Advanced Placement Environmental Science Nonrenewable Energy Chapters 17 Living in the Environment, 14th Edition, Miller Advanced Placement Environmental Science A.C. Mosley High School Mrs. Dow

Case Study: Bitter Lessons from Chernobyl The world’s most serious nuclear power plant accident. April 26,1986 Ukraine part of the Soviet Union 30 people nearby died from radiation exposure 2,000 children developed thyroid cancer Estimated number of premature deaths ranging from 8,000 to 15,000. More than 100,000 people had to leave their homes. The accident happened because poor reactor design and human error. A series of explosions in one of the reactors blew the massive roof off a reactor building and flung radioactive debris and dust high into the atmosphere. A huge radioactive cloud spread over much of Belarus, Russia, Ukraine, and other parts of Europe and eventually encircled the planet. Clouds of radioactive material escaped into the atmosphere for 10 days. The surrounding environment and people were exposed to radiation levels about 100 times higher than those caused by the atomic bomb the United States dropped on Hiroshima, Japan, near the end of World War II. It was caused by poor reactor design and human error. In 2003 Ukraine officials downgraded the area in a 27- square kilometer(17 mile) radius from the reactor to a “zone with high risk” to allow those willing to accept the health risks to return home. The accident exposed more than a half a million people to dangerous levels of radioactivity and has caused several thousands cases of thyroid cancer. The total cost of the accident is at least $140 billion according to the U.S, Dept. of Energy and could eventually reach $358 billion according to Ukraine officials.

Crane for moving fuel rods Steam generator Cooling pond Turbines 2 Almost all control rods were removed from the core during experiment. 3 Automatic safety devices that shut down the reactor when water and steam levels fall below normal and turbine stops were shut off because engineers didn’t want systems to “spoil” experiment. Crane for moving fuel rods 1 Emergency cooling system was turned off to conduct an experiment. Steam generator Cooling pond Turbines Radiation shields Reactor Water pumps The accident happened because engineers turned off most of the reactor’s safety and warning system to keep from interfering with an unauthorized safety experiment. Also the design was inadequate (there were no secondary containment shell, as in Western- style reactors), and a design flaw led to unstable operations at low power. After the explosion, crews exposed themselves to lethal doses of radiation to put out fires and encase the shattered reactor in a hasily constructed tomb. This 19- story tomb is crumbling and leaking radioactive material into the surrounding area. In 2003 $ 85 million was provided to make emergency repairs and an additional $ 750 million is needed to build a new protective shield around the damaged reactor. 5 Reactor power output was lowered too much, making it too difficult to control. 4 Additional water pump to cool reactor was turned on. But with low power output and extra drain on system, water didn’t actually reach reactor.

1. Energy Resources 2. Oil 3. Natural Gas 4. Coal 5. Nuclear Energy www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Energy Sources Modern society requires large quantities of energy that are generated from the earth’s natural resources. Primary Energy Resources: The fossil fuels(oil, gas, and coal), nuclear energy, falling water, geothermal, and solar energy. Secondary Energy Resources: Those sources which are derived from primary resources such as electricity, fuels from coal, (synthetic natural gas and synthetic gasoline), as well as alcohol fuels. www.lander.edu/rlayland/Chem%20103/chap_12.ppt

Thermodynamics The laws of thermodynamics tell us two things about converting heat energy from steam to work: 1) The conversion of heat to work cannot be 100 % efficient because a portion of the heat is wasted. 2) The efficiency of converting heat to work increases as the heat temperature increases. 1st law of thermodynamics-Energy is neither created nor destroyed, But it may be converted from one form to another 2nd law-When energy is changed from one form to another Some of the useful energy is always degraded to lower-quality, more dispersed, less useful energy In every transformation, some energy is converted to heat Also known as Law of Entropy www.lander.edu/rlayland/Chem%20103/chap_12.ppt

Energy Units and Use Btu (British thermal unit) - amount of energy required to raise the temperature of 1 lb of water by 1 ºF. cal (calorie) - the amount of energy required to raise the temperature of 1 g of water by 1 ºC. Commonly, kilocalorie (kcal) is used. 1 Btu = 252 cal = 0.252 kcal 1 Btu = 1055 J (joule) = 1.055 kJ 1 cal = 4.184 J www.lander.edu/rlayland/Chem%20103/chap_12.ppt

