How does one propose to do that ?
If its a 15KW unit, but more likely a 30kw. it moves a lot of air. & Exhaust, you cant just cover it and direct it out. it has to be vented or blown out with a Fan.
I believe "wuarhat" was referring to the painting of the building post,
... when he said: "Gotta cover up that diesel exhaust", not to cover up the generator.