3 ms·
Without cryogenics, methane has such low energy density that a low-pressure fuel tank would still have to be as big as a bus for your compact methane-powered ve
by fuzzfactor 7mo ago
Without cryogenics, methane has such low energy density that a low-pressure fuel tank would still have to be as big as a bus for your compact methane-powered vehicle to go as far as you could on a few gallons of gasoline.
- ACCount37 7mo agoWhy? 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.
- fuzzfactor 7mo agoGood 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.
- ACCount37 7mo agoAgain: current day CNG ICEs don't actually have "fuel tanks bigger than the car".
- fuzzfactor 7mo agoThat'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/CNG-Brochure.pdf https://steelheadcomposites.com/sites/default/files/2024-01/...
- ACCount37 7mo agoCOPVs are not exactly a new tech. They're just taking a while to proliferate to those lower end applications. Not like it's a necessary thing. CNG conversions were already viable even with 00s steel tanks.