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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 protests100119
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!
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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
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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
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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
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Ref.: Nova PBS
Methane, NOx, CO2 increasing since 1850
2b.4.1 Pollution Monitoring
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Ref.: Nova PBS
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)
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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
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Wind River WYUS Steel closed mine Photo F. Leslie ~2000
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
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2b.6.1 NOx and Hg Emissions
Ref.: http://cta.policy.net/fact/4pbook.pdf
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2b.6.2 SO2 and CO2 Emission Sources
Ref.: http://cta.policy.net/fact/4pbook.pdf
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2b.6.3 Selective Catalytic Reduction Process
Ref.: DOE
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.
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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
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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?
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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
2b.9 Particulate Matter
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Photo: PPC Industries
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)
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Principal GHG component of water vapor is not included?
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
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Figure 32. Carbon Dioxide Emissions
http://www.eia.doe.gov/aer/eh/frame.html
1 Tonne (metric ton) = 1,000 kilograms or 2,204.62 lbs
www.pbs.org
2b.13 Nuclear Energy Plants
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
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St. Lucie Plant , FL - F. Leslie, 2003
Three-Mile Island Plant near Harrisburg, PA --- PBS
www.pbs.org
2b.13 Nuclear Energy Plants
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?)
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www.pbs.org
2b.13 Nuclear Energy Plants
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
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* Only during system or components manufactureGeothermal Air conditioning might have refrigerant leaks (CFC or ammonia)
2b.14 How Energy Plants Compare
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NOx SO2 CO CO2 Hg Methane Thermal Particulate Matte
r
“Fuel” Extraction
Fuel Residue
Coal Yes, 6 lb/MWh
Yes, 13lb/ MWh
little Yes, 2249 lb/ MWh
Yes Mine fumes
Yes Yes Yes
Deaths of miners
Ash, fly ash
Oil Yes, 4lb/ MWh
Yes, 12 lb/ MWh
Yes, vehicles
1672lb/ MWh
0.02 ppm
no Yes yes Yes Engine blowby, gases
Natural Gas
1.7 lb/ MWh
0.1 lb/ MWh
Yes 1135lb/ MWh
? NG~80% methane & burned
Yes Yes Yes
explosions
Very low if any
Wind * * * * * * Insignificant; no
no No (birds) Low speed wind
Solar * * * * * * ?radiation/ conduction from panels
no no darkness
Hydro * * * some * In reserv-oir
no no Affects downstream
no
Geo-thermal
* ? * * * ? Yes Salt? no
Brine spills Saline spills
Nuclear
* * * * * * Yes no Yes Spent fuel
www.epa.gov/cleanenergy/impacts
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
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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.
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References: Websites, etc.
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http://www.epa.gov/ebtpages/pollutants.htmlhttp://www.energyjustice.net/coal/http://www.nadir.org/nadir/initiativ/agp/free/imf/panama/2002/0830Bayano_Hydroelectric.htmhttp://www.pbs.org/wgbh/amex/three/timeline/index_2.htmlhttp://www.ecy.wa.gov/programs/air/NO_IDLE/No_IDLE.html________________________________________________________awea-windnet@yahoogroups.com. Wind Energy [email protected]. Wind energy home powersite [email protected]. Elist for wind energy experimenterswww.dieoff.org. Site devoted to the decline of energy and effects upon populationwww.ferc.gov/ Federal Energy Regulatory Commissionwww.google.com/search?q=%22renewable+energy+course%22solstice.crest.org/
References: Websites, etc.
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[email protected]. Wind Energy [email protected]. Wind energy home powersite elistgeothermal.marin.org/ on geothermal energymailto:[email protected] rredc.nrel.gov/wind/pubs/atlas/maps/chap2/2-01m.html PNNL wind energy map of CONUS [email protected]. Elist for wind energy experimenterswww.dieoff.org. Site devoted to the decline of energy and effects upon populationwww.ferc.gov/ Federal Energy Regulatory Commissionwww.hawaii.gov/dbedt/ert/otec_hi.html#anchor349152 on OTEC systemstelosnet.com/wind/20th.htmlwww.google.com/search?q=%22renewable+energy+course%22solstice.crest.org/dataweb.usbr.gov/html/powerplant_selection.html
Olin Engineering Complex 4.7 kW Solar PV Roof Array
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Questions?
