What is the fuel consumption of a 10,000#/hr steam boiler using diesel as fuel (VHI = 130,000 BTU/gal) with a feedwater temperature of 154 °F?
FC = [ SP * ( hs – hw ) / ( BE * VHI ) ]
                            FC = [ SP * ( hs – hw ) / ( BE * VHI ) ]
                            FC = [ 10000 * (1190 – 122) / ( 0.8 * 130000) ]
                            FC = 102.7 gal
Where,
                            FC = Fuel consumption
                            SP = steam produced
                            hs = enthalpy of steam @ 100 PSIG
                            hw = enthalpy of feedwater @ saturation temperature
                            BE = Boiler efficiency
                            VHI = Fuel heating value

NOTES - The following will help in the use of this formula
                            hs = 1190 BTU/# constant @ 100 PSIG
                            hw = enthalpy of saturated water at saturation temperature (steam tables)
                            Boiler efficiency is assumed to be 80%
                            Common fuel heating values: