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Improving Air Quality: Controlling Mobile Sources Chapter 11.

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Presentation on theme: "Improving Air Quality: Controlling Mobile Sources Chapter 11."— Presentation transcript:

1 Improving Air Quality: Controlling Mobile Sources Chapter 11

2 1. Understanding Urban Air Problems Measuring Urban Air Quality EPA monitors the air in relatively large metropolitan statistical areas (MSAs) and reports part of its findings using the ____________________ (AQI) AQI is reported as the highest of five pollutant- specific index values (ranging between 0 & 500) for that day and signifies the worst daily air quality in an urban area over a given time period – five of the criteria pollutants: PM, SO 2, CO, O 3, & NO 2 – An AQI of 100 is considered to correspond to the standard set by CAA 2

3 Photochemical Smog in Urban Areas Formed from pollutants that chemically react in sunlight to form new substances Principal component is tropospheric (ground- level) ozone (O 3 ) – Formed from a chemical reaction of ___ and volatile organic compounds ( _____ ) and sunlight – Released by stationary and mobile sources – Highest emitters of smog precursors among transportation sources are _________________ 3

4 2. Controlling Mobile Sources 1990 Clean Air Act Amendments 1990 Clean Air Act Amendments strengthened U.S. controls on motor vehicle emissions and fuels through _______ Includes tougher emissions requirements, fuel quality controls, and incentives to encourage development of cleaner-running vehicles and cleaner alternative fuels 4

5 Tier I Phased in between 1994 and 1998 Aimed at reducing emissions of non-methane hydrocarbons (NMHC), carbon monoxide (CO), nitrogen oxides (NOx), and particulate matter (PM) Passenger cars and light trucks subject to tighter regulation than heavier SUVs, minivans, pickup trucks Stricter controls for initial 5 years or 50,000 miles of use; less stringent controls for remainder of vehicle’s useful life redefined as 10 years or 100,000 miles 5 (1) Emissions Reductions The policy focuses on the manufacture of these vehicles standards on tailpipe emissions

6 Tier II Phased in between 2004 and 2008 Tougher requirements given for each successive model year Unique to this tier of controls is: – an interrelated system of controls on vehicles and fuels – no distinction for vehicle size 6 further reductions in pollutant releases

7 (2) Fuel Quality Controls Prohibits leaded fuel after 1995 Requires ____________________ in certain ozone nonattainment areas – Fuels that emit less hydrocarbons, carbon monoxide, and toxics than conventional gasoline Requires __________________ in certain CO nonattainment areas – Formulations with enhanced oxygen content to allow for more complete combustion and hence a reduction in CO emissions 7

8 (3) Clean Fuel Vehicles 1990 amendments established a ___________ _____________________ – A clean fuel vehicle is certified to meet stringent emission standards for such pollutants as CO, NO X, PM, and formaldehyde In ozone and CO nonattainment areas, a proportion of new fleet vehicles had to be clean fuel vehicles and had to use clean alternative fuels ( _____________________________ …) 8

9 3. Economic Analysis of Mobile Source Controls Policy Characteristics to Analyze absence of benefit-cost analysis in setting emissions standards uniformity of auto emissions standards inherent bias against new vehicles implications of clean fuel alternatives 9

10 (1) Absence of Benefit-Cost Analysis: An Inefficient Decision Rule New standards were _________________, i.e., set specifically to compel auto industry to find solutions – Perversely gave manufacturers a strong case to seek adjustments and postponements for compliance New standards were ________________ – Set solely to protect public health and welfare – Implies the standards were set to _________ _____, where MSB = 0 versus to achieve efficiency, where MSB = MSC 10

11 Benefit-Based Emission Standards $ Abatement MSB MSC AEAE A 0 where MSB = 0 0 Benefit-based standards imply abatement at A 0 which is higher than A E. Suggests _____________ of mobile sources. 11

12 (2) Uniformity of Auto Emissions Standards With few exceptions, emission standards are applicable on every model produced with no regard to where the vehicle will be driven – This ________________ “clean” areas and ______________ “dirty” areas because MSB in more polluted regions should be higher than in cleaner regions, making the efficient abatement level higher in dirtier regions Studies suggest there would be considerable cost savings if a two-tiered standard replaced the uniform standard 12

13 Two-tiered Standard 13 $ MSC MSB dirty MSB clean Abatement A STclean A STdirty 0 One study shows a $23B savings over 10 years

14 (3) Bias Against New Vehicles More stringent controls on new vehicles bias consumer decisions against new cars (regulations on new cars add to costs which elevates relative price) As P NewCars , D UsedCars __ (substitutes), which perversely encourages use of higher-emitting cars 14

15 Bias Against New Vehicles 15 $ QQ D1D1 S1S1 S2S2 D1D1 D2D2 S1S1 Q1Q1 Q2Q2 Q1Q1 Q2Q2 P2P2 P1P1 P1P1 P2P2 New Cars Used Cars

16 (4) Implications of Clean Fuel Alternatives Advanced fuels are required only in the dirtier regions of the country Since this aligns higher MSC of developing and using new fuels with higher MSB of cleaning up in dirtier regions, it may approach an efficient solution 16

17 Smog http://en.wikipedia.org/wiki/Smog http://en.wikipedia.org/wiki/Smog Smog is a kind of air pollution; the word "smog" is a portmanteau of smoke and fog. Classic smog results from large amounts of coal burning in an area caused by a mixture of smoke and sulfur dioxide. Modern smog does not usually come from coal but from vehicular and industrial emissions that are acted on in the atmosphere by sunlight to form secondary pollutants that also combine with the primary emissions to form photochemical smog.air pollutionportmanteausmokefogsulfur dioxidephotochemical smog 17

18 Smog A photochemical smog is the chemical reaction of sunlight, nitrogen oxides (NO x ) and volatile organic compounds (VOCs) in the atmosphere, which leaves airborne particles (called particulate matter) and ground-level ozone.nitrogen oxidesvolatile organic compoundsparticulate matterozone Nitrogen oxides are released by nitrogen and oxygen in the air reacting together under high temperature such as in the exhaust of fossil fuel-burning engines in cars, trucks, coal power plants, and industrial manufacturing factories. VOCs are released from man-made sources such as gasoline (petrol), paints, solvents, pesticides, and biogenic sources, such as pine and citrus tree emissions.fossil fuelcarscoalpower plantsgasolinepaints solventspesticides 18

19 Smog ground-level ozone sulfur dioxide nitrogen oxides (such as nitrogen dioxide) nitrogen oxidesnitrogen dioxide carbon monoxide volatile organic compounds (VOCs) volatile organic compounds peroxyacyl nitrates (PAN) peroxyacyl nitrates aldehydes (R'O) aldehydes 19

20 Smog Characteristic coloration for smog in California in the beige cloud bank behind Golden Gate Bridge. The brown coloration is due to the NOx in the photochemical smog.CaliforniaGolden Gate Bridge 20


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