Manufacturer-documented fuel consumption for 13 40–45 kW Natural Gas generator sets — median 121.52 gal/h at full load, 13.39 gal/h at half load.
Compare 40–45 kW Natural Gas generator specs side-by-side →
| Model | kW | gal/h @ 50% | gal/h @ 100% | Tank (L) | Runtime @ 50% (h) |
|---|---|---|---|---|---|
| Generac 3.9GN | 40 | 69.74 | 133.14 | — | — |
| Katolight 40FDG4 | 40 | — | 121.52 | — | — |
| Katolight 40FGG4 | 40 | — | 121.52 | — | — |
| Katolight 40FJG4 | 40 | — | 121.52 | — | — |
| Katolight 40FNG4 | 40 | — | 121.52 | — | — |
| Katolight 40FPG4 | 40 | — | 121.52 | — | — |
| Katolight 40FRG4 | 40 | — | 121.52 | — | — |
| Kohler KG40 | 40 | 28.32 | 46.28 | — | — |
| MTU 4R0063 GS40 | 40 | 1.37 | 2.62 | — | — |
| Wildcat Roughneck NG 40KW | 40 | — | 4.50 | — | — |
| Cummins/Onan 42GGFE | 42 | 3.59 | 6.00 | — | — |
| Kohler 35RZ | 42 | 23.19 | 40.39 | — | — |
| Kohler 45ERES | 44 | 2.54 | 4.57 | — | — |
Figures from each model’s own manufacturer documentation (spec sheets and manuals); runtime = documented tank capacity ÷ consumption at 50% load. Verify against the datasheet for your exact configuration.
Across 13 models with manufacturer data, full-load consumption runs 2.62–133.14 gal/h (median 121.52); at 50% load the median is 13.39 gal/h.