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To: norwaypinesavage

“To achieve the same energy content as gasoline, a methanol fuel tank needs to be approximately 2.5 times larger. This is due to methanol’s lower energy density compared to gasoline.”

https://www.perplexity.ai/search/gasoline-vs-methanol-how-much-ZLjoysDSSdWZNt.GvPkzwg


20 posted on 08/03/2024 5:47:37 PM PDT by dennisw
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To: dennisw

“To achieve the same energy content as gasoline, a methanol fuel tank needs to be approximately 2.5 times larger. This is due to methanol’s lower energy density compared to gasoline.”

Not entirely accurate, methanol has a 115+ octane rating it can be run without knock on a 16:1 compression.ratio this raises the thermal efficiency of the OTTO cycle 30% to put it in small engines in the 45% BSFC and large ship engines over 50%. The typical petrol ICE is 25 to 30% at best and only in a narrow window of its operating range. With super high octane fuels you can downsize the displacement and go to crazy levels of boost plus every high compression and even higher expansion ratios using VVT and the Miller cycle. You can not do that with petrol it will crater the motor. You also can go to the MCCI cycle which all diesels use and 20:1+ compression ratios here again getting into the 50% BSFC range for large bore engines.

Fuel volumetric density is not the deciding factor. Cost per mile shipped is ships have plenty of volume they are mass limited not volume limited in every case other than maybe iron ore bulk transport or nuclear waste transport. As for vehicles here again going from 25% to 50% BSFC halves the volume difference. Make that a hybrid and halve that again vs a regular petrol ICE. I have driven a regular Corolla vs a hybrid Corolla both 2023 and the hybrid was doubling the urban MPG or better every time.


25 posted on 08/03/2024 7:14:11 PM PDT by GenXPolymath
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