Energy Units and Use Two other units that are often seen are the horsepower and the watt. These are not units of energy, but are units of power. 1 watt (W) = 3.412 Btu / hour 1 horsepower (hp) = 746 W Watt-hour - Another unit of energy used only to describe electrical energy. Usually we use kilowatt-hour (kW-h) since it is larger. quad (Q) - used for describing very large quantities of energy. 1 Q = 1015 Btu www.lander.edu/rlayland/Chem%20103/chap_12.ppt

Evaluating Energy Resources 17.1 99% of energy heating earth is from sun Nuclear fusion reactor Indirect resources (wind, flowing water, biomass) 1% comes mostly from nonrenewable mineral resources obtained from the earth’s crust Primarily carbon-containing fossil fuels Oil Natural gas coal Without solar energy the Earth average temperature would be –240Celsius ( -400 Fahrenheit). Solar Energy comes from nuclear fusion of hydrogen atoms that make-up the sun’s mass. Thu life on earth is made possible by a giganic nuclear fusion reactor safety located in space about 93 million miles away.

Energy resources removed from the earth’s crust include: oil, natural gas, coal, and uranium www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Global energy consumption 84% commercial energy consumed is from nonrenewable sources (fossil fuels, nuclear energy) Roughly half of the world’ people in developing countries burn wood/charcoal Many face shortage Premature deaths from burning indoors ** renewable if used slower than replaced Most of the biomass is collected by users and not sold in the marketplace. Thus the actual percentage of renewable biomass used is higher than the 10% figure shown on the next slide.

A person in the U.S. consume as much energy as a person in the poorest country consumes in a year 2004 (U.S. 24% of worlds energy w/4.6% of population) India (3% of worlds energy/16% of population) 94% of U.S. energy from nonrenewable Depleted by 2050 or 2100

Types of Commercial Energy the world depends on Nuclear power 6% Hydropower, geothermal, solar, wind 6% Natural Gas 22% RENEWABLE 16% Biomass 10% Coal 23% Oil 33% 84 % of the commercial energy comes from nonrenewable resources: 78% from fossil fuels, 6 nuclear energy. The remaining 16% comes from renewable resources- biomass(10%), hydropower(5%), and a combination of geothermal, wind, and solar energy (1%). NONRENEWABLE 84% Types of Commercial Energy the world depends on World

Commercial energy the U.S. depends on Nuclear power 8% Hydropower geothermal solar, wind 3% Natural Gas 24% RENEWABLE 6% Coal 23% Oil 39% The United States in the world’s largest energy user, In 2004, with only 4.6% of the population, the U. S. used 24% of the world’s commercial energy. In contrast with India, w/ 16% of the population, they used about 3% of the world’s commercial energy. About 94% of the commercial energy used in the U.S comes from nonrenewable energy resources( 86% from fossil fuels and 8% nuclear Power) the remaining 6% comes from moslty renewable biomass and hydropower. NONRENEWABLE 94% Biomass 3% United States Commercial energy the U.S. depends on

Global Energy consumption 60 History Projections Oil 50 Natural gas 40 Coal Energy consumption (quadrillion Btus) Nuclear 30 Nonhydro renewable 20 Renewable hydro 10 Global energy consumption by fuel types, 1970-2003, with projections to 2020 (A Btu is a British Thermal Unit, a standard measure of heat for value comparisons of various fuels.) 1970 1980 1990 2000 2010 2020 Year

Energy consumption (quadrillion Btus) U.S. Energy consumption 60 History Projections Oil 50 Natural gas 40 Coal Energy consumption (quadrillion Btus) Nuclear 30 Nonhydro renewable 20 Renewable hydro 10 Energy consumption by fuel in the US 1970-2003, w/ projections to 2020. 1970 1980 1990 2000 2010 2020 Year

Evaluating Energy Resources U.S. has 4.6% of world population; uses 24% of the world’s energy; 84% from nonrenewable fossil fuels (oil, coal, & natural gas); 7% from nuclear power; 9% from renewable sources (hydropower, geothermal, solar, biomass).

