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  • Lecture for ECE 2004, first day on air pollution. Gives an overview of the problem
  • Lecture for ECE 2004, first day on air pollution. Gives an overview of the problem
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • What Does A Catalytic Converter Do?  In an effort to control automotive emissions, reduce carbon monoxide, smog, and acid rain catalytic converters began appearing on cars in the 1970's. Over the decades, automotive manufacturers have used many methods to control exhaust emissions. Exhaust gas re-circulation, containment systems for evaporative emission, on board engine management systems, air pumps, are just some examples of their efforts, but the single most effective way to reduce exhaust emissions has been the catalytic converter. The catalytic converter has evolved over from the decades to where most modern vehicles are equipped with a three-way converter that effectively reduces harmful exhaust gases. The catalytic converter usually looks like a muffler and is located underneath the vehicle in the proximity of the passenger seat in most cars although some cars have multiple converters. The purpose of a catalytic converter is to convert harmful hydrocarbons, carbon monoxide, and nitrogen oxides into harmless compounds. The catalysts inside the catalytic converter convert carbon monoxide and hydrocarbons into carbon dioxide and water, and nitrogen oxides back into nitrogen and oxygen.     The catalysts inside of the catalytic converter are precious metals such as platinum, palladium, and rhodium coated on a ceramic honeycomb structure or pellets. When exhaust contacts the catalysts a chemical reaction takes place converting the harmful exhaust gases into harmless compounds. Most modern converters contain two distinct catalysts, the reduction catalyst and the oxidation catalyst.  The first stage, or reduction catalyst, consists of a ceramic honeycomb coated with platinum and rhodium. In this section of the converter, Nox emissions are converted to oxygen and nitrogen. The exhaust then flows to the second stage, or oxidation catalyst. It is here where unburned hydrocarbons and carbon monoxide are burned or oxidized by passing them over a platinum and palladium honeycomb. The oxygen from the first stage further aids this oxidizing.  The third stage of controlling emissions utilizes an engine management system. Although every automotive manufacturer employs different methods and components, most utilize an oxygen sensor mounted upstream of the converter which transmits a voltage to an onboard computer. This voltage reading varies with the amount of oxygen present in the exhaust gas. The ideal air fuel ratio for gasoline is 14.7 to 1. If the ratio of air is less than 14.7, then there will be fuel present in the exhaust after combustion therefore creating a rich condition. A lean condition occurs when the ratio of air to fuel exceeds 14.7 to 1. The engine management system uses the voltage reading from the oxygen sensor to make adjustments to the air to fuel ratio, which in turn will either increase or decrease the amount of oxygen present in the exhaust gas therefore controlling the chemical reactions in the catalytic converter. 
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • World Resources Institute http://www.wri.org/wri/wr-98-99/airpoll.htm
  • L

    1. 1. Transportation Issues
    2. 2. US Cars and Drivers <ul><li>US Population: </li></ul><ul><li>300 million </li></ul><ul><li>Licensed drivers </li></ul><ul><li>190 million </li></ul><ul><li>Cars and light trucks. </li></ul><ul><li>210 million </li></ul>
    3. 3. US Cars and Drivers <ul><li>We spend $20 out of every $100 of household $$ on our cars. </li></ul><ul><li>Very little travel ( 2% ) is by mass transit (buses and trains) </li></ul>
    4. 4. Problems <ul><li>Air pollution </li></ul><ul><li>Global Warming </li></ul><ul><li>Oil Imports </li></ul><ul><li>Gasoline Prices </li></ul><ul><li>Future Oil Supplies </li></ul>
    5. 5. What can we do?
    6. 6. Transportation: Air Pollution
    7. 7. Air Pollution – Sources
    8. 8. Internal Combustion Engine
    9. 9. Pollutants
    10. 10. Photochemical Smog
    11. 11. Ozone
    12. 12. Acid Rain
    13. 13. Acid Rain
    14. 14. The Environmental Protection Agency
    15. 15. Clean Air Acts 1955, 1963, 1970, 1990
    16. 16. Clean Air Act of 1990
    17. 17. Where are the problem areas?
