IHI Motor Launches Demonstration Test of Ammonia-Fueled Reciprocating Engine for Land-Based Power Generation

IHI Motor Co., Ltd. (hereinafter "IHI Motor"), a member of the IHI Group, has installed and commenced operation of a land-based power generation demonstration plant centered on a 6,000kW-class ammonia-fueled engine at the IHI Motor Ota Factory (Ota City, Gunma Prefecture). Building on its pioneering technologies developed for marine ammonia-fueled engines, IHI Motor is developing ammonia-fueled reciprocating engines for land-based power generation, targeting an ammonia fuel ratio and GHG (greenhouse gas) reduction rate of over 90%. This demonstration test will verify the safety and operability of the entire power generation system, including auxiliary equipment. The test is scheduled to be completed by fiscal 2026, with commercial sales planned for fiscal 2027.

Exterior view of the demonstration plant

The IHI Group is expanding the ammonia value chain by advancing both ammonia supply chain development and fuel utilization technologies. In addition to converting boilers at thermal power plants to ammonia fuel and developing ammonia-dedicated gas turbines, the Group aims to expand power solutions that meet the decarbonization needs of domestic and international customers by deploying ammonia-fueled reciprocating engines into the land-based power generation sector.

This power generation system is intended for deployment not only as a power source for domestic industries but also for international and domestic remote islands, data centers, mines, and industrial parks—customers requiring more efficient, low-carbon power sources. In particular, it aims to create demand for ammonia fuel as a step-by-step decarbonization option for existing diesel engine power generation facilities currently using heavy or light oil.

The engine being tested at this demonstration facility is a land-based ammonia-heavy oil dual-fuel engine scaled up to the 6MW class, based on the 1.6MW-class 28ADF (developed as the main engine for coastal vessels). The design includes a V-type engine configuration and incorporates power generation control technologies developed through the 25ADF project for marine auxiliary engines. The engine can operate in both ammonia combustion mode and heavy oil-only mode, with targets of achieving over 90% in both ammonia fuel ratio and GHG reduction rate.

The demonstration test will verify not only the performance of the ammonia-fueled engine itself but also the safety and operability of the entire power generation system, including fuel supply equipment, exhaust after-treatment systems, and leak countermeasures. With practical application in mind, the system uses an enclosure designed for flexible installation and space-saving, and includes a safety system that contains any ammonia leakage within the enclosure and neutralizes it—ensuring a system that customers can use with confidence.

Looking ahead to the expansion of ammonia utilization in land-based ammonia engines beyond the 2030s, IHI Motor aims to contribute to the early expansion of the IHI Group’s ammonia value chain by creating both ammonia utilization technologies and fuel demand. Furthermore, in the future, the company will also work on developing dedicated ammonia-fueled engines to achieve zero CO2 emissions.

(*1) The 28ADF is an ammonia co-firing engine developed as the main engine for the world’s first commercially viable ammonia-fueled tugboat, "Kai." The first unit was delivered in February 2024, the tugboat was completed in August of the same year, and the demonstration voyage was successfully completed in March 2025. The ammonia co-firing ratio and GHG (greenhouse gas) reduction rate both exceeded 90%, reaching a maximum of approximately 95%. The concentrations of ammonia and N2O (nitrous oxide) in the exhaust were reduced to nearly zero after the exhaust after-treatment system. The research and development of both the 28ADF and 25ADF engines were conducted with support from the Green Innovation Fund project of the New Energy and Industrial Technology Development Organization (NEDO), a national research and development agency.

[Related URLs]

Press Release, March 28, 2025

World’s First Commercially Viable Ammonia-Fueled Tugboat "Kai" Completes Demonstration Voyage

Press Release, February 24, 2026

Development of Marine 4-Stroke Ammonia-Fueled Engine Wins 60th Japan Society of Mechanical Engineers' Minister of Economy, Trade and Industry Award