Yeah, we need to generate a lot of green hydrogen anyway, to decarbonise fertilizer, steel production, aviation fuel and a bunch of other stuff (Ideally we'd force fossil fuel producers, the number one users of hydrogen today, to replace their hydrogen with green hydrogen as part of the process of kick starting this).

And in that world, using some of your stored hydrogen or ammonia as emergy reserve makes sense, though you'd want to avoid actually using it too much as if you do then you'd probably have been better spending the money on more generation and/or batteries.