3Crust Temperature: Over 175 degrees Celsius Topmost layer of the Earth Relatively coolMade of rock2 types of crustOceanic (4-7 km thick)Continental (20-40 km thick)
4Mantle Temperature: Over 1250 degrees Celsius Makes up about 80% of the Earth’s volume~ 2900 km thickOuter mantle – rocksInner mantle – “plastic”
5Core Temperature: Over 6000 degrees Celsius Outer core – liquid Pressure from the mantle & crust do not allow the metals in the outer core to become gassesInner core – solidPressure from the mantle and crust do not allow the metals to become liquid
6Plate TectonicsThe Earth’s lithosphere is made up of 7 tectonic platesPlate tectonics – the movement of these lithospheric plates
18Focus = point of earthquake origination Epicenter = point on the Earth’s surface directly above the focus
19Energy from an earthquake Energy is released in the forms of wavesP wave: Primary or longitudinal waves originate from the focus & move quickly through rock. These are the first waves to be recordedS wave: Secondary or transverse waves originate from the focus & moves more slowly through rock.Surface waves: move across the earth’s surface, causes building to collapse
20Earthquake Measurement SeismographRecords data about P, S and surface wavesUsed to locate the epicenter of an earthquakeRichter scaleMeasures energy released at the epicenter of an earthquake (in magnitude)Each step up in magnitude represents a 30-fold increase in energy released!
22VolcanoesVolcanoes result from openings or vents in the Earth’s surfaceMagma reaches the surface through these ventsWhen magma reaches the surface it changes physically and is called lava
23Shield Volcano Formed from fluid lava, rich in iron Shield volcanoes are largeMauna Loa in Hawaii
24Composite Volcano Made of alternating layers of lava, ash and cinders. Magma is rich in silica and thickLarge with steep slopes
25Cinder ConeLarge amounts of gas are trapped in the magma causing violent eruptionsActive for short periods of time
26Minerals & Rocks Minerals: naturally occurring, inorganic substances (inorganic = does not contain Carbon)can be expressed by a chemical formulaQuartz SiO2 (silicon dioxide)Rocks:Composed of minerals
27Types of Rock Igneous Sedimentary Metamorphic Formed when magma or lava cools and hardensMagma forms intrusive igneous rockLava forms extrusive igneous rockSedimentaryFormed when rock particles, plant and animal debris are carried away by water, redeposited, then fused togetherMetamorphicRock particles are fused together by pressure beneath the Earth’s surface
28Determining the age of rocks Two ways to “determine” the age of a rock:Superposition – determine the age based on layers, older rocks are on the bottom, newer ones on topRadioactive dating
30Weathering and Erosion Two types of weatheringPhysicalBreaks rocks into smaller pieces, chemical composition does not changeMay be caused by ice or plantsChemicalChanges the chemical composition of rocksMay be caused by oxidation or acid rain
31Erosion Erosion: the process of loosening and removing sediment Caused by water, glaciers, wind
32Deposition Occurs when loose sediment is laid down Causes river beds to widen and deltas to form.
