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Boiler Fuel & Efficiency Calculators
Use the left calculator for estimated hourly fuel consumption and the right calculator for boiler efficiency based on real operating data. Pressure is entered as barg and internally converted to absolute pressure. Feed water and steam enthalpy values are interpolated from thermodynamic tables.
Fuel Consumption Calculator
Estimated
kg/h
barg
0.0 barg
°C
40 °C
%
Estimated Fuel Consumption
—
Enter values
Heat Required Per kg Steam
—
kcal/kg
Steam Enthalpy, hg
—
Feed Water Enthalpy, hf
—
Absolute Pressure
—
Selected Fuel NCV
—
Boiler Efficiency Calculator
Linked + Direct
kg/h
barg
0.0 barg
°C
40 °C
—
Boiler Efficiency
—
NCV basis
Effective System Efficiency
—
Reference feed water: 20°C
Steam Enthalpy, hg
—
Feed Water Enthalpy, hf
—
Fuel Input Energy
—
Net Steam Energy
—
Important Note:
There are two ways to read the result. Boiler Efficiency is the classic direct-method value based on the actual feed water temperature and the real or linked fuel consumption. Effective System Efficiency shows the plant-level benefit of hotter feed water by comparing steam output against a fixed 20°C reference feed water. In linked mode, feed water temperature rises will reduce estimated fuel consumption.
Boiler Efficiency = [Steam Capacity × (hg − hf_actual)] / [Fuel Consumption × NCV] × 100
Effective System Efficiency = [Steam Capacity × (hg − hf_at_20°C)] / [Fuel Consumption × NCV] × 100
