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2.0b Comparative Pollution. Frank R. Leslie, B. S. E. E., M. S. Space Technology, IEEE LS 1/19/10, Rev. 2.2.3 fleslie @fit.edu; (321) 674-7377 www.fit.edu/~fleslie. http://my.fit.edu/~fleslie/CourseRE/ClassPres/ClassHTM/RE020bPollution_files/frame.htm. 2b Overview of Pollution.
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2.0b Comparative Pollution Frank R. Leslie, B. S. E. E., M. S. Space Technology, IEEE LS 1/19/10, Rev. 2.2.3 fleslie @fit.edu; (321) 674-7377 www.fit.edu/~fleslie http://my.fit.edu/~fleslie/CourseRE/ClassPres/ClassHTM/RE020bPollution_files/frame.htm
2b Overview of Pollution • Many forms of energy conversion, primarily combustion, create pollution of air, water, or soil through gases, water discharges, etc. • Temperature changes to the environment may also be considered thermal pollution (heat in air or water) • Fossil fuel combustion produces NOx, SO2, CO2, etc. • Wind and solar energy are produced without pollution, but making the energy converters may have these byproducts (making steel, for example) • Tropical hydroelectric dam reservoirs produce some methane and carbon dioxide through decomposition of organic matter and the displaced forest • Noise or “viewscape” pollution draw protests 100119
2b.1 Why does Pollution Matter? • It’s not the pollution, it’s what it does! • Human costs • Health: Lung damage, cancer, kidney failure, vision • Accidents: Impaired driver visibility ahead on road • Nonhuman costs • Acid rain affects fish and trees • Lowered crop growth (except for CO2) • Building, monument, or other surface damage • Global • Global warming and climate change correlated with CO2 • Costs of pollution are usually not in the energy cost but are externalities! 100105
2b.2 Air, Land, and Water • Air • Power plant emissions of NOx, SO2, CO2, Hg, VOCs affect public health • Exhaust gases and soot from “oil” and coal transportation vehicles • Diesel exhaust also contains <2.5 micron particulates that cause lung disease by penetrating deep into the alveoli of the lungs • Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs), Sulphur hexafluoride (SF6) are others • Land • Runoff from mining of coal and oil/gas drilling; city streets and lawns, animals • Spills from chemicals used at energy plants • Pipeline failures or vandalism (Alaska shooting) • Water • Runoff from mining of coal and oil/gas drilling • Coal overburden dumped in nearby ravine; leaching of toxics into water • Thermal pollution affects river or lake creatures • Rain-washed oil flows from streets (Florida ice) into streams and lakes 100105
2b.3 Laws and Regulations • Governmental regulations affect energy costs and pollution levels • If enforcement is even-handed, no company has a business advantage in polluting; customer pays for reduction or fines • Major US Laws • 1970 Clean Air Act, amended 1977, 1990 • $6.49B Clear Skies Initiatives reduce deposition of SO2, NOx, and mercury yields $11B in benefits; but does not include CO2 • Major US Regulations • New Source Review (NSR) permits use of Best Available Control Technology (BACT) • EPA declares CO2 a pollutant to be regulated • Energy Policy Act of 1992 requires alternative fuel vehicles thus reducing dependence upon foreign sources of oil • Also reduces air pollution from the vehicles • EPA rules CO2 is a pollutant; restrictions likely 100119
2b.4 Pollution Monitoring • EPA (Environmental Protection Agency) monitors commercial mines and plants • Regulations ensure compliance by costly fines and possible imprisonment • Intentional polluters’ damage is first detected by appearance, smell, or public complaint • Power plant stacks must have pollution monitoring equipment to detect excess smoke • General air quality monitors sample the air to determine local pollution Methane, NOx, CO2 increasing since 1850 Ref.: Nova PBS 050110
2b.4.1 Pollution Monitoring Ref.: Nova PBS 070111
2b.5 Remediation Economics • The cost of pollution reduction determines how much effort will be expended to reduce it • Companies choose what to do based upon laws, regulations, trade studies, and profits • When a plant shuts down, will the facility be removed or converted to other uses? Who pays for this? • Rocky Flats Nuclear Arsenal area under consideration for wildlife refuge; now hosts National Wind Technology Center (NWTC; http://www.nrel.gov/wind/) • Hanford Nuclear Weapons Facilities has many tanks of radioactive materials that are being removed and cleaned • Super Fund Act required extensive cleanup of contaminated sites (remediation) 090109
2b.5.1 Mine Cleanup Figure 1. Distribution of coal-bearing strata in the Appalachian region study area. Dots indicate corehole locations. Green, areas having a low potential for acid mine drainage (AMD) from surface mining; red, areas having high AMD potential; yellow, areas having intermediate AMD potential. Ref.: USGS Fact Sheet 073-02Online Version 1.0 http://pubs.usgs.gov/fs/fs073-02/fs073-02.html Wind River WYUS Steel closed mine Photo F. Leslie ~2000 100105
