Discover how generator capacity and load shape fuel…
Diesel generator fuel consumption
by Alex
Expert answer:
Quick answer
Diesel gensets often burn between 0.25 to 1.0 gallons per hour per 5–10 kW load, scaling up with capacity and usage. Charts show consumption at 25%, 50%, 75%, and 100% load.
Detailed answer
Diesel generators vary widely in output—from small 5 kW portables to huge industrial 1,000 kW units. Each has a corresponding fuel consumption chart that outlines gallons per hour (gph) or liters per hour (lph) at different load factors. At 25% load, a genset uses less fuel but also provides limited power. At 100%, it can double or triple consumption.
For example, a 20 kW diesel might burn around 1–2 gallons per hour at half load. Proper sizing ensures you’re not underloading (leading to inefficiency) or overloading (risking damage). Keeping the engine maintained—oil changes, clean filters—helps maintain consistent gph rates. Such data is crucial for budgeting fuel costs and ensuring enough diesel supply during outages or remote operations.