INPEX opens CCUS-based ammonia demonstrator in Kashiwazaki City

“Local production for local consumption”

Click to expand. Diagram of the Kashiwazaki Hydrogen Park, recently opened by INPEX. Source: INPEX.

INPEX has officially opened the Kashiwazaki Hydrogen Park in Niigata Prefecture, Japan. Consisting of a CCUS-based hydrogen and ammonia demonstration plant, the Kashiwazaki Hydrogen Power Plant and the Hirai Gas Collection Station, the project is “Japan’s first to integrate the entire process from the production to the utilization of hydrogen and ammonia”. Gas-based hydrogen production began in June, with a portion to be used for ammonia production (500 tons per year) via Tsubame’s low temperature and low pressure ammonia synthesis technology. CO₂ emitted during hydrogen production will be injected into previously depleted gas reservoirs in the onshore Higashi-Kashiwazaki Gas Field. The project is also focused on local customers for each of the facility’s products: hydrogen, electricity, and ammonia.

The hydrogen production, ammonia production, and CCUS elements of the project are subsidized by the Japanese government agency New Energy and Industrial Technology Development Organization (NEDO). The implementation and evaluation of subsurface CO₂ storage is being conducted as a joint research exercise between INPEX and the Japan Organization for Metals and Energy Security (JOGMEC).

The project also adheres to the “local production for local consumption” concept focusing on Niigata Prefecture, where the Company has operated for many years. The natural gas used as a raw material is sourced from the Minami-Nagaoka Gas Field, which INPEX operates in another part of Niigata Prefecture. CO₂ generated as a byproduct during the production of hydrogen and ammonia will be injected (CCUS) into the reservoir of the Hirai area of the Higashi-Kashiwazaki Gas Field, where gas production has already ceased, reducing atmospheric emissions. The hydrogen produced in this project will be used to generate electricity, which will be supplied via a power grid to end users in Niigata Prefecture. In addition, a portion of the hydrogen will be converted into ammonia and supplied to customers residing in Niigata Prefecture.

Further project details, as reported in INPEX’s official press release, 21 Nov 2025