Understanding Generator Sizing
Sizing a generator correctly means balancing the connected load, a safety margin, and how the generator will run day to day.
Why a derating factor matters
A generator sized exactly to its expected load leaves no margin for startup surges, future load growth, or less-than-ideal operating conditions. Applying a derating factor builds in that margin.
Load percentage
A generator's load percentage describes how much of its rated capacity is in use at a given time. Running well below or well above the optimal load range can affect efficiency and engine wear.
Estimating fuel consumption
Fuel consumption scales with load: a generator running at a higher load burns fuel faster. Manufacturer spec sheets typically provide a fuel consumption rate per kW that can be used to estimate runtime for a given fuel supply.