Changes in U.S. Energy Use www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Fossil fuel burning 80% of pollution, 80% of CO2 emissions In U.S Fossil fuel burning 80% of pollution, 80% of CO2 emissions Fossil fuel & nuclear energy plants receive government subsidies For many energy experts the need to use cleaner and less climate-disrupting (non-carbon) energy resources – not the depletion of fossil fuels – is the driving force behind the projected transition to a solar - hydrogen energy age in the US and in other parts of the world before the end of this century. If we want energy alternative such as solar and hydrogen to become more dominant they must be nurtured by subsidies and tax breaks. A political problem is that Fossil fuels and nuclear power industries have been receiving governmental subsidies for over 50 years understandable do not want to give them up. And they use their political power to keep them. As a citizen, you can play an important role in helping decide the energy future for yourself and future generation. Indeed, it is one of the most important political act you can undertake. This explains why you should understand the advantages and disadvantages of our energy options.

What energy should be promoted? 50 years to phase in new energy alternatives How much available in the future? Net Energy Yield? Cost? Govt. subsidies? Dependence affect global economy? Vulnerable to terrorism? Transportation/climate cost? It usually take 50 years and huge investment to phase in new energy alternatives to the point where they provide 10-20% of total energy use.

Net energy Estimating total energy available minus energy used, wasted in finding, processing, concentrating, transporting It takes energy to make energy.The second law of thermodynamics tells us that some of it will always be wasted and degraded to lower- quality energy source.

Space Heating Passive solar 5.8 Natural gas 4.9 Oil 4.5 Active solar 1.9 Coal gasification 1.5 Electric resistance heating (coal-fired plant) 0.4 Electric resistance heating (natural-gas-fired plant) We express net energy as the ratio of useful energy produced to the useful energy used to produce it. For example, suppose that for every 10 units of energy in oil in the ground we have to use and waste 8 units of energy to find, extract, process, and transport the oil to users. Then we have 2 useful units of useful energy available from every 10 units of energy in the oil. The net energy ratio would be 10:8, or 1.25. The higher the ratio, the greater the net energy. When the ratio is less than 1, there is a net energy loss. Currently oil has a high net energy ratio because much of it comes from large, accessible, and cheap-to-extract deposits such as those in the Middle East. When those are depleted, the net energy ratio of oil will decline and prices will rise. 0.4 Electric resistance heating (nuclear plant) 0.3 Net energy ratios for various energy systems over their estimated lifetimes.

High-Temperature Industrial Heat 28.2 Surface-mined coal Underground-mined coal 25.8 Natural gas 4.9 Oil 4.7 Coal gasification 1.5 Direct solar (highly concentrated by mirrors, heliostats, or other devices) 0.9 Net energy ratios for various energy systems over their estimated lifetimes

Gasoline (refined crude oil) 4.1 Transportation Natural gas 4.9 Gasoline (refined crude oil) 4.1 Biofuel (ethyl alcohol) 1.9 Coal liquefaction 1.4 Oil shale 1.2 Net energy ratios for various energy systems over their estimated lifetimes

Fossil Fuels Fossil fuels originated from the decay of living organisms millions of years ago, and account for about 80% of the energy generated in the U.S. The fossil fuels used in energy generation are: Natural gas, which is 70 - 80% methane (CH4) Liquid hydrocarbons obtained from the distillation of petroleum Coal - a solid mixture of large molecules with a H/C ratio of about 1 www.lander.edu/rlayland/Chem%20103/chap_12.ppt

Problems with Fossil Fuels Fossil fuels are nonrenewable resources At projected consumption rates, natural gas and petroleum will be depleted before the end of the 21st century Impurities in fossil fuels are a major source of pollution Burning fossil fuels produce large amounts of CO2, which contributes to global warming www.lander.edu/rlayland/Chem%20103/chap_12.ppt

2. Oil 1. Energy Resources 3. Natural Gas 4. Coal 5. Nuclear Energy www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Oil Deposits of crude oil often are trapped within the earth's crust and can be extracted by drilling a well Fossil fuel, produced by the decomposition of deeply buried organic matter from plants & animals Crude oil: complex liquid mixture of hydrocarbons, with small amounts of S, O, N impurities How Oil Drilling Works by Craig C. Freudenrich, Ph.D.