33Important Elements Oxygen – most abundant element in the Earth’s crust Nitrogen – most abundant element in the atmosphereIron – most abundant element in the core
34Non-renewable Resources Defined:An energy source that cannot be renewed in our lifetimeExamples:OilNatural GasCoalAluminumGoldUranium
36Surface MiningDescription – if resource is <200 ft. from the surface, the topsoil is removed (and saved), explosives are used to break up the rocks and to remove the resource, reclamation followsBenefits – cheap, easy, efficientCosts – tears up the land (temporarily), byproducts produce an acid that can accumulate in rivers and lakes
37Underground Mining Underground Mining Description – digging a shaft down to the resource, using machinery (and people) to tear off and remove the resourceBenefits – can get to resources far undergroundCosts – more expensive, more time-consuming, more dangerous – mining accident in Chile
38Coalformed from ancient peat bogs (swamps) that were under pressure as they were covered.Used for electricity, heat, steel, exports, and industry, may contribute to the “Greenhouse Effect”Four types of coal exist: lignite (soft, used for electricity), bituminous and subbituminous (harder, also used for electricity) and anthracite (hardest, used for heating)50% of all the coal is in the United States, the former Soviet Union and China
39Bituminous (soft coal) Anthracite (hard coal) Increasing heat and carbon contentIncreasing moisture contentPeat (not a coal)Lignite (brown coal)Bituminous (soft coal)Anthracite (hard coal)HeatHeatHeatPressurePressurePressurePartially decayed plant matter in swamps and bogs; low heat contentLow heat content; low sulfur content; limited supplies in most areasExtensively used as a fuel because of its high heat content and large supplies; normally has a high sulfur contentHighly desirable fuel because of its high heat content and low sulfur content; supplies are limited in most areasFigure 16.12Natural capital: stages in coal formation over millions of years. Peat is a soil material made of moist, partially decomposed organic matter. Lignite and bituminous coal are sedimentary rocks, whereas anthracite is a metamorphic rock (Figure 15-8, p. 343). QUESTION: Are there coal deposits near where you live or go to school?Fig , p. 368
40Cooling tower transfers waste heat to atmosphere Coal bunker Turbine GeneratorCooling loopStackPulverizing millCondenserFilterFigure 16.13Science: Coal-burning power plant. Heat produced by burning pulverized coal in a furnace boils water to produce steam that spins a turbine to produce electricity. The steam is cooled, condensed, and returned to the furnace for reuse. A large cooling tower transfers waste heat to the troposphere. The largest coal-burning power plant in the United States in Indiana burns 23 metric tons (25 tons) of coal per minute or three 100-car trainloads of coal per day and produces 50% more electric power than the Hoover Dam. QUESTION: Is there a coal-burning power plant near where you live or go to school?BoilerToxic ash disposalFig , p. 369
41COALCoal reserves in the United States, Russia, and China could last hundreds to over a thousand years.The U.S. has 27% of the world’s proven coal reserves, followed by Russia (17%), and China (13%).In 2005, China and the U.S. accounted for 53% of the global coal consumption.
42Reclamationreturning the rock layer and the topsoil to a surface mine, fertilizing and planting itBenefits – restores land to good conditionCosts – expensive, time-consumingIn the United States, mining companies are required to do this!
43Open-pit MiningMachines dig holes and remove ores, sand, gravel, and stone.Toxic groundwater can accumulate at the bottom.Figure 15-11
44Area Strip MiningEarth movers strips away overburden, and giant shovels removes mineral deposit.Often leaves highly erodible hills of rubble called spoil banks.Figure 15-12
45Contour Strip Mining Used on hilly or mountainous terrain. Unless the land is restored, a wall of dirt is left in front of a highly erodible bank called a highwall.Figure 15-13
46Mountaintop RemovalMachinery removes the tops of mountains to expose coal.The resulting waste rock and dirt are dumped into the streams and valleys below.Figure 15-14
48United States mining Central – diamonds (Arkansas), bituminous coal West – bituminous and subbituminous coal, gold, silver, copperEast – anthracite coal, bituminous coalSouth – some gold (SC), bituminous coalNorth – bituminous coal, some gold (SD, WI)
49Energy from non-renewable resources CogenerationPrimarySecondary
50Fossil Fuels Only about 30% efficient Benefits – Costs – easy to use, currently abundantCosts –a nonrenewable resource, produces pollutants that contribute to acid rain and the greenhouse effectOil- Supplies the most commercial energy in the world today. People in the U.S. use 23 barrels of petroleum per person or 6 billion barrels total each year!!!
51Gases Gasoline Aviation fuel Heating oil Diesel oil Naptha Figure 16.5Science: refining crude oil. Based on their boiling points, components are removed at various levels in a giant distillation column. The most volatile components with the lowest boiling points are removed at the top of the column.Heated crude oilGrease and waxFurnaceAsphaltFig. 16-5, p. 359
52OILEleven OPEC (Organization of Petroleum Exporting Countries) have 78% of the world’s proven oil reserves and most of the world’s unproven reserves.After global production peaks and begins a slow decline, oil prices will rise and could threaten the economies of countries that have not shifted to new energy alternatives.
