Gross calorific value

The gross calorific value (symbol: Hs) is the energy released during complete combustion when the flue gas is cooled back down to the reference temperature at constant pressure. It therefore additionally contains what is known as the heat of condensation. The gross calorific value is different from the net calorific value. With the net calorific value, the water vapour created during combustion remains in a gaseous form.