of 20 containers and filled by the compressor (made by Howden of metal diaphragm at 10Nm3/h) up to a pressure of 19.6MPa.

As the transporting volume at one time is set at less than 300m3, there is no requirement for the qualification of high-pressure gas transport oversight for truck drivers.
The hydrogen bundle after filling are tentatively stored at Eto Sangyo’s EBL hydrogen station for time adjustment and then transported to Nishi Oita Station for loading onto Japan Freight Railway containers of 12ft.

Regarding the time adjustment, Obayashi says “The cargoes kept at the cargo terminal station for two hours or longer are regarded as storage under the High-Pressure Gas Control Act, and qualifications are required for the people and places to handle it. So, we implement to keep cargoes tentatively until the arrival of cargo trains bound for Kobe City areas to enhance efficiency.”

The transportation of hydrogen by railroad will be continued until the construction of the new building is completed.