I had the privilege of talking to a big investor in hydrogen fuel a few months ago so my answer will focus on hydrogen as a substitute for fossil fuels rather t

I had the privilege of talking to a big investor in hydrogen fuel a few months ago so my answer will focus on hydrogen as a substitute for fossil fuels rather than the use of hydrogen elsewhere. 1/ Hydrogen cars and trucks exist but they break down a lot and they are not mass produced. There is no infrastructure to repair them either. The investor is funding repair points and fuel points but the route has to be carefully planned to make sure the vehicle arrives to those points 2/ Hydrogen fuel distribution is almost non-existent at the moment (which was the main focus of this investor) and they were looking at building distribution points along the major road networks It's a problem that electric cars don't face as electricity is already everywhere. In the short term, only islands or otherwise very isolated road networks may convert to hydrogen fuel. And that's optimistic.