53Case Study: U.S. Oil Supplies The U.S. – the world’s largest oil user – has only 2.9% of the world’s proven oil reserves.U.S oil production peaked in 1974 (halfway production point).About 60% of U.S oil imports goes through refineries in hurricane-prone regions of the Gulf Coast.
54Heavy Oils from Oil Sand and Oil Shale: Will Sticky Black Gold Save Us? Heavy and tarlike oils from oil sand and oil shale could supplement conventional oil, but there are environmental problems.High sulfur content.Extracting and processing produces:Toxic sludgeUses and contaminates larges volumes of waterRequires large inputs of natural gas which reduces net energy yield.
55Oil ShalesOil shales contain a solid combustible mixture of hydrocarbons called kerogen.Figure 16-9
56Core Case Study: How Long Will the Oil Party Last? We have three options:Look for more oil.Use or waste less oil.Use something else.Figure 16-1
57NATURAL GASNatural gas, consisting mostly of methane, is often found above reservoirs of crude oil.When a natural gas-field is tapped, gasses are liquefied and removed as liquefied petroleum gas (LPG).Coal beds and bubbles of methane trapped in ice crystals deep under the arctic permafrost and beneath deep-ocean sediments are unconventional sources of natural gas.
58NATURAL GASRussia and Iran have almost half of the world’s reserves of conventional gas, and global reserves should last years.Natural gas is versatile and clean-burning fuel, but it releases the greenhouse gases carbon dioxide (when burned) and methane (from leaks) into the troposphere.
61Energy Efficiency – Non-renewable energy sources Coal, Natural Gas, Oil: about 30% efficientNuclear:
62Laws of Thermodynamics 1st law: Conservation of EnergyEnergy cannot be created nor destroyedEnergy can be transferred from one system to another2nd law:Energy transfer must only have one directionEntropy (disorder) increases over time3rd law:Absolute zero is achieved when all kinetic energy stops
63SO….. 1st law of Thermodynamics Explains how we can convert energy from chemical or mechanical energy to usable electric energywindmill animation2nd law of Thermodynamics explains WHY energy efficiency can be so low
65Solar Solar energy is harnessing energy from the sun’s rays Passive Solar – Placing buildings strategically to take advantage of the sun’s heatExample: Log HomesActive Solar – uses solar panels to convert energy into a usable form such as electricity
66Panels of solar cells Solar shingles Single solar cellSolar-cell roof–+Boron enriched siliconRoof optionsJunctionFigure 17.17Solutions: photovoltaic (PV) or solar cells can provide electricity for a house or building using solar-cell roof shingles, as shown in this house in Richmond Surrey, England. Solar-cell roof systems that look like a metal roof are also available. In addition, new thin-film solar cells can be applied to windows and outside walls.Phosphorus enriched siliconPanels of solar cellsSolar shinglesFig , p. 398
67Benefits of Solar:Readily availableRenewableFairly simple systemPollution free energy sourceCan sell back extra energy to the power companyDrawbacks of Solar:High start up cost for active solar energy systemLocation dependent (Seattle would not be a good city for solar energy)
68Core Case Study: The Coming Energy-Efficiency and Renewable-Energy Revolution It is possible to get electricity from solar cells that convert sunlight into electricity.Can be attached like shingles on a roof.Can be applied to window glass as a coating.Can be mounted on racks almost anywhere.
