Comments by "Luredreier" (@Luredreier) on "Hydrogen Powered Liquid Piston Rotary Go-Kart" video.

@paulmichaelfreedman8334 Actually, hydrogen is fairly safe. It's so light that the gas go straight up into the air before it can manage to do much damage. And it's under pressure so it'll be spewing out really really fast in a single direction. You have to collect it somewhere for it to be a problem.
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@paulmichaelfreedman8334 As for usecases. Hydrogen is more energy dense in terms of energy pr kg of weight then a battery. Airplanes are probably a good use case for hydrogen. Also, rural work and military applications may make use of hydrogen, there a hydrogen ICE even makes sense if they're multi-fuel as your can use a solar panel to produce hydrogen from water there and then, yet you also have backup options of fossile fuels, giving you more options. Or you can use hydrogen to get there then refuel with fossile fuel when you get there if you don't have production capability. Likewise in a warzone, you'll use fossil fuels most of the time, but if your unit is cut off you can still produce some hydrogen yourself maintaining some limited combat capabilities even if you can't ship in fuel.
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