The reporter on this obviously comes into the piece making a glaring assumption about hydrogen and then does not question basic aspects of the story or show his own independent research. Hydrogen is merely a replacement for batteries, it is an energy storage system, not an energy source. With an efficiency of only 50% going in to the storage tanks it is already far less efficient than batteries. Also, hydrogen atoms are so small that they will tend to pass through the skin of propane tanks so it is likely that those tanks are leaking small amounts of hydrogen regularly, further decreasing efficiency. Far from being an energy bill of zero this man has a huge energy investment, far more than if he had simply used existing technology, batteries, as his energy storage. The reporter, by hanging his story on a sexy "hook" winds up seriously misinforming the reader. I've spent a decade in the renewable energy business and this sort of misleading "news" story does far more harm than good.