Fuel Calorific Value

The calorific value of a fuel
The calorific value of a fuel is the quantity of heat produced by its combustion – at constant pressure and under “normal” conditions (i.e. to 0oC and under a pressure of 1,013 mbar).

The combustion process generates water vapor and certain techniques may be used to recover the quantity of heat contained in this water vapor by condensing it.
The Higher Calorific Value (or Gross Calorific Value – GCV) suppose that the water of combustion is entirely condensed and that the heat contained in the water vapor is recovered.

The Lower Calorific Value (or Net Calorific Value – NCV) suppose that the products of combustion contains the water vapor and that the heat in the water vapor is not recovered.

Fuel	Higher Calorific Value (Gross Calorific Value – GCV)
kJ/kg	Btu/lb
Acetone	29,000
Alcohol, 96%	30,000
Anthracite	32,500 – 34,000	14,000 – 14,500
Bituminous coal	17,000 – 23,250	7,300 – 10,000
Butane	49,510	20,900
Carbon	34,080
Charcoal	29,600	12,800
Coal	15,000 – 27,000	8,000 – 14,000
Coke	28,000 – 31,000	12,000 – 13,500
Diesel	44,800	19,300
Ethanol	29,700	12,800
Ether	43,000
Gasoline	47,300	20,400
Glycerin	19,000
Hydrogen	141,790	61,000
Lignite	16,300	7,000
Methane	55,530
Oils, vegetable	39,000 – 48,000
Peat	13,800 – 20,500	5,500 – 8,800
Petrol	48,000
Petroleum	43,000
Propane	50,350
Semi anthracite	26,700 – 32,500	11,500 – 14,000
Sulfur	9,200
Tar	36,000
Turpentine	44,000
Wood (dry)	14,400 – 17,400	6,200 – 7,500
	kJ/m3	Btu/ft3
Acetylene	56,000
Butane C4H10	133,000
Hydrogen	13,000
Natural gas	43,000
Methane CH4	39,820
Propane C3H8	101,000
Town gas	18,000
	kJ/l	Btu/gal
Gas oil	38,000	164,000
Heavy fuel oil	41,200	177,000
Kerosene	35,000	154,000

• 1 kJ/kg = 0.4299 Btu/ lbm = 0.23884 kcal/kg
• 1 Btu/lbm = 2.326 kJ/kg = 1.8 kcal/kg