Nitrogen Emissions from U.S. Transportation Sources John Davies - PowerPoint PPT Presentation

Nitrogen Emissions from U.S. Transportation Sources John Davies Office of Transportation and Air Quality U.S. EPA April. 9, 2008

Overview „ Transportation Combustion emissions … NO x … N 2 O … Relative significance of activity trends and emissions controls „ Factors affecting transportation fuel consumption and GHG emissions „ Relationship of NOx / N2O emissions controls to fuel consumption

U.S. NO X Emissions in 2005 Industrial processes, waste disposal & other 7% On-Road Vehicles 43% Stationary Fuel Combustion 38% Nonroad Vehicles 12% Source: Inventory of U.S. Greenhouse Gas Emissions and Sinks, 1990-2005

U.S. N 2 O Emissions in 2005 Other Sources 14% On-Road Vehicles Agricultural and Soil 7% Management 78% Non-Road Mobile 0.8% Source: Inventory of U.S. Greenhouse Gas Emissions and Sinks, 1990-2005

Greenhouse Gas Emissions by Gas, 2005 HFCs, PFCs N 2 O N 2 O HFCs HFCs HFCs HFCs & SF 6 N 2 O N 2 O 1. 1. 7% 7% 3. 3. 0% 0% 3.3% 1.9% CH 4 CH 4 2.2% 2.2% 6.5% 6.5% 0.1% 0.1% CH 4 CH 4 7.4% 7.4% CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 95.1% 95.1% 83.8% 83.8% 94.7.% 85% 85% 95.1% 95.1% Transportation Only Transportation Only All U.S. Sources All U.S. Sources Source: Inventory of U.S. Greenhouse Gas Emissions and Sinks, 1990-2005

Change in U.S. Vehicle Movement, 1990-2005 Population +19% GDP +55% Light-Duty Vehicle Miles Traveled +39% Vehicles Freight Ton-Miles +58% Trucks Commercial Passenger Miles Traveled +68.8% Aircraft 0% 10% 20% 30% 40% 50% 60% 70% Sources: Highway Statistics 2006 Table VM-1, National Transportation Statistics 2005 Table 4-21

Change in U.S. Vehicle Movement, 1990-2005 Population +19% GDP +55% Light-Duty Vehicle Miles Traveled +39% Vehicles Freight Ton-Miles +58% Trucks Commercial Passenger Miles Traveled +68.8% Aircraft -37.6% On-Road + Air NOx -18.3% Road + Air N20 0% 10% 20% 30% 40% 50% 60% 70% Sources: Highway Statistics 2006 Table VM-1, National Transportation Statistics 2005 Table 4-21 Inventory of U.S. GHG Emissions and Sinks

Factors Affecting Mobile N 2 O and NO X tailpipe emissions „ Vehicle activity „ Fuel consumption „ Fuel characteristics „ Air-Fuel mixes „ Combustion temperatures „ Emissions control equipment

Change in U.S. Vehicle Movement, 1990-2005 Light-Duty Vehicle Miles Traveled +39% Vehicles -47% NOx -20.5% N2O Freight Ton-Miles +58% Trucks -24% NOx N2O +35.2% Commercial Passenger Miles Traveled +68.8% Aircraft NOx +62% N2O +1% 0% 10% 20% 30% 40% 50% 60% 70% Sources: Highway Statistics 2006 Table VM-1, National Transportation Statistics 2005 Table 4-21

NO x Trends U.S. NOx Emissions, 1970 - 2006 Millions of short tons 30.00 25.00 20.00 Other 15.00 Stationary Fuel Combustion 10.00 Nonroad Vehicles 5.00 On-Road Vehicles 0.00 1 970 1 975 1 980 1 985 1 990 1 995 2000 2001 2002 2003 2004 2005 2006 EPA Tier O – B egan e arl y EPA Tier 1 – 1990 Oxidation Catalyst EPA Tier 2 - 2004 1980s; common until 1984 1975 to 1980 (cars) Added advanced emissions Added more advanced and 1980 to 1985 Implemented in cars and LD controls, including elec. emissions controls, including (trucks) trucks Controlled fuel injection & improved combustion, ignition timing, EGR and air 3-way catalyst; on-board injection NOx reduced 90 percent from diagnostic computer and oxygen Tier 0 sensor NOx reduced 60 percent from Tier 0 Nonroad Diesel Reduced NOX to nitrogen and Diesel truck Rule oxygen; 1.0 g / mil for cars and bus Locomotive and standards Marine Rule

N 2 O Trends 600 500 Other 400 300 Agricultural and Soil 200 Management 100 Nonoad Mobile On-Road Vehicles 0 1990 1995 2000 2001 2002 2003 2004 2005 Source: Inventory of U.S. Greenhouse Gas Emissions and Sinks, 1990-2005

Factors Affecting Mobile N2O and NOX tailpipe emissions „ Fuel characteristics „ Air-Fuel mixes „ Combustion temperatures „ Use of pollution control equipment „ N2O in particular can be formed by catalytic processes used to control NOx, CO, and hydrocarbon emissions

Impact of Emissions Control Devices on Transportation N2O Emissions Transportation GHG Emissions by Gas (Indexed to 1990) 1.4 1.2 CO 2 1 0.8 N 2 O 0.6 0.4 CH 4 0.2 0 1990 1992 1994 1996 1998 2000 2002 2004 2006 1975 1980 Oxidation EPA Tier O – EPA Tier 1 EPA Tier 2 – 2004 Catalyst 1975 Increased per-mile Reduced N2O emissions by Reduced N2O emissions to 1980 (cars) N2O through NOx rates, but still higher than 90 percent relative to Tier 1 and 1980 to controls non-catalyst systems 1985 (trucks) Increased N2O Rate = 0.0036 g / mi emissions rate Rate = Rate = almost 3X 0.064 g / mi 0.0429 g / mi Rate = 0.050 g / mile Source: Inventory of U.S. Greenhouse Gas Emissions and Sinks, 1990-2005

