Hmm... can't store power from solar or wind ehh? Can't fly a plane or power a tanker with electricity ehh?
Any fuel creation means you're going to incur big losses in creation of it, and then in releasing it, the best you can hope to get out is ~50% efficiency.
Absolute best case combined efficiency of ~35% of going from electricity to a fuel and then into performing work. Realistic would be <20%.
Sounds like, what they actually want is batteries with higher energy density. They can accept charge at >99% and discharge at >99% efficiency.
There are a number of real world possible battery energy storage systems that can provide 5-10x increases in battery energy density. Even better, many of them are capable of stacking upon each other.
If you're going to invest money stolen from the people on a project, batteries is the path that makes sense.