Interesting fuel figures.
Got a Scangauge D and programmed it, a very cool tool!
Per Onan, the 4kw Onan uses about .5gph at 1/2 load.
Per SGD, the 5.9 Cummins uses .3gph when warm at idle in N.
One AC on, .4gph.
2 ACs on, .5gph.
No AC at idle in D, .5gph.