Hydrogen is an energy storage mechanism. When you charge a battery, you get less energy out of the battery than what you put in because of heat loss. But a hydrogen tank can be filled in 5 minutes versus the hours it takes to recharge a battery.
Correct anyone with a freshmen level of thermodynamics who actually paid attention in physics 1301 understands that. Hydrogen is energy storage via chemical means. Using nuclear power to make hydrogen allows you to cut the powerlines and take energy with you. Using solar or wind to make hydrogen allows you to store excess of either for use at a later time or in a location not connected to the energy source. That is the value of hydrogen it is storage on a massive scale if you make the tanks big enough or use the natural gas grid as storage like Germany plans to do. Their gas grid can store 10s of gigawatt hours worth of hydrogen mixed in with the natural gas at up to 20% before it alters the BTU/scf ratio outside pipeline specs.