Natural gas pipelines do not handle embrittlement from H well.
https://www.sciencedirect.com/science/article/pii/S245232161...
https://www.sciencedirect.com/science/article/pii/S245232161...
Ammonia—one nitrogen atom bonded to three hydrogen atoms—may not seem like an ideal fuel: The chemical, used in household cleaners, smells foul and is toxic. But its energy density by volume is nearly double that of liquid hydrogen—its primary competitor as a green alternative fuel—and it is easier to ship and distribute. "You can store it, ship it, burn it, and convert it back into hydrogen and nitrogen," says Tim Hughes, an energy storage researcher with manufacturing giant Siemens in Oxford, U.K. "In many ways, it's ideal."
More details:
https://www.sciencemag.org/news/2018/07/ammonia-renewable-fu...
Presumably the vast deserts of the coastal Middle East could continue their dominance of energy if they converted solar to ammonia as well.
There have been major advances recently in small-scale (single-turbine) production of ammonia from just current, water, and air. It seems like a much better choice than hydrogen for everything except the next generation of aircraft.
Aircraft need high energy per unit mass fuel, and hydrogen is king, but tankage is huge, so hydrogen airliners would need to be lifting bodies to have room for the fuel tanks.
With strict EU directives already in place to reduce ammonia emissions, I can’t imagine farmers using more of it would ever be encouraged!
As the article points out:
Most of the world’s ammonia is synthesized using Haber–Bosch, a century-old process that is fast and fairly efficient. But the factories emit vast amounts of carbon dioxide (CO2).
However they have invented a gentler, greener alternative.
A reverse fuel cell uses renewable electricity to drive a chemical reaction that makes ammonia..
There are also a number of existing hydrogen pipelines in operation. One of which was first built in the the 30s.
Steel fatigues faster, but predictably so. Ultimately the pipes themselves are replaced with thicker material, but it can be done incrementally and along existing right of way.