Fossil Fuels

Fossil FuelsChapter 15

Section 15.1 the need for energyForms of energyMechanical energy motion- Also known as Kinetic energy.Chemical energy stored energy (food)- Also known as Potential energy.Nuclear energy nucleus of an atomThermal energy - heat

Law of conservation of energy states that energy cannot be created or destroyed but it can change forms.

Law of conservation of energy

ThermalChemical

MechanicalChemical

Food is a form of fuel that your body uses for energy.Fuel any substance from which energy can be obtained.Fossil Fuels fuels derived from the remains of organisms that lived long agoThey contain a great deal of energy.Also known as an organic fuel.Section 15.2 coalFormed from plant remains that were once living in swamps.The plant matter loses hydrogen and oxygen, leaving behind carbon.Takes over millions of years to form; nonrenewable.4 stages1. Peat - brittle, brown plant material (resembles decaying wood)Contains a lot of water and a low percentage of carbon.Gives off a lot of smoke because high in water.Not a form of coal.

Section 15.2 coal2. Lignite soft, brown coal; composed of 40% carbonHeat and pressure forces the water out of peat, forming lignite.Burns quickly and gives off very little smoke.Located below earths surface and must be mined.First true form of coal!3. Bituminous Coal - soft coal; composed of up to 85% carbonForms deep in the earths crust.Most abundant type mined in the U.S. Burns hotter and with less smoke than peat or ligniteUsed in many power plants to produce the energy needed to heat water into steam that generates electricity.

Section 15.2 coal4. Anthracite Coal - a hard coal; composed of up to 95% carbonMetamorphic rock, shiny, black colorLeast water, fewest impurities, and highest carbon contentBurns the hottest with the least amount of smoke (clean)Least abundant therefore the most expensive form of coal.Most often used to heat homes.

Geology LinkDiamonds are also formed from carbonCoal is formed from plant remains; diamonds are formed from extreme heat and pressure in Earths mantleMany diamond mines are located in South AfricaHardest mineralUsed for cutting and drilling as well as for jewelry

Section 15.3 Petroleum & natural gasPetroleumAlso called crude oil.Liquid fossil fuel thought to be formed from remains of plankton and microscopic protists, plants, and animals living millions of years ago.Over millions of years, the heat and pressure from the ocean floor converted the remains into a syrupy liquid called petroleum.Pressure from overlying rocks forced the petroleum to moved upward through pores of sedimentary rocks. When the petroleum met nonporous rock, it became trapped below the surface.

Petroleum continuedA great deal of pressure can build up in an oil pool trapped below the groundWhen a well is drilled into this pool, the pressure forces the oil to shoot upward, forming a gusherIf there is little or no pressure, oil must be pumped to the surfaceGas and jet fuels, diesel fuel, fuel oil, grease, lubricants, plastics, asphalt, nylon, & polyester come from petroleum One of the worlds most important resourcesNonrenewable

Section 15.3 Petroleum & natural gasNatural gasMixture of mostly gaseous hydrocarbonsMethane, ethane, propane are some types. Forms like petroleumFound trapped above petroleum poolsViewed as a waste or by-product of petroleum drillingWidely used in industryBurns cleaner than other fuelsUsed in stoves, water heaters, and clothes dryersMore energy efficient because it does not have to be converted to electricity to be used.

Section 15.4 Other organic FuelsProblems with fossil fuelsAvailabilityNonrenewableNot located everywherePollutionOil spillsAir pollutionCO2 released into air (greenhouse effect)DangerousNatural gas is extremely combustible; coal miners can die of suffocation by natural gasEnvironmental damageSection 15.4 Other organic FuelsBiomass FuelsA fuel formed from the products of living organismsRenewable!Examples include: wood, garbage, methane, and alcohol

1. WoodIn developing nations where fuels are too expensive, people rely on wood for fuel.Disadvantages Gives off a lot of smoke high in CO2; damages forests.

Biomass Fuels continued2. GarbageComposed largely of organic material (paper, food scraps)2/3 of material in garbage cans be burned.Some U.S. cities are burning garbage to produce electricity.Using it as a biomass fuel would help solve the problem of running out of land fill space.

3. MethaneSwamp gas from decaying plantsDecaying garbage in dumps produces methane.Used the same way as natural gas.

Biomass fuels continued4. AlcoholBioconversion the conversion of organic materials into fuelsSugarcane and corn (plants) can make alcohol through bioconversion.Alcohol is a hydrocarbon in which one of the hydrogen atoms has been replaced with hydroxyl (OH)

Biomass fuels continuedThis ethanol is made by yeast through a process called fermentation Ethanol is a liquid biomass that burns cleanly and is a renewable resource.In Brazil, >2million cars are fueled by ethanolOther cars are fueled by gasohol (90% gasoline + 10% ethanol)Manufacturers are also producing cars that run on alcohol made from sunflower or peanut plants

Environmental threatGlobal WarmingOften used to generate electrical energyFossil FuelsNonrenewableBiomass FuelsRenewableMethane

vs.Track 02New Artist (129)New Title (129), track 22005Rock185822.1