This startup plans to power a tugboat with ammonia later this year

Young Suk Jo, 34, came up with a possible solution in an unlikely chemical: ammonia. Amogy, a startup Jo cofounded in 2020, is building systems that can use ammonia, typically a component of fertilizer, as a fuel to power trucks and ships. 

One of ammonia’s most attractive attributes is its energy density, meaning it can pack a lot of energy into a relatively small space. Liquid ammonia can carry about three times more energy than compressed hydrogen, a leading clean fuel today. 

For Amogy, the key to using ammonia in transportation is pulling it apart. One of the core technologies in the startup’s ammonia-to-power system is a chemical reactor called a cracker. This reactor breaks ammonia down into nitrogen, which can be safely released into the atmosphere, and hydrogen. That hydrogen can then be used in a fuel cell to produce electricity.

Ammonia cracking isn’t a new process, but Jo and his co-inventors developed a chemical catalyst that can help the reaction run at a lower temperature, allowing the process to be done onboard vehicles. The team also developed a reactor that can run more efficiently than the current standard, turning roughly 40% of the energy in the ammonia into electricity.

Amogy has demonstrated its technology in a range of vehicles, starting in 2021 with a small drone whose total power demand was about 5 kilowatts and progressing to a semi truck, which ran on the company’s technology in January 2023 and used about 300 kW on average. Jo has overseen this scaling process, retrofitting each vehicle to run using ammonia fuel.