Sources of Oil Organization of Petroleum Exporting Countries (OPEC) -- 13 countries have 67% world reserves: Algeria, Ecuador, Gabon, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, United Arab Emirates, & Venezuela Other important producers: Alaska, Siberia, & Mexico. www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Oil in U.S. 2.3% of world reserves uses nearly 30% of world reserves; 65% for transportation; increasing dependence on imports. www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Locations of major known deposits in U. S. Arctic Ocean Prudhoe Bay Coal Beaufort Sea ALASKA Gas Trans Alaska oil pipeline Arctic National Wildlife Refuge Oil Prince William Sound Valdez High potential areas Gulf of Alaska CANADA Locations of major known deposits in U. S. Geologists do not expect to find very much new oil and natural gas in North America. Grand Banks Pacific Ocean UNITED STATES Atlantic Ocean MEXICO

LOUISIANA ALABAMA GEORGIA MISSISSIPPI TEXAS FLORIDA Offshore drilling for oil accounts for about ¼th of U.S. oil production About 9 out of 10 barrels of this oil comes from the Gulf of Mexico, where there are 4,000 drilling platforms and 33,000 miles of underwater pipelines. Today’s global oil industry is a marvel of technology and management skills. Satellites help find promising oil deposits. Sophisticated computers and software programs analyze seismic data to create 3-D images of the Earth’s interior. Computers and software programs analyze seismic data to create 3-D images of the earth’s interior. High tech equipment can drill oil and natural gas wells to a depth of almost 4 miles. Drilling platforms on the high seas are engineering marvels that can with stand hurrican winds. GULF OF MEXICO Active drilling sites Offshore drilling for oil accounts for about ¼th of U.S. oil production

Low oil prices have stimulated economic growth, they have discouraged / prevented improvements in energy efficiency and alternative technologies favoring renewable resources. www.bio.miami .edu/beck/esc10 1/Chapter14&1 5.ppt

Comparison of CO2 emitted by fossil fuels and nuclear power. Burning any fossil fuel releases carbon dioxide into the atmosphere and thus promotes global warming. Comparison of CO2 emitted by fossil fuels and nuclear power. www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Trade-Offs Advantages Disadvantages Conventional Oil Advantages Disadvantages Ample supply for 42-93 years Low cost (with huge subsidies) High net energy yield Easily transported within and between countries Low land use Technology is well developed Efficient distribution system Need to find substitute within 50 years Artifically low price encourages waste and discourages search for alternative Air pollution when burned Releases CO2 when burned Moderate water pollution

Drilling for Oil and Natural Gas National Wildlife Refuge Trade-Offs Drilling for Oil and Natural Gas In Alaska’s Arctic National Wildlife Refuge Advantages Disadvantages Could increase U.S oil and natural gas supplies Could reduce oil imports slightly Would bring jobs and oil revenue to Alaska May lower oil prices slightly Oil companies have developed Alaskan Oil fields without significant harm New drilling techniques will leave little environ- mental impact Only 19% of finding oil equal to what U.S. consumes in 7-24 months Too little potential oil to significantly reduce oil imports Costs too high and potential oil supply too little to lower energy prices Studies show considerable oil spills and other environmental damage from Alaskan oil fields Potential degradation of refuge not worth the risk Unnecessary if improved slant drilling allows oil to be drilled from outside the refuge

Oil Crude oil is transported to a refinery where distillation produces petrochemicals How Oil Refining Works by Craig C. Freudenrich, Ph.D.

