Annex 29 Conversion Factors for Liquid and Gaseous Fuels

Very often, consumption numbers for gasoline and Diesel in transportation or crude oil in the energy sector may be given in liters (L). Further, consumption numbers for gaseous fuels, such as natural gas, may be given in cubic meters (m³). For the Toolkit, these volumes have to be converted into tons or heating values. For the purpose of the Toolkit:

  • 1 L of gasoline has a mass of about 0.74 kg; thus, a conversion factor of 0.00074 must be used to convert liters of gasoline into tons;
  • 1 L of (normal) Diesel fuel (for automobiles, trucks, etc.) and/or light fuel oil (including heating oil) has a mass of about 0.85 kg; thus, a conversion factor of 0.00085 must be used to convert liters of Diesel and/or light fuel oil into tons;
  • 1 L of heavy duty fuel has a mass of about 0.970 kg; thus, a conversion factor of 0.00097 must be used to convert liters of heavy duty fuel into tons;
  • 1 m³ of natural gas has a mass between 0.77 and 0.85 kg; with a mean of 0.8 kg; thus, a conversion factor of 0.0008 must be used to convert m³ of natural gas into tons; a conversion factor of 0.0000008 must be used to convert liters of natural gas into tons;
  • 1 m³ of LPG (mixture of propane and butane) has a mass of about 2 kg; thus, a conversion factor of 0.002 must be used to convert m³ of LPG into tons and a conversion factor of 0.000002 must be applied to convert liters of LPG into tons.

Specific flue gas volume (SFV)

The SFV represents the specific dry flue gas flow of the fuel at reference oxygen. Typical SFV values are:

Coal (O2 ref = 6%) SFV = 350 Nm³/GJ
Fuel oil (O2 ref = 3%) SFV = 280 Nm³/GJ
Natural gas (O2 ref = 3%) SFV = 270 Nm³/GJ
(N: Normal conditions: 0.1013 MPa, 273K)  

These fuel dependent specific flue gas volumes shall be converted for different reference oxygen concentrations, for instance:

Stationary diesel engines with O2 ref = 5% SFV = 315 Nm³/GJ
Stationary gas turbines burning domestic oil with O2 ref = 15% SFV = 840 Nm³/GJ
Stationary gas turbines burning natural gas with O2 ref = 15% SFV = 810 Nm³/GJ

The SFV may also be calculated from the fuel analysis if available. However it should be noted that the SFV depends only slightly on the fuel when expressed in Nm³/GJ.

Calculating emission factors from given concentrations (VGB/EURELECTRIC 2008):

EF = C x SFV / 1,000

where EF: Emission factor (g/GJ)
C: Concentration in the dry flue gas at reference oxygen content (mg/Nm³)