    18. 18. How are emission standards achieved?
    19. 19. Catalytic Converter
    20. 20. Command and Control Strategy
    21. 21. Tailpipe Emissions Testing in Connecticut    
    22. 22. EPA Strategies Have Worked for Pollution Emission by cars. Even though vehicle miles increased by 150%, emission have substantially decreased.
    23. 23. Cars also emit CO2
    24. 24. Global Warming <ul><li>20 lb CO2 emitted for every gallon of gasoline consumed. </li></ul><ul><li>Transportation accounts for 25% of Global greenhouse gas emissions </li></ul>
    25. 25. Beyond Gasoline: Drive Less
    26. 26. Drive Less - Walk
    27. 27. Drive Less - Bicycle
    28. 28. Drive Less – Mass Transit
    29. 29. Drive Less - Subway
    30. 30. Drive Less - Carpool
    31. 31. Drive Less – Urban Planning
    32. 32. Drive Less – Summary <ul><li>Many people like flexibility and safety of cars </li></ul><ul><li>Many people like suburbs . </li></ul><ul><li>Mass transit systems requires large $$ investments . </li></ul><ul><li>Will take many years to transform suburbs into “new towns” </li></ul><ul><li>Part of the solution, but not the whole solution. </li></ul>
    33. 33. Beyond Gasoline: Biofuels
    34. 34. Ethanol
    35. 35. Gasohol (E10)
    36. 36. E85 – alternate fuel
    37. 37. Flex Fuel Vehicle
    38. 38. Brazil <ul><li>Sugar cane </li></ul><ul><li>Gas stations have E25 or E100 </li></ul>
    39. 39. Ethanol from Cellulose
    40. 40. Biodiesel
    41. 41. Biodiesel Fuel <ul><li>Processed diesel fuel derived from biological sources. </li></ul><ul><li>Used in unmodified diesel engines. </li></ul>
    42. 42. Limitations <ul><li>B20 - unmodified diesel engines </li></ul><ul><li>B100 - requires modifications </li></ul><ul><li>Gelling problem </li></ul>
    43. 43. Beyond Gasoline: Concept Cars
    44. 44. EV <ul><li>Electric Cars have not been successful. </li></ul><ul><ul><li>Large heavy batteries </li></ul></ul><ul><ul><li>Short driving range </li></ul></ul><ul><ul><li>Slow refueling (recharging) process. </li></ul></ul>
    45. 45. GM EV-1 <ul><li>Produced by GM from 1996-199 . </li></ul>
    46. 46. Tesla <ul><li>Tesla Roadster may represent a new direction . </li></ul><ul><ul><li>Uses new lighter batteries. </li></ul></ul><ul><ul><li>Expensive. </li></ul></ul>
    47. 47. GM Volt <ul><li>Li-Ion batteries and a gasoline engine. </li></ul><ul><li>The gasoline engine will run a generator to recharge the batteries, but will not directly power the vehicle. ( no gasoline motor ) </li></ul>
    48. 48. Fuel Cell Vehicles
    49. 49. Internal Combustion Engine <ul><li>Engine – 20% efficient </li></ul><ul><li>Only 20% of gasoline energy is converted to motion. </li></ul>
    50. 50. Fuel Cells and the Hydrogen Economy <ul><li>Fuels Cells use hydrogen to produce electrical energy. They do not burn hydrogen. </li></ul><ul><li>2H 2 +O 2  2H 2 O + energy </li></ul><ul><li>Fuel cells could be used to power cars with hydrogen as the fuel. </li></ul><ul><li>Clean fuel </li></ul>
    51. 51.                                                                                                       