Oil Shale Rock / shale oil Big U.S. oil shale projects have been cancelled because of excessive costs. Oil Shale Rock / shale oil

Alternatives Bitumen (oil w/sulfur content) Oil sand or tar + clay, sand, water, & organic material Created with bacteria & water from escaped oil Requires great energy (low NPP) Canada 1/10 reserve Reduce dependence on middle east Extreme pollution when extracted Oil shale another source (kerogen) – huge supply, but expensive

Trade-Offs Advantages Disadvantages Heavy Oils from Oil Shale and Oil Sand Advantages Disadvantages High cost (oil shale) Moderate cost (oil sand) Low net energy yield Large potential supplies, especially oil sands in Canada Large amount of water needed for processing Easily transported within and between countries Severe land disruption from surface mining Water pollution from mining residues Efficient distribution system in place Air pollution when burned Technology is well developed CO2 emissions when burned

3. Natural Gas 1. Energy Resources 2. Oil 4. Coal 5. Nuclear Energy www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Natural Gas - Fossil Fuel Mixture 50–90% Methane (CH4) Ethane (C2H6) Propane (C3H8) Butane (C4H10) Hydrogen sulfide (H2S) www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Sources of Natural Gas Russia & Kazakhstan - almost 40% of world's supply. Iran (15%), Qatar (5%), Saudi Arabia (4%), Algeria (4%), United States (3%), Nigeria (3%), Venezuela (3%); 90–95% of natural gas in U.S. domestic (~411,000 km = 255,000 miles of pipeline). www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

billion cubic metres

Conventional Natural Gas Trade-Offs Conventional Natural Gas Advantages Disadvantages Ample supplies (125 years) Nonrenewable resource High net energy yield Releases CO2 when burned Low cost (with huge subsidies) Methane (a greenhouse gas) can leak from pipelines Less air pollution than other fossil fuels Difficult to transfer from one country to another Lower CO2 emissions than other fossil fuels Shipped across ocean as highly explosive LNG Moderate environmental impact Sometimes burned off and wasted at wells because of low price Low land use Easily transported by pipeline Requires pipelines Good fuel for fuel cells and gas turbines

Natural Gas Experts predict increased use of natural gas during this century

Natural Gas When a natural gas field is tapped, propane and butane are liquefied and removed as liquefied petroleum gas (LPG) The rest of the gas (mostly methane) is dried, cleaned, and pumped into pressurized pipelines for distribution Liquefied natural gas (LNG) can be shipped in refrigerated tanker ships

4. Coal 1. Energy Resources 2. Oil 3. Natural Gas 5. Nuclear Energy www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Coal: Supply and Demand Coal exists in many forms therefore a chemical formula cannot be written for it. Coalification: After plants died they underwent chemical decay to form a product known as peat Over many years, thick peat layers formed. Peat is converted to coal by geological events such as land subsidence which subject the peat to great pressures and temperatures. www.lander.edu/rlayland/Chem%20103/chap_12.ppt

garnero101.asu.edu/glg101/Lectures/L37.ppt

Increasing heat and carbon content Increasing moisture content Peat (not a coal) Lignite (brown coal) Bituminous Coal (soft coal) Anthracite (hard coal) Heat Heat Heat Pressure Pressure Pressure Partially decayed plant matter in swamps and bogs; low heat content Low heat content; low sulfur content; limited supplies in most areas Extensively used as a fuel because of its high heat content and large supplies; normally has a high sulfur content Highly desirable fuel because of its high heat content and low sulfur content; supplies are limited in most areas

Ranks of Coal Lignite: A brownish-black coal of low quality (i.e., low heat content per unit) with high inherent moisture and volatile matter. Energy content is lower 4000 BTU/lb. Subbituminous: Black lignite, is dull black and generally contains 20 to 30 percent moisture Energy content is 8,300 BTU/lb. Bituminous: most common coal is dense and black (often with well-defined bands of bright and dull material). Its moisture content usually is less than 20 percent. Energy content about 10,500 Btu / lb. Anthracite :A hard, black lustrous coal, often referred to as hard coal, containing a high percentage of fixed carbon and a low percentage of volatile matter. Energy content of about 14,000 Btu/lb. www.uvawise.edu/philosophy/Hist%20295/ Powerpoint%5CCoal.ppt

PEAT LIGNITE garnero101.asu.edu/glg101/Lectures/L37.ppt

BITUMINOUS ANTHRACITE garnero101.asu.edu/glg101/Lectures/L37.ppt

Main Coal Deposits Bituminous Subbituminous Lignite Anthracite www.lander.edu/rlayland/Chem%20103/chap_12.ppt

