Research team develops 2-liter class hydrogen engine capable of running entirely on hydrogen

https://techxplore.com/news/2023-09-team-liter-class-hydrogen-capable.html

"irect injection hydrogen engine... pressure >30 bar... turbo charger maintains high thermal efficiency in all domains from ignition to engine load's upper limit allowing stable operation... resolved issue of backfire by injecting high-pressure hydrogen fuel directly into combustion chamber... reduce carbon dioxide and fine dust emissions by 99 and 90% respectively meeting EU's zero-emission requirements... emits nitrogen oxides <15 ppm even without after treatment system purifying exhaust gases... thermal efficiency 40%"

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