re: “Hydrogen, unlike fossil fuels, doesn’t produce greenhouse gas emissions “
Au contraire!
WV (water vapor) is one of the BIGGEST GHG (green house gases) on the planet!!!!
FYI, the reason they’re not concerned about water vapor as opposed to CO2 is that CO2 takes much longer to get scrubbed from the atmosphere. Water vapor is scrubbed every time it rains.
Top honors for greenhousiest gas goes to sulfur hexafluoride (SF6)