Transportation Source GHGs Relative to Total U.S. Emissions Share of Mobile Emissions U.S. Greenhouse Gas Emissions, Transportation (Tg CO 2 Eq.) 2005 Sector GHGs Lubricants 10.2 0.5% Other Non-Road 176.2 8.7% 7.9% Commercial Aircraft 158.1 0.7% Refrigerated Transport 13.6 Freight Trucks Transportation 19.1% 385.8 28% Buses and Motorcycles 17.1 0.8% (2014.0 Tg CO 2 Eq) Mobile Air Condition ing 53.1 2.6% Light-Duty Trucks Other Sectors 566.7 72% 59.5% (5246.7 Tg CO 2 Eq) Passenger Cars 632.9 N/A Included primarily in Non-Transportation Mob le Sources i Industrial sector estimates 191.8 Reported in Inventory, but not included International Bunkers - Air and Marine Source: Inventory of U.S. Greenhouse N/A in U.S. Total GHG Estimate or 95.6 (Official Estimate) Gas Emiss ons and Sinks, 1990-2005 i Transportation Sector Estimate

U.S. Greenhouse Gas Emissions, 1990-2005, Transportation and other U.S. Sources 8000 7260.4 7000 6242.0 6000 5000 Other U.S. Sources 4000 3000 191.8 Non-Transportation 129.1 2000 Mobile 2014.2 1987.1 1934.7 1932.5 1906.7 1879.8 1852.2 1785.2 1723.0 1750.4 1680.3 1645.2 1592.6 1539.4 1526.1 1496.0 Transportation 1000 0 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 Absolute increase, 1990-2005 Percent Change, 1990-2005 Transportation + 487.9 Tg CO 2 Eq. Transportation +32.0% Non-Trans Mobile +62.7 Tg Co2 Eq. Non-Trans Mobile +48.6% All other sources + 467.8 Tg CO 2 Eq. All other sources + 10.2% Total +1018.4 Tg CO 2 Eq. Total (including transport) +16.3% Source: Inventory of U.S. Greenhouse Gas Emissions and Sinks, 1990-2005

Impact of U.S. Fuel Consumption since 1990 US CO 2 Emissions from Fossil Fuel Combustion 6000 5000 Other U.S. Sources 4000 3000 Non-Transportation 2000 Mobile Transportation 1000 0 1990 1995 2000 2001 2002 2003 2004 2005 Absolute increase, 1990-2005 Percent Change, 1990-2005 Transportation + 431.9 Tg Transportation +29.4% Non-Trans Mobile + 62.1 Tg Non-Trans Mobile +48.6% All other sources + 534.1 Tg All other sources + 11.2% Total +1027.1 Tg Total (including transport) +21.7%

Per Capita CO2 Emissions from Fossil Fuel Combustion, 1990 and 2005 1,130 lbs 12,956 lbs 27,634 lbs 1990 41,720lbs Non-Trans Transportation Other U.S. Sectors Mobile 1,412.7 lbs 42,762 lbs 14,112 lbs 2005 27,237 lbs 0 10000 20000 30000 40000 50000 Sources: Inventory of U.S. Greenhouse Gas Emissions and Sinks, 1990-2005 U.S. Census Bureau, Population Division

U.S. GHG Emissions by Gas - All Sources 1990 and 2005 6089.5 6000 1990 5061.6 2005 5000 4000 3000 2000 1000 609.1 539.3 482.0 468.6 163.0 89.3 0 CO2 CH4 N2O HFCs. PFCs and SF6

U.S. Transportation GHG Emissions by Gas, 1990 and 2005 6000 1990 2005 5000 4000 3000 1908.1 2000 1478.8 1000 42.7 36.5 4.5 2.3 N/A 67.1 0 CO2 CH4 N2O HFCs. (Reflects the phase-in HFCs for ozone- deleting substances)

US Transportation GHGs by Major Source, 1990 and 2005 1 1 99.6 1200 1990 2005 972.6 1000 23.3% 800 600 385.8 400 270.5 227.7 1 88.1 1 58.1 69.4% 200 1 37.7 14.8% 0 Other * Light-Duty Freight Trucks Commercial Vehicles Aricraft *Other GHGs include emissions from HFCs, which were introduced beginning in the early 1990s to replace ozone depleting substances; increase from 1990 is not meaningful. Source: Inventory of U.S. Greenhouse Gas Emissions and Sinks, 1990-2005

Change in Vehicle Movement, 1990-2005 Light-Duty Vehicle Miles Traveled +39% Vehicles Freight Vehicle Miles +52% Trucks Commercial Passenger Miles Traveled +68.8% Aircraft 0% 10% 20% 30% 40% 50% 60% 70% Sources: Highway Statistics 2006 Table VM-1, National Transportation Statistics 2005 Table 4-21

Change in Activity, Intensity and GHGs, 1990-2005 (Passenger Miles and Ton-Miles) Passenger Miles Traveled +37% Light-Duty Vehicles -10.2% GHGs +23.3% GHGs / PMT GHGs / ton-mile Ton-Miles +58% +7.3% Freight Trucks GHGs +69.4% Passenger Miles Traveled +68.8% Commercial Aircraft -32.0% GHGs +14.8% GHGs / PMT 0% 10% 20% 30% 40% 50% 60% 70% Sources: Highway Statistics 2006 Table VM-1, National Transportation Statistics 2005 Table 4-21