When adding data for certain fuel types, you will be asked to select a calorific value. There are two options to choose from:

  • Gross Calorific Value
  • Net Calorific Value


Users should get the calorific value from their invoice/bill or energy supplier, if you cannot find this information select a default value of Gross Calorific Value.



Calorific value represents the amount of heat or energy in a given volume of gas. An average calorific value is calculated monthly by the transporter and allows for any periodic or regional variations in the quality of natural gas.


Gross Calorific Value (GCV) is the amount of heat released by the complete combustion of a unit of natural gas. It is also known as Higher Heating Value (HCV).

Net Calorific Value (NCV) also known as lower heating value (LHV) or lower calorific value (LCV) is determined by subtracting the heat of vaporization of the water vapour from the higher heating value. This treats any H20 formed as a vapor. Natural gas prices are decided on the basis of GCV and NCV.