Last reviewed on November 2, 2011 at 10:05

Documentation of California's Greenhouse Gas Inventory (First Edition - Last updated on 11/19/2007)

♦ Category: Energy

IPCC: 1A3bi - Fuel Combustion Activities - Transport - Road Transportation - Cars
Sector: Transportation : On Road : Passenger Cars

♦ Activity: Fuel combustion - Distillate

♦ Greenhouse gas: Methane ( CH4 )

► Year 1990 —

● Greenhouse gas emission estimate —

Amount: 27.44 tonnes of CH4 Emitted (576.30 tonnes CO2 Eq.)
Basis: Calculation
Calculation: [EMFAC CH4 emission] * ([FHWA fuel sales] / [EMFAC total fuel combustion])
Reference: ARB (2009). Technical Support Document for California’s Greenhouse Gas Emissions Inventory and 1990 Emissions Level. California Air Resources Board. (March 2009). Available online at: /cc/inventory/doc/methods_v1/ghg_inventory_technical_support_document.pdf

● Activity level used in calculations —

Activity: Fuel combustion = 60,113,398 gal of Distillate
Basis: Calculation
Calculation: [EMFAC category fuel combustion] * ([FHWA fuel sales] / [EMFAC total fuel combustion])
Reference: ARB (2009). Technical Support Document for California’s Greenhouse Gas Emissions Inventory and 1990 Emissions Level. California Air Resources Board. (March 2009). Available online at: /cc/inventory/doc/methods_v1/ghg_inventory_technical_support_document.pdf

● Parameters and Constants used in calculations —

Parameter: EMFAC category fuel combustion = 71,285,712 gal
Reference: ARB (2007). The California Air Resources Board's EMission FACtors (EMFAC) model was used to calculate emission rates from all motor vehicles, such as passenger cars to heavy-duty trucks, operating on highways, freeways and local roads in California. Model and documentation available online at: /msei/onroad/latest_version.htm
Parameter: EMFAC CH4 emission = 32,543,228 g (i.e. 32.54 tonnes)
Reference: ARB (2007). The California Air Resources Board's EMission FACtors (EMFAC) model was used to calculate emission rates from all motor vehicles, such as passenger cars to heavy-duty trucks, operating on highways, freeways and local roads in California. Model and documentation available online at: /msei/onroad/latest_version.htm
Parameter: EMFAC total fuel combustion = 2,157,919,828 gal
Reference: ARB (2007). The California Air Resources Board's EMission FACtors (EMFAC) model was used to calculate emission rates from all motor vehicles, such as passenger cars to heavy-duty trucks, operating on highways, freeways and local roads in California. Model and documentation available online at: /msei/onroad/latest_version.htm
Parameter: FHWA fuel sales = 1,819,718,000 gal
Reference: FHWA (various). US Department of Transportation, Federal Highway Administration - Highway Statistics (volumes 1990 - 2005). Note: FHWA classifies diesel (a.k.a. distillate) fuel as 'special fuels'. Data available online at: http://www.fhwa.dot.gov/policy/ohpi/hss/hsspubs.cfm
Constant: Global warming potential of CH4 = 21
Reference: IPCC (1996). Second Assessment Report. Climate Change 1995: WG I - The Science of Climate Change. Intergovernmental Panel on Climate Change; J.T. Houghton, L.G. Meira Filho, B.A. Callander, N. Harris, A. Kattenberg, and K. Maskell (eds.); Cambridge University Press. Cambridge, U.K.

● Greenhouse gas emitted per unit activity —

Amount: 0.457 g of CH4 per gal of Distillate
9.59 g of CO2eq. per gal of Distillate
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