3 HN users recommended this explainer4 months2022–2024score 4.5
Years with an HN recommendation, 2007–2026
HN uses it as the go-to explanation of why hydrogen internal combustion engines do not make sense.
Engineering Explained examines Toyota's hydrogen-burning V8 engine built with Yamaha and explains the practical problems of hydrogen combustion vehicles. It covers efficiency, storage and distribution issues.
“Here's a very factual explanation of why hydrogen internal combustion engines won't work” (HN, 2023)
The YouTube channel Engineering Explained has an excellent video regarding why hydrogen is not a practical replacement for gasoline/petrol/diesel in a traditional internal combustion engine: [this video]
Why hydrogen is not a practical fuel for combustion engines.
YouTube's Engineering Explained channel took a close look at the hydrogen engine Toyota recently unveiled and in doing so explained a lot of problems you can expect with hydrogen engines - including distribution and storage issues. Watch here: [this video]
Explains problems with hydrogen engines, including distribution and storage.
WRT hydrogen engines: This video explains why using hydrogen to power an internal combustion engine doesn't make sense: [this video] Lots of more informative responses in this thread than I can explain; just remember that a lot of people are promoting "hydrogen" in situations where it is either economically inferior to traditional batteries, or where the laws of physics make it impractical. (IE, the hydrogen V8 requires tanks so large that the vehicle is impractical.) In whatever hydrogen space you're getting into, make sure you run the numbers like this video does. (IE, efficiency, volume of compressed hydrogen, energy lost to compressing / refrigerating, ect,) and make sure they make sense. For example, hydrogen might not make sense for day-to-day storage compared to a battery, but it may make perfect sense for a replacement for a standby generator.
Why hydrogen in an internal combustion engine doesn't make sense.
> collect facts The physical properties and limitations of hydrogen are well-known. Many people repeat them in other posts in this thread. Here's a very factual explanation of why hydrogen internal combustion engines won't work: [this video] (In summary, you can't compress hydrogen enough to fit in a reasonably-sized tank. The energy that it takes to compress hydrogen will be expensive.)
Factual explanation of why hydrogen combustion engines won't work.
Except containing hydrogen requires bulky tanks. I was curious, and googled.. It turns out the only hydrogen car I'm aware of that's on sale in the US (Toyota Mirai) weighs several hundred pounds more than the most popular EV in the US (Tesla Model 3).. ~4300lbs vs ~3900lbs. Except the Mirai isn't a pure hydrogen car.. its more of an EV with a hydrogen powered generator. I'm not aware of any purely hydrogen fueled cars on sale. i watched a fascinating YT video by Engineering Explained that went into the reasons why a pure hydrogen car is not practical ( [this video] )
Fuel cells in the vehicle would be much more efficient. Combustion generators in the car have storage issues and efficiency issues. liquid hydrogen needs cryogenic storage, compressed hydrogen isn't space efficient relative to the output. Combustion generators at home would suffer from the same storage problems as in cars. [this video]
Hydrogen combustion engines face storage and efficiency problems.
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] [this video] [2] [link]
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] [this video] [4] [link]
Critical look at Toyota and BMW hydrogen combustion engines.
Hydrogen fuel cells can be made to work, they're currently somewhat worse than lithium-ion batteries in terms of energy storage but it's not completely hopeless. On the other hand, hydrogen combustion is an inefficient process that uses an astonishingly bulky, expensive fuel that needs to be compressed to absurd pressures and has no realistic use case - except to give petrolheads hope that things don't have to change and to kick the can down the road while continuing to burn fossil fuels. Check out this analysis: [this video] or the numerous sources cited. This is not about German car companies like BMW, Volkswagen, and Mercedes being cut off from productive lines of inquiry. Those lines were only undertaken for show to allow them to continue business as usual. This is about them successfully bribing the German government to allow them to keep destroying the planet.
Analysis of why hydrogen combustion is impractical.
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