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The energy content (i.e., calorific value or heating value)
of fuels is also an inherent chemical property. However, calorific
values vary more widely between and within fuel types, as
they are dependent upon the composition of chemical bonds
in the fuel. Given these variations and the relationship between
carbon content and calorific values, carbon content values
for estimating CO2 emissions from
fossil
fuel combustion are expressed in terms of carbon per energy
unit. This form generally provides more accurate emission
estimates than if carbon content factors were expressed in
terms of mass or volume.
Net Calorific Values (NCVs) measure the quantity of heat
liberated by the complete combustion of a unit volume or mass
of a fuel, assuming that the water resulting from combustion
remains as a vapor, and the heat of the vapor is not recovered.
Gross calorific values (GCVs), in contrast, are estimated
assuming that this water vapor is completely condensed and
the heat is recovered, and are therefore slightly larger.
Default data in the Revised 1996 IPCC Guidelines are based on NCVs.
Country-specific net calorific values Appendix
2.1A.3, Table 2.4 of Revised 1996 IPCC Guidelines |
