In the context of escalating energy demand and the pressing need for carbon neutrality to combat global warming, the exploration of alternative fuels for internal combustion engines becomes crucial. While hydrogen has been recognized as a clean fuel option, the article emphasizes the advantages of using ammonia as a superior alternative due to its higher hydrogen density, efficient storage, and clean combustion properties. Ammonia's complete combustion producing only water and nitrogen minimizes environmental impact, making it a promising candidate for clean engine technology. Research comparing various alternative fuels highlights ammonia as the most balanced carbon-free fuel, with extensive infrastructure and the potential for green production from renewable energy sources. Despite facing challenges in combustion technology, ammonia's unique properties, including a high octane number and low adiabatic flame temperature, position it favorably for future engine development. The historical use of ammonia in Belgium during World War II contrasts with the slow progress in modern research, where current efforts focus on overcoming combustion challenges through the utilization of accelerants like hydrogen. The projected global shift towards green ammonia production signifies a significant step towards sustainable energy sources and cleaner engine technology.