The engineering is relatively easy and already well under development in many countries.
What are far more difficult and not asked loudly enough, are the resulting environmental questions.
- One method, and arguable the "greenest", for producing the hydrogen is electrolysing water. The hydrogen is burnt in a conventional engine or used in a fuel-cell, and the exhaust is water. However, that electroysis needs a lot of electricity.
Questions: How much electricity and generated how, on a sufficiently large scale for the home nation and even for export to poorer neighbours?
===
- The batteries and generators both need sizeable quantities of so-called "rare-earth" metals. Some are also used in the electronic devices we are all being pushed to use more and more. These elements are not very rare geologically but suitable deposits of their ores, certainly are.
Presently most are in China or countries controlled by China and Chinese companies - and already the USA and much of the West is very heavily reliant on the People's Republic of China. More ore deposits are in Canada, parts of South America (ask China...) and possibly Greenland.
Greenland's ice-cover is melting away along with much of the Polar sea-ice, opening the Arctic lands and seas into a future of very great commercial and strategic significance. Studying a map of the Northern Hemisphere from vertically above the North Pole, is rather thought-provoking.
Questions: are there enough metals to go round? How stable will future supplies be? How recoverable are they from scrapping worn-out equipment?
===
I gather Denmark is already answering Q1; but Denmark is a physically small, mostly rural country with a fairly low population. She is embarking on building large-scale wind-farms that when electricity demand is low, will use the surplus electricity to produce hydrogen. Unlike electricity, gases are comparatively easy to store. The by-product is oxygen - valuable itself as a commodity, but otherwise can simply be released into the atmosphere.
I bet you know what jumped out at me immediately. CHINA IS IN CHARGE AND AHEAD OF US! OMG(osh)! Just what we need right? Being "very heavily reliant on the Republic of China" cannot be a good thing for anyone but China right? Has CHINA won the "best in foresight planning and execution" trophy already? If so we will always be at their mercy and beholden to them? We have barely begun the race and already lost? Did the way things being run the last 4 years in the US at least have anything to do with it? A lot? 4 Years ago where was China? Already ahead of us? OY vey! Do you worry about this at all? I mean what can be do about it? How can we catch up and even if we do isn't China still in charge? I guess we shall find out. Thank you for your fine reply Durdle. I can't say it makes me happy. Not your fault. You aren't the one creating the problem. You bare simply explaining it. And so it goes! I go back and forth all the time between :) and :(. Do you too?
This post was edited by RosieG at May 24, 2021 4:49 AM MDT
Durdle 