Hmm, any word on: (1) The hydrogen fuel system itself -- did it burn it? fuel cell? fuel-cell electric hybrid? (2) The fuel and measurement -- A liter of comp

Hmm, any word on: (1) The hydrogen fuel system itself -- did it burn it? fuel cell? fuel-cell electric hybrid? (2) The fuel and measurement -- A liter of compressed* hydrogen doesn't have much energy in it. Are they talking equivalent-gasoline mpg? * And the higher the compression, the heavier the storage tank.