Comments by "John Burns" (@johnburns4017) on "Can Hydrogen Fuel the World's Fast-Growing Energy Needs? | WSJ" video.

@PistonAvatarGuy No. For its output a fuel cell is a similar weight and size to an internal combustion engine - and getting smaller.
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Hydrogen is great for large vehicles like: ships, trucks, buses, trains. Cars? Probably not. The hydrogen fuel cells are about 85-90% efficient. Weigh this against an internal combustion engine at around 20% in real world operation. So far more of the hydrogen is converted to propelling a vehicle. This offsets the higher disadvantages of producing hydrogen - it takes more energy to produce hydrogen than energy we get out of it.
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