Advantages and Disadvantages Pros Most abundant fossil fuel Major U.S. reserves 300 yrs. at current consumption rates High net energy yield Cons Dirtiest fuel, highest carbon dioxide Major environmental degradation Major threat to health © Brooks/Cole Publishing Company / ITP www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Trade-Offs Advantages Disadvantages Coal Advantages Disadvantages Ample supplies (225–900 years) Very high environmental impact Severe land disturbance, air pollution, and water pollution High net energy yield Low cost (with huge subsidies) High land use (including mining) Mining and combustion technology well-developed Severe threat to human health High CO2 emissions when burned Air pollution can be reduced with improved technology (but adds to cost) Releases radioactive particles and mercury into air

Coal Coal gasification ® Synthetic natural gas (SNG) Coal liquefaction ® Liquid fuels Disadvantage Costly High environmental impact

garnero101.asu.edu/glg101/Lectures/L37.ppt

Sulfur in Coal When coal is burned, sulfur is released primarily as sulfur dioxide (SO2 - serious pollutant) Coal Cleaning - Methods of removing sulfur from coal include cleaning, solvent refining, gasification, and liquefaction Scrubbers are used to trap SO2 when coal is burned Two chief forms of sulfur is inorganic (FeS2 or CaSO4) and organic (Sulfur bound to Carbon) www.lander.edu/rlayland/Chem%20103/chap_12.ppt

Acid Mine Drainage The impact of mine drainage on a lake after receiving effluent from an abandoned tailings impoundment for over 50 years

Relatively fresh tailings in an impoundment. http://www.earth.uwaterloo.ca/services/whaton/s06_amd.html The same tailings impoundment after 7 years of sulfide oxidation. The white spots in Figures A and B are gulls.

Mine effluent discharging from the bottom of a waste rock pile

Shoreline of a pond receiving AMD showing massive accumulation of iron hydroxides on the pond bottom

Groundwater flow through a tailings impoundment and discharging into lakes or streams.

5. Nuclear Energy 1. Energy Resources 2. Oil 3. Natural Gas 4. Coal www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Nuclear Energy In a conventional nuclear power plant a controlled nuclear fission chain reaction heats water produce high-pressure steam that turns turbines generates electricity.

Nuclear Energy Controlled Fission Chain Reaction neutrons split the nuclei of atoms such as of Uranium or Plutonium release energy (heat) www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Controlled Nuclear Fission Reaction cstl-cst.semo.edu/bornstein/BS105/ Energy%20Use%20-%203.ppt

www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Radioactivity Radioactive decay continues until the the original isotope is changed into a stable isotope that is not radioactive Radioactivity: Nuclear changes in which unstable (radioactive) isotopes emit particles & energy www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Radioactivity Types Sources of natural radiation Alpha particles consist of 2 protons and 2 neutrons, and therefore are positively charged Beta particles are negatively charged (electrons) Gamma rays have no mass or charge, but are a form of electromagnetic radiation (similar to X-rays) Sources of natural radiation Soil Rocks Air Water Cosmic rays www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Relative Doses from Radiation Sources cstl-cst.semo.edu/bornstein/BS105/ Energy%20Use%20-%203.ppt

Half-Life The time needed for one-half of the nuclei in a radioisotope to decay and emit their radiation to form a different isotope Half-time emitted Uranium 235 710 million yrs alpha, gamma Plutonium 239 24.000 yrs alpha, gamma During operation, nuclear power plants produce radioactive wastes, including some that remain dangerous for tens of thousands of years www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Diagram of Radioactive Decay cstl-cst.semo.edu/bornstein/BS105/ Energy%20Use%20-%203.ppt

Effects of Radiation Genetic damages: from mutations that alter genes Genetic defects can become apparent in the next generation Somatic damages: to tissue, such as burns, miscarriages & cancers www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt

Radioactive Waste 1. Low-level radiation (Gives of low amount of radiation) Sources: nuclear power plants, hospitals & universities 1940 – 1970 most was dumped into the ocean Today deposit into landfills 2. High-level radiation (Gives of large amount of radiation) Fuel rods from nuclear power plants Half-time of Plutonium 239 is 24000 years No agreement about a safe method of storage www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Radioactive Waste 1. Bury it deep underground. Problems: i.e. earthquake, groundwater… 2. Shoot it into space or into the sun. Problems: costs, accident would affect large area. 3. Bury it under the Antarctic ice sheet. Problems: long-term stability of ice is not known, global warming 4. Most likely plan for the US Bury it into Yucca Mountain in desert of Nevada Cost of over $ 50 billion 160 miles from Las Vegas Transportation across the country via train & truck www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Figure 17-29 Page 374 Nuclear power plants Yucca Mountain Railroads Highways

