Definition of calorific value

The calorific value provides information on the amount of heat released when a fuel, propellant or combustible is burned without condensation of the water vapor in the exhaust gas occurring.
It indicates how much usable energy can be obtained from each kilogram of the starting material. In a formula, Hi stands for calorific value; its basic unit is J/kg (joules per kilogram).
In fact, it is usually expressed in MJ/kg (megajoules per kilogram), but sometimes the unit kWh/kg (kilowatt hours per kilogram) is also used.
The two units can be easily converted into each other; one kilowatt-hour corresponds to 3.6 megajoules.