Hydrogen has a carbon footprint. It's just "indirect".
Virtually all hydrogen used the the world today is produced by "reforming" natural gas. "Reforming" is a process where natural gas is burned with limited oxygen and some water thrown in. The chemistry is a bit tricky but hydrogen is produced and CO2 is exhausted.
You can produce hydrogen electrolytic decomposition of water but it results in about a 90% loss of energy. Very expensive proposition and if the electricity was generated with any kind of fossil fuel then that production process generated some carbon.
Only way to use hydrogen without a carbon footprint is to use electrolysis where electricity is generated with something like wind or nuclear.
But I think these new lithium ion batteries that are supposed to come out next year are going to get the job done a lot more efficiently.
All code needs to be maintained. Those offshore guys are quick to grab the money and it doesn't take too long for them to send you the code but it's gotta be maintained otherwise it's garbage. And that's the big problem with off shore development....