2b.6 Nitrogen Dioxides or NOx • NOx forms smog at ground level decreasing visibility and health problems • 22 states affected by a court ruling must implement control measures for NOx emissions during the ozone season by May 2003 • Federal NOx Budget Trading Program to provide a cap-and-trade mechanism for Eastern US • Operators must restrict emissions to 0.15lb/MMBtu in a few years • Selective catalytic reduction (SCR) cuts stack gas pollution • SCR uses anhydrous ammonia to react with NOx • The ammonia delivery truck could crash and release toxic gas, so urea might be used instead • Ammonia “slip” or bypass must be restricted to below 3 ppm • SCR cost is ~$25/kW peak power • State Implementation Call (SIP) plans required to indicate how compliance will be achieved • As an example, Pennsylvania can emit no more than 50.000 tons/year by 2003, a 75% cutback from 1990 050110
2b.6.1 NOx and Hg Emissions Ref.: http://cta.policy.net/fact/4pbook.pdf 050110
2b.6.2 SO2 and CO2 Emission Sources Ref.: http://cta.policy.net/fact/4pbook.pdf 050110
2b.6.3 Selective Catalytic Reduction Process Process Description NOx, which consists primarily of NO with lesser amounts of NO2, is converted to nitrogen by reaction with NH3 over a catalyst in the presence of oxygen. A small fraction of the SO2, produced in the boiler by oxidation of sulfur in the coal, is oxidized to sulfur trioxide (SO3) over the SCR catalyst. In addition, side reactions may produce undesirable by-products: ammonium sulfate, (NH4)2SO4, and ammonium bisulfate, NH4HSO4. Ref.: DOE 070107
2b.7 Sulfur Dioxides, or SO2 & SO3 • SO2 causes soot, can cause asthma, lung cancer, respiratory aliments • Wet FGD processes can remove 95-98% of SO2 050110
2b.8 Mercury Pollution • Coal-burning power plants pollute with mercury that was in the coal, and the Federal Government doesn’t regulate this source • EPA capped emissions in 2005 in Clean Air Mercury Rule • Mercury can cause loss of hearing, blurred vision, kidney failure • Fish consume mercury in their food and concentrate it in their flesh, leading to warnings against people eating too much fish • Yet in 2004 & 2005, EPA loosened Hg emission standards! • Mercury in coal is vaporized and becomes an emission from power plants [recall that “power plants” have power that produces energy; power multiplied by time = energy] • The SCR process can remove up to 75% of the mercury from the exhaust gases --- a serendipitous effect • Washing coal can remove soluble pollutants before firing; more effective on sulfur than mercury • How is the wash water cleaned? Is it clean then? 100105
2b.9 Particulate Matter • Exhaust or stack gases contain “particulate matter” that adversely affects lungs; known as PM10 or PM2.5 in law (number is microns) • Utility plants use fabric bags to filter the gases, removing some 95% of particulate pollutants • Plants also use electrostatic precipitators that attract the PM or ash to the walls for collection and disposal • Wet-washing the stack gases also removes PM • Diesel engines can burn more cleanly if electronic emission controls adjust the fuel-air mixture during operation Photo: PPC Industries 080101
2b.11 Greenhouse Gases (GHG) • GHGs increase decomposition of ozone in the stratosphere • Less ozone absorption of ultraviolet light means more skin cancer • The “Greenhouse” analogy isn’t entirely accurate, but the nonscientists in the public can relate to the general concept • GHGs consist of pollutants such as NOx, SO2, VOCs, and CO2 • If Kyoto protocols were followed, the US would have to reduce GHG 7% below 1990 levels between 2008 and 2012 while population energy demands are increasing! • The US is some 13% above 1990 pollution levels, not below • Developing nations, China and India, are exempted from Kyoto, yet they are best suited to move towards a sustainable energy system • CO2 increases global warming but is not strictly a pollutant • A pollutant is any substance that causes harmful or unsuitable effects to air, soil, water, or natural resources • Underground storage of CO2 may be useful (sequestering) • Extracted CO2 could be used for carbonated beverages? (;-) 080101
2b.11.1 Greenhouse Gases (GHG) Principal GHG component of water vapor is not included? 051221
2b.12 Carbon Dioxide or CO2 • Recovering CO2 from power plants would reduce GHG • The oceans can sequester CO2 and buffer the amount present in the atmosphere, but there is a saturation limit • Manmade CO2 is 10 billion tonnes (metric tons) per year while Nature creates 200 billion tonnes per year 1 Tonne (metric ton) = 1,000 kilograms or 2,204.62 lbs Figure 32. Carbon Dioxide Emissions http://www.eia.doe.gov/aer/eh/frame.html 080101
