Net Heating Value
A heating value is obtained by subtracting the latent heat of vaporization of the water vapor formed by the combustion from the gross or high heating value.
Also known as Lower Heating Value.
Common units used for heating value are:
1 Btu/lb. = 2326.1 J/kg = 0.55556 kcal/kg
1 J/kg = 0.00043 Btu/lb. = 2.39 × 10-4 kcal/kg
1 kcal/kg = 1.80 Btu/lb. = 4187 J/kg