IHI Power Systems in July began operating a demonstration plant using a 6,000kW ammonia-fueled reciprocating engine at its Ota Plant in Gunma Prefecture. The engine uses ammonia and heavy fuel oil in a dual-fuel configuration and can also operate entirely on heavy fuel oil. The company is targeting both an ammonia fuel ratio and a greenhouse gas emissions reduction of more than 90%.
The demonstration will evaluate the complete power generation system, including engine performance, fuel supply equipment, exhaust aftertreatment, leak detection and safety controls. Fuel handling and exhaust treatment are particularly important because ammonia is toxic and can produce unburned ammonia and nitrous oxide under certain combustion conditions. IHI Power Systems plans to complete the testing during fiscal 2026 and begin commercial sales in fiscal 2027.
The 6 MW unit is based on the 1.6 MW 28ADF ammonia-fueled engine developed for coastal vessels and has been scaled up to a V18 configuration for stationary power applications. It also incorporates power generation control technology developed for auxiliary marine engines.
IHI Power Systems is targeting industrial power generation, remote islands, data centers, mines and industrial parks. The system will be marketed as an option for replacing or upgrading existing diesel and heavy-fuel-oil generating equipment.
Source: IHI
PSR Analysis: The significance of this announcement is that ammonia engine technology developed for marine applications is now being extended into the land-based stationary power market. Rather than developing an entirely new engine platform, IHI Power Systems is scaling up a 1.6 MW engine that already has operating experience on a commercial vessel. This should allow the company to apply its existing knowledge of combustion control, fuel supply, exhaust treatment and ammonia safety to the land-based system.
The initial product will use a dual fuel configuration rather than operating exclusively on ammonia. The ability to switch to heavy fuel oil means that power generation can continue if ammonia is unavailable or if a problem occurs with the ammonia-related equipment.
For mines, remote islands, industrial parks and data centers, where continuity of power supply is essential, fuel flexibility is likely to be an important consideration when evaluating the system.
Commercialization will involve more than the engine itself. An ammonia-based generating plant also requires fuel storage and supply equipment, leak detection, ventilation, safety controls and exhaust aftertreatment. Because ammonia is toxic and corrosive, additional specifications will also be required for piping, seals, valves and other fuel-handling components. The development of ammonia power generation could therefore create demand for engine manufacturers, and for suppliers of auxiliary equipment, control systems, exhaust treatment and fuel-handling equipment.
The commercial outlook will depend heavily on the price and availability of ammonia. Even if the engine performs as planned, the addressable market will remain limited if the cost of the fuel, storage equipment and safety systems is substantially higher than that of conventional diesel generation. Initial demand is therefore more likely to come from large industrial users that operate generating equipment for long periods, consume significant volumes of fuel and have both the financial capacity and a clear reason to invest in lower-carbon alternatives.
IHI Power Systems’ plan to begin commercial sales in fiscal 2027 indicates that ammonia-fueled reciprocating engines are moving beyond the research stage toward a defined product offering. The next points to watch will be continuous operating performance, maintenance intervals, the durability of the exhaust aftertreatment system, and the location and fuel supply arrangements of the first commercial installation. PSR
Akihiro Komuro is Research Analyst, Far East and Southeast Asia
