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: 1A3biii - Fuel Combustion Activities - Transport - Road Transportation - Heavy-duty Trucks and Buses
Sector: Transportation : On Road : Heavy-Duty Vehicles

♦ Activity: Fuel combustion - Gasoline

♦ Greenhouse gas: Nitrous oxide ( N2O )

► Year 1990 —

● Greenhouse gas emission estimate —

Amount: 2,292 tonnes of N2O Emitted (710,600 tonnes CO2 Eq.)
Basis: Calculation
Calculation: ([Vehicle miles traveled] * (0.0318 * ([EMFAC NOx emission] / [Vehicle miles traveled]) + 0.0167)) * ([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 = 1,193,893,604 gal of Gasoline
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 = 1,288,560,257 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 NOx emission = 72,644,373,229 g (i.e. 72.64 thousand 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 = 13,639,555,100 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 = 12,637,497,939 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
Parameter: Vehicle miles traveled = 9,815,832,857 mile
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
Constant: Global warming potential of N2O = 310
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: 1.92 g of N2O per gal of Gasoline
595 g of CO2eq. per gal of Gasoline
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