This has been hashed out several times. Hydrogen is a net energy loser, has poor volumetric energy density, metal embrittlement is a serious problem. If the German government wants to virtue signal by subsidizing research and production, let them waste their money. In the long run it will so them no good. There are only two ways to produce hydrogen - either cracking water through electrolysis or cracking natural gas. In both processes the energy required to make the hydrogen greatly exceeds the amount you get from burning it as a transportation fuel. And that IS including catalysts to aid in cracking the chemical bonds in both substances.
It does not pay off economically and never will.
