AMMONIA - A LONG HAUL SHIPPING SOLUTION

You'll be hearing a lot more about ammonia as a clean fuel option as the race to zero carbon by 2050 progresses. In particular, it looks like a strong option for long-haul shipping and trucking. So what is it, how is it made, and how does it shape up as a green fuel?

Chemically, ammonia is a molecule comprising three hydrogen atoms, each linked to one central nitrogen atom. Both very common elements; the Earth's atmosphere is mostly nitrogen, and hydrogen is of course the most abundant element in the universe. That doesn't mean it's simple to produce, but we'll get to that.

At atmospheric pressure, ammonia is a very stinky gas with a boiling point of −33.3 °C (−28.0 °F). Kept cold or under a modest amount of pressure, it's relatively easy to liquefy, making it a much easier green fuel to transport and store than hydrogen. You can truck it about or keep it in tanks, cheap as chips. Hydrogen is nearly 30 times more expensive to store.

Indeed, in many ways, ammonia does a better job of storing hydrogen than hydrogen gas itself; H2 is notorious for leaking away through the metal walls of containers, for embrittling steel it comes into contact with, and for taking a lot of energy to liquefy at cryogenic temperatures. And then there's density: it may sound weird, but there's one and a half times more hydrogen in a gallon of ammonia than there is in a gallon of hydrogen, all else being equal - link - Loz Blain - link - more like this - link