Morons. Hydrogen gas in either mined or made from natural gas.
And it takes more energy to produce than it yields when you burn it. This has to be a back door payoff to someone; after millions exchange hands in “R&D” projects, it will never come to pass.
Linde converts natural gas to hydrogen for a living
https://www.lindehydrogen.com/technology/natural-gas-grid-conversion
Or you can use solar/wind/hydro electricity to split water molecules.
What could be greener than that???? / s