![Amogy's tug boat](https://images.newscientist.com/wp-content/uploads/2023/03/29215841/SEI_150163099.jpg?width=1200)
The Brooklyn Navy Yard’s sprawling industrial complex once employed 70,000 workers to build US battleships and aircraft carriers during the second world war. Almost 80 years later, it has become home to a New York City start-up with a very different maritime mission – harnessing ammonia as a low-carbon fuel for the global shipping industry.
The start-up Amogy has already shown how its ammonia-powered technology can work in a flying drone, a John Deere tractor and most recently a semi-truck. But the company thinks its best chance …