How much larger (size and weight) is a natural gas generator compared to an equivalent kw output diesel generator? I looked at 500kw gas units and they appeared to be as big or bigger than a 1250kw diesel unit. Or did I just see it that way?
If you look at the energy content of the fuel, that would help with the size.
Gas engines would likely burn cleaner than diesel, and may need less after combustion equipment.
The use of a turbocharger would make any engine look bigger.
Natural gas burns hotter than diesel for a given power output. So a bigger block to deal with more heat. From back in the day I'd have said about 150% the size, but that's been many years now.
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