503K views · Nov 25, 2022 · 16:19 · 2 HN recommenders · 8 mentions · discussed 2022–2023
Engineering Explained examines BMW's Hydrogen 7, a V12 that burns liquid hydrogen or gasoline. He covers cryogenic storage at -253C and why the approach is impractical.
Why Hacker News points people here: Cited in hydrogen threads as a clear explanation of why burning hydrogen in engines is a poor idea.
“Worth watching”HN comment, 2023
“is probably a better person to ask to explain why this is just not going to work”
Explains why hydrogen combustion engines will not work
Maybe, but link is probably a better person to ask to explain why this is just not going to work, through his "The Unfortunate Truth About Toyota's Hydrogen V8 Engine" [1] and "BMW's Hydrogen V12 Engine Is A Hilarious Engineering Stunt" [2] videos. [1] link [2] this video
“Worth watching”
Liquid hydrogen storage problems
If batteries has problems as a long term storage, hydrogen is even worse. If you store liquid hydrogen, you have to let the gas escape or risk explosions. Keeping things below -250ºC is not easy. Worth watching: this video Every single actor is pushing for their own interests and highlighting the flaws of the competitors. You cannot say in good faith that hydrogen, nuclear or fuel are supporting the "renewable energy gang", or that they are not a gang themselves. In fact, my opinions is that nuclear gang was so against renewables that they missed the bus of "renewables + nuclear" friendly mix, letting the gas gang conquest "renewables + gas".
“Liquid hydrogen is an even worse proposition, despite offering greater density than hydrogen gas.”
Explains why liquid hydrogen combustion is a bad proposition
As a great follow-up, Engineering Explained did a video on BMW's hydrogen car that used liquid Hydrogen. this video TL;DW - Liquid hydrogen is an even worse proposition, despite offering greater density than hydrogen gas.
“There are a few issues with that car.”
Issues with BMW's liquid hydrogen car
There are a few issues with that car. this video On the backdrop of the first thing - the part that caught my eye was "Liquid H2 Tank" which... well... yea. That's a different approach than a hydrogen fuel cell.
“goes through many of the engineering and practicality reasons behind that”
Engineering reasons against burning hydrogen in engines
> There's just no logical reason to try and burn hydrogen in ICE engines. In commenting in another spot - this video goes through many of the engineering and practicality reasons behind that.
“neither of them sound very appealing to me”
Engineering Explained covers hydrogen V12 engine
Toyota (in collaboration with Yamaha) is developing a V8 hydrogen combustion engine [1]. BMW is also developing a V12 hydrogen combustion engine [2]. "Engineering Explained" has put out videos on both, and neither of them sound very appealing to me. [3][4] [1] link [2] link [3] link [4] this video
“Nothing more than publicity stunt.”
Yup. BMW made a liquid hydrogen-powered car and the result is...not good. Nothing more than publicity stunt. this video The TL;DW is that since you can't keep it cold enough, eventually the liquid starts to convert to gas, pressure builds up in the tank, and a vent is needed to allow the hydrogen gas to escape. Which then poses a problem, since hydrogen gas is VERY explosive, you can't keep this car in your garage. You have to keep it outside. Then of course there's the issue of this comically large tank taking up the enter back of the car.
“You weren't allowed to park the car in a garage, because it had to vent the hydrogen as it thawed.”
BMW tried that. You weren't allowed to park the car in a garage, because it had to vent the hydrogen as it thawed. this video
