The world’s first ship powered by pure ammonia successfully completed its maiden voyage on Chaohu Lake in eastern China, according to an announcement by the National Science Center in Hefei on June 28, 2025.

What sets this vessel apart from previous experiments is its use of an internal combustion system that runs entirely on 100% ammonia fuel. This marks a significant step toward the direct industrial use of ammonia as a marine fuel.

Ammonia, a chemical compound made of hydrogen and nitrogen, has emerged in recent years as a promising alternative to petroleum in maritime transport due to its environmentally friendly properties. When fully combusted, it produces no carbon dioxide—only water vapor and nitrogen—making it an ideal option for reducing carbon emissions. Onboard the ship, ammonia is stored as a liquid in pressurized or refrigerated tanks and is then converted into gas before entering the engine.

The vessel, named "Anhui," was developed through a collaboration between the Energy Institute of the Hefei Comprehensive National Science Center and Shenzhen HiSow New Energy Technology Co. It is equipped with a 200-kilowatt high-speed gas internal combustion engine—equivalent to about 270 horsepower—alongside two 100-kilowatt electric propulsion motors and a twin-screw propulsion system. The ship has a full load capacity of 50 tons and a rated speed of 10 knots.

According to the institute, the ship achieved stable and complete combustion of pure ammonia fuel, with near-zero carbon dioxide emissions and effective control of nitrogen oxide byproducts. This achievement represents a major milestone in building a clean and low-carbon energy system for maritime transport and strengthens the potential for widespread use of ammonia and hydrogen fuels in both marine and land-based transportation in the future.

The project stands as a significant breakthrough in the path toward green shipping and aligns with China’s strategic goals to reduce emissions and achieve carbon neutrality in the coming decades.