Fuel Calorific Values

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

Higher Calorific Value (or Gross Calorific Value – GCV, or Higher Heating Value – HHV) – the water of combustion is entirely condensed and that the heat contained in the water vapor is recovered;
Lower Calorific Value (or Net Calorific Value – NCV, or Lower Heating Value – LHV) – the products of combustion contains the water vapor and that the heat in the water vapor is not recovered.

Natural gas	12500 kcal/kg
Propane-butane	11950 kcal/kg
Disel	10000 kcal/kg
Fuel oil	9520 kcal/kg
Brown coal	3500 kcal/kg
Woods	2500 kcal/kg
Electricity	860 kcal/kWh