Yucca Mountain www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt

Plutonium Breeding 238U is the most plentiful isotope of Uranium Non-fissionable - useless as fuel Reactors can be designed to convert 238U into a fissionable isotope of plutonium, 239Pu www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt

Conversion of 238U to 239Pu Under appropriate operating conditions, the neutrons given off by fission reactions can "breed" more fuel, from otherwise non-fissionable isotopes, than they consume Source: http://www.ccnr.org/breeding_ana.html www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt

Reprocess Nuclear Fuel During the operation of a nuclear reactor the uranium runs out Accumulating fission products hinder the proper function of a nuclear reactor Fuel needs to be (partly) renewed every year Source: http://www.antenna.nl/nvmp/pluto3.htm www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt

Plutonium in Spent Fuel Spent nuclear fuel contains many newly formed plutonium atoms Miss out on the opportunity to split Plutonium in nuclear waste can be separated from fission products and uranium Cleaned Plutonium can be used in a different Nuclear Reactor Source: http://www.antenna.nl/nvmp/pluto3.htm www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt

Conventional Nuclear Fuel Cycle Trade-Offs Conventional Nuclear Fuel Cycle Advantages Disadvantages Large fuel supply High cost (even with large subsidies) Low environmental impact (without accidents) Low net energy yield High environmental impact (with major accidents) Emits 1/6 as much CO2 as coal Moderate land disruption and water pollution (without accidents) Catastrophic accidents can happen (Chernobyl) No widely acceptable solution for long-term storage of radioactive wastes and decommissioning worn-out plants Moderate land use Low risk of accidents because of multiple safety systems (except in 35 poorly designed and run reactors in former Soviet Union and Eastern Europe) Subject to terrorist attacks Spreads knowledge and technology for building nuclear weapons

Nuclear Energy Concerns about the safety, cost, and liability have slowed the growth of the nuclear power industry Accidents at Chernobyl and Three Mile Island showed that a partial or complete meltdown is possible

Nuclear Power Plants in U.S. cstl-cst.semo.edu/bornstein/BS105/ Energy%20Use%20-%203.ppt

Figure 17-25 Page 369 Reactors 1 Operational Yucca Mountain high-level nuclear waste storage site 1 Decommissioned

Three Mile Island March 29, 1979, a reactor near Harrisburg, PA lost coolant water because of mechanical and human errors and suffered a partial meltdown 50,000 people evacuated & another 50,000 fled area Unknown amounts of radioactive materials released Partial cleanup & damages cost $1.2 billion Released radiation increased cancer rates. www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Chernobyl April 26, 1986, reactor explosion (Ukraine) flung radioactive debris into atmosphere Health ministry reported 3,576 deaths Green Peace estimates32,000 deaths; About 400,000 people were forced to leave their homes ~160,000 sq km (62,00 sq mi) contaminated > Half million people exposed to dangerous levels of radioactivity Cost of incident > $358 billion www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Nuclear Energy Nuclear plants must be decommissioned after 15-40 years New reactor designs are still proposed Experimental breeder nuclear fission reactors have proven too costly to build and operate Attempts to produce electricity by nuclear fusion have been unsuccessful

Use of Nuclear Energy U.S. phasing out Some countries (France, Japan) investing increasingly U.S. currently ~7% of energy nuclear No new U.S. power plants ordered since 1978 40% of 105 commercial nuclear power expected to be retired by 2015 and all by 2030 North Korea is getting new plants from the US France 78% energy nuclear www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Phasing Out Nuclear Power Multi-billion-$$ construction costs High operation costs Frequent malfunctions False assurances and cover–ups Overproduction of energy in some areas Poor management Lack of public acceptance www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

2) Energy Energy & Mineral resources garnero101.asu.edu/glg101/Lectures/L37.ppt