"Pipe dream" is not a term I would use to describe the only solution dictated by formal System Engineering analysis of the global energy problem.
If you did any research on what I normally write about, six years and counting 367 stories to date, 8000+ replies like this one, after starting on the global energy problem after coming across it during PhD research, after nearly thirty years systems Engineering, with also historical energy patents I switched to working on this voluntarily because I could see this problem coming.
Do you think I might not know the state of hydrogen technology?
It is routinely transportable. The hardware for all processes are available on alibaba, China is much further ahead with it than you know, like many things now.
If you knew to mathematically sign energy, positive when added to Earth, negative when taken away from Earth, you would quickly realise that any efficiency of a positive energy process is infinitely better than even a 95% efficient negative energy process, because the former is creation, cooling Earth by E=MC squared, whilst the latter is destruction, heating the Earth by 5%, again by E=MC squared.
Any percent of creation, is infinitely better than even 5% destruction.