2b.13 Nuclear Energy Plants St. Lucie Plant , FL - F. Leslie, 2003 • Nuclear plants create anguish among some people (anti-nuc activists) due to the Hiroshima view, yet nuclear plants cannot have a nuclear explosion • Radioactivity is too low at ~3 to 4% concentration • Nuclear weapons have concentrated >~90% fissile material • Concentrating uranium hexafluoride process same for fuel or weapons Three-Mile Island Plant near Harrisburg, PA --- PBS www.pbs.org 090109
2b.13 Nuclear Energy Plants www.pbs.org • The 1979 “China Syndrome” movie with Jane Fonda asserted that a meltdown of the core would melt all the way to China (Could this happen? Why or why not?) 090109
2b.13 Nuclear Energy Plants www.pbs.org • The “China Syndrome” movie created a public nonscientific impression • The Three-Mile Island event of 1979 caused ~100,000 people to flee the area; half the core was uncovered as water boiled off; no one died • The Three-Mile Island event of 1979 shows that nuclear power is unsafe because radioactive gases were released • The Three-Mile Island event of 1979 shows that nuclear power is safe because automatic safety features prevented a catastrophe • There are some 104 commercial reactors in 32 US states, and spent fuel is proposed to be moved by rail and truck to Yucca Mountain NM through many states and cities • The major environmental pollution hazard would be from spillage of the fuel rod materials during transport by road or rail vehicles • Now, terrorists might strike plants! What to do? What to do? • From my past industry anti-terrorist studies at Harris Corp., place protected material in one place by each plant and protect it at high expense with early-intrusion-detection alarms 080105
2b.14 How Energy Plants Compare www.epa.gov/cleanenergy/impacts * Only during system or components manufactureGeothermal Air conditioning might have refrigerant leaks (CFC or ammonia) 070111
2b Conclusion • Combustion energy sources emit pollutants; renewable sources emit none or much less • Wind and solar energy doesn’t pollute, but there may have been pollution from the making of the conversion equipment (a steel wind turbine tower) • Nuclear plants might emit accidental releases of radioactivity, but safe designs reduce this chance • Laws effect (cause) utility plant operations to reduce pollution; they remove economic disincentives to pollute • Emissions credit trading helps reduce pollution since there is an economic incentive to clean up emissions • “Cap-and-trade” or plain caps may be coming 090120
References: Books • Boyle, Godfrey. Renewable Energy: Power for a Sustainable Future, Second Ed. Oxford: Oxford Univ. Press, 452pp., 2004. • Boyle, Godfrey. Energy Systems and Sustainability, Oxford: Oxford Univ. Press, 620pp., 2003. • Brown, Lester R. State of the World 2000. NY: W.W.Norton, 276 pp., 2000. • ____________________________________________________________________ • Brower, Michael. Cool Energy. Cambridge MA: The MIT Press, 1992. 0-262-02349-0, TJ807.9.U6B76, 333.79’4’0973. • Duffie, John and William A. Beckman. Solar Engineering of Thermal Processes. NY: John Wiley & Sons, Inc., 920 pp., 1991 • Gipe, Paul. Wind Energy for Home & Business. White River Junction, VT: Chelsea Green Pub. Co., 1993. 0-930031-64-4, TJ820.G57, 621.4’5 • Patel, Mukund R. Wind and Solar Power Systems. Boca Raton: CRC Press, 1999, 351 pp. ISBN 0-8493-1605-7, TK1541.P38 1999, 621.31’2136 • Sørensen, Bent. Renewable Energy, Second Edition. San Diego: Academic Press, 2000, 911 pp. ISBN 0-12-656152-4. 060113
References: Websites, etc. http://www.epa.gov/ebtpages/pollutants.html http://www.energyjustice.net/coal/ http://www.nadir.org/nadir/initiativ/agp/free/imf/panama/2002/0830Bayano_Hydroelectric.htm http://www.pbs.org/wgbh/amex/three/timeline/index_2.html http://www.ecy.wa.gov/programs/air/NO_IDLE/No_IDLE.html ________________________________________________________ awea-windnet@yahoogroups.com. Wind Energy elist awea-wind-home@yahoogroups.com. Wind energy home powersite elist windenergyexperimenter@yahoogroups.com. Elist for wind energy experimenters www.dieoff.org. Site devoted to the decline of energy and effects upon population www.ferc.gov/ Federal Energy Regulatory Commission www.google.com/search?q=%22renewable+energy+course%22 solstice.crest.org/ 051221
References: Websites, etc. awea-windnet@yahoogroups.com. Wind Energy elist awea-wind-home@yahoogroups.com. Wind energy home powersite elist geothermal.marin.org/ on geothermal energy mailto:energyresources@egroups.com rredc.nrel.gov/wind/pubs/atlas/maps/chap2/2-01m.html PNNL wind energy map of CONUS windenergyexperimenter@yahoogroups.com. Elist for wind energy experimenters www.dieoff.org. Site devoted to the decline of energy and effects upon population www.ferc.gov/ Federal Energy Regulatory Commission www.hawaii.gov/dbedt/ert/otec_hi.html#anchor349152 on OTEC systems telosnet.com/wind/20th.html www.google.com/search?q=%22renewable+energy+course%22 solstice.crest.org/ dataweb.usbr.gov/html/powerplant_selection.html 0601121
Questions? Olin Engineering Complex 4.7 kW Solar PV Roof Array 090120