69Core Case Study: The Coming Energy-Efficiency and Renewable-Energy Revolution The heating bill for this energy-efficient passive solar radiation office in Colorado is $50 a year.Figure 17-1
71Passive Solar HeatingPassive solar heating system absorbs and stores heat from the sun directly within a structure without the need for pumps to distribute the heat.Figure 17-13
72Summer sun Warm air Winter sun Direct GainCeiling and north wall heavily insulatedSummer sunHot airWarm airSuper-insulated windowsWinter sunFigure 17.13Solutions: three examples of passive solar design for houses.Cool airEarth tubesFig , p. 396
73Greenhouse, Sunspace, or Attached Solarium Summer cooling ventWarm airInsulated windowsCool airFigure 17.13Solutions: three examples of passive solar design for houses.Fig , p. 396
74Reinforced concrete, carefully waterproofed walls and roof Earth ShelteredReinforced concrete, carefully waterproofed walls and roofTriple-paned or superwindowsEarthFigure 17.13Solutions: three examples of passive solar design for houses.Flagstone floor for heat storageFig , p. 396
75Passive or Active Solar Heating Trade-OffsPassive or Active Solar HeatingAdvantagesDisadvantagesEnergy is freeNeed access to sun 60% of timeNet energy is moderate (active) to high (passive)Sun blocked by other structuresQuick installationNeed heat storage systemNo CO2 emissionsVery low air and water pollutionHigh cost (active)Figure 17.14Trade-offs: advantages and disadvantages of heating a house with passive or active solar energy. QUESTION: Which single advantage and which single disadvantage do you think are the most important?Very low land disturbance (built into roof or window)Active system needs maintenance and repairModerate cost (passive)Active collectors unattractiveFig , p. 396
76Cooling Houses Naturally We can cool houses by:Superinsulating them.Taking advantages of breezes.Shading them.Having light colored or green roofs.Using geothermal cooling.
77WindWind energy is converted into a usable energy form by using wind turbines
78Wind Power Benefits of Wind Power: Readily available Can sell back extra powerPollution free energy sourceDrawbacks of Wind Power:Disrupts migration patternsTurbine farms are not aesthetically pleasingTurbines are expensiveGood for specific locations only
79Hydro Hydro power is mechanical energy derived from water Most hydropower is generated by damming riversUsing waves or ocean currents is being researched as a source of hydropower
83Benefits of Hydropower Readily availableNo pollution producedConstant source of powerDrawbacks of HydropowerDamming rivers disrupts ecosystems, causes sediment to build up and disrupts the natural flow of a river
84Geothermal Geothermal energy uses natural underground heat sources When heat escapes the earth in the form of steam, the steam is used to turn a steam turbine which converts the heat energy into electrical energy
85Benefits of Geothermal: When drilled correctly, little pollution is producedTakes up a relatively small area, does not disrupt the landscapeDrawbacks of Geothermal:Can only be used in a limited capacityVery location specificMay run out of steamMay release hazardous gasses or minerals if drilled improperly
86BiomassBiomass is burning biomass fuel in a specialized burner. Steam generated turns a steam turbine which turns mechanical energy into electrical energy
87Biomass at the Denver Zoo! Trash and animal waste is converted into pelletsThe pellets are put into a gassifier and heated to 400 degrees!When hot enough, a gas is emitted that is converted by micro gas turbines into electrical energyDenver Zoo
88Benefits of BiomassLess waste in landfillsReadily availableDrawbacks of GeothermalNot currently available on a large scale basis
89USING RENEWABLE SOLAR ENERGY TO PROVIDE HEAT AND ELECTRICITY The European Union aims to get 22% of its electricity from renewable energy by 2010.Costa Rica gets 92% of its energy from renewable resources.China aims to get 10% of its total energy from renewable resources by 2020.In 2004, California got about 12% of its electricity from wind and plans to increase this to 50% by 2030.
90Energy Efficiency – renewable energy sources SolarWindHydroBiomassGeothermal
91USING RENEWABLE SOLAR ENERGY TO PROVIDE HEAT AND ELECTRICITY Denmark now gets 20% of its electricity from wind and plans to increase this to 50% by 2030.Brazil gets 20% of its gasoline from sugarcane residue.In 2004, the world’s renewable-energy industries provided 1.7 million jobs.