    52. 52. Barriers to Hydrogen Cars <ul><li>Still in development </li></ul><ul><li>Expensive </li></ul><ul><li>On-vehicle storage of hydrogen fuel </li></ul><ul><li>Availability of hydrogen fuel </li></ul><ul><li>Infrastructure </li></ul>
    53. 53. Hydrogen Sources <ul><li>Steam reforming of natural gas: </li></ul><ul><li>CH 4 +2H 2 O  CO 2 + 4H 2 </li></ul><ul><li>Electrolysis : </li></ul><ul><li>2H 2 O + energy  2H 2 + O 2 </li></ul>
    54. 54. Energy Source for Electrolyzer <ul><li>Electrolysis requires energy. </li></ul><ul><li>Energy could come from Solar, Nuclear, or Wind. </li></ul><ul><li>In the short term, it would probably come from coal . </li></ul>
    55. 55. Beyond Gasoline: Fuel Economy
    56. 56. CAFE Standards Corporate Average Fuel Economy Mileage requirements for new vehicles
    57. 57. Current CAFE Standards <ul><li>27.5 mpg for passenger automobiles </li></ul><ul><li>20.7 mpg for light trucks & SUVs </li></ul>
    58. 58. How do we make cars that use less gasoline? <ul><li>Reduce wind drag </li></ul><ul><li>Reduce weight </li></ul><ul><li>More efficient engines and drive trains </li></ul>
    59. 59. Hybrid Electric Vehicle (HEV) <ul><li>Gasoline Engine </li></ul><ul><li>Electric motor </li></ul><ul><li>Does not need to be recharged </li></ul>
    60. 60. Hybrid Electric Vehicle (HEV)
    61. 61. Some Examples of 2008 Fuel Efficient Models
    62. 62. Toyota Prius <ul><li>Sedan </li></ul><ul><li>$22,200 </li></ul><ul><li>Hybrid </li></ul><ul><li>48 mpg </li></ul><ul><li>110 hp </li></ul>
    63. 63. Plug-In Hybrid (PHEV)
    64. 64. Honda Civic Hybrid <ul><li>Sedan </li></ul><ul><li>$22,600 </li></ul><ul><li>Hybrid </li></ul><ul><li>45 mpg </li></ul><ul><li>110 hp </li></ul>
    65. 65. Toyota Yaris Liftback <ul><li>Sedan </li></ul><ul><li>$11,000 </li></ul><ul><li>Gasoline </li></ul><ul><li>40 mpg </li></ul><ul><li>106hp </li></ul>
    66. 66. Honda Fit <ul><li>5-Door </li></ul><ul><li>$13,900 </li></ul><ul><li>Gasoline </li></ul><ul><li>37 mpg </li></ul><ul><li>109 hp </li></ul>
    67. 67. Honda Civic EX <ul><li>Sedan </li></ul><ul><li>$18,700 </li></ul><ul><li>Gasoline </li></ul><ul><li>37 mpg </li></ul><ul><li>140 hp </li></ul>
    68. 68. Ford Escape Hybrid <ul><li>SUV </li></ul><ul><li>$26,000 </li></ul><ul><li>Hybrid </li></ul><ul><li>30 mpg </li></ul><ul><li>230 hp </li></ul>
    69. 69. How long does it take to change the US auto fleet? <ul><li>210 million cars and light trucks in US </li></ul><ul><li>19 million new cars and trucks each year </li></ul><ul><li>200,000 new HEVs in 2005. </li></ul><ul><li>Vehicles last 140,000 miles or 10 years </li></ul><ul><li>Changing rolling stock takes several years. </li></ul>
    70. 70. Policies – Feebate <ul><li>Extra fee to buy a gasoline SUV </li></ul><ul><li>Rebate when buying a HEV </li></ul><ul><li>Nissan Armada: 13 mpg </li></ul>
    71. 71. Links <ul><li>http://www.nrel.gov/learning/re_biofuels.html </li></ul><ul><li>http://afdcmap2.nrel.gov/locator/FindPane.asp </li></ul><ul><li>http://gm-volt.com/ </li></ul><ul><li>http://world.honda.com/FuelCell/ </li></ul><ul><li>http://www.fueleconomy.gov/ </li></ul>

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