Comment by ACCount37

9 hours ago

Why?

CNG ICE vehicles exist, especially in parts of the world that have cheap natural gas and expensive gasoline - often as dual fuel retrofits.

They have to deal with high pressure tanks, but compared to the woes of hydrogen storage, that's downright benign.

Good question.

It's just the physical properties of methane.

That's why they use high-pressure tanks because with low-pressure gas storage, the tank needs to be bigger than the car.

Energy density of methane is still lower than any other hydrocarbons.

  • Again: current day CNG ICEs don't actually have "fuel tanks bigger than the car".

    • That's because they use high-pressure tanks.

      Actually higher working presure than regular welders' oxygen tanks.

      Too bad the higher the pressure, the heavier the tank, especially steel.

      I had a pretty good job offer from a company that was going to start building CNG tanks out of carbon fiber.

      This was a few years before the failure of the Titan submersible.

      CNG has made some progress since then, here's the kind of thing there is now:

      https://steelheadcomposites.com/sites/default/files/2024-01/...