The calorific or heating value is an important indicator of the quality of the pressed fuel briquettes. It measures the energy content of the briquettes. It is defined as the amount of heat evolved when a pressed fuel briquette is completely burnt and the combustion products are cooled. And the Gross Calorific Value, shortened as GCV, refers to the calorific value with the condensation of water in the latent heat, also known as higher heating value. Whereas during combustion, the heat of condensation of water contained in the fuel and formed during combustion will become unavailable because of the vaporization of the water. And then, the useful heating value is gained after the heat of condensation of the water being subtracted from the gross calorific value, which is referred to as the Net Heating Value or lower heating value.
