Is the 'hydrogen economy' still a thing?

IN recent months, there had been a quiet yet nonetheless discernible increase in the volume of interest and discussion about the use of hydrogen as an alternative energy source or to use a broadly encompassing term for it, the "hydrogen economy."

The topic has piqued my interest for a couple of reasons. First and more generally, as a tree-hugging radical greenie, I consider any non-carbon energy concept worth careful study; second and more specifically, hydrogen power was a major area of research and development in my last couple of years with BMW at the beginning of this century. So, I have, perhaps, a slightly better than average understanding of the basic idea and applicable technology.