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Chapter 14:Chapter 14:Energy: Some BasicsEnergy: Some Basics
OverviewOverview Outlook for EnergyOutlook for Energy Energy BasicsEnergy Basics Energy EfficiencyEnergy Efficiency Energy Sources and ConsumptionEnergy Sources and Consumption Energy Conservation, Increased Energy Conservation, Increased
Efficiency and CogenerationEfficiency and Cogeneration Sustainable Energy PolicySustainable Energy Policy
Outlook for EnergyOutlook for Energy Energy Crisis in Greece and RomeEnergy Crisis in Greece and Rome
Greeks and Romans used wood to heat their Greeks and Romans used wood to heat their homeshomes
As local supplies ran out had to bring it in from As local supplies ran out had to bring it in from farther awayfarther away
Eventually both societies learned to build Eventually both societies learned to build houses south facinghouses south facing Allows sun to heat house in winterAllows sun to heat house in winter Sustainable Sustainable Laws protected a person’s right to solar energyLaws protected a person’s right to solar energy
Outlook for EnergyOutlook for Energy Energy situation facing the US today Energy situation facing the US today
is similar to that faced by Greeks and is similar to that faced by Greeks and RomansRomans Wood use peaked in 1880sWood use peaked in 1880s Coal use peaked in 1920Coal use peaked in 1920 Reaching the peak of oil and gas useReaching the peak of oil and gas use
The decisions we make today will The decisions we make today will affect energy use for generationsaffect energy use for generations
Energy BasicsEnergy Basics ForceForce
Exert force by pushing or pulling Exert force by pushing or pulling Strength of force can be measured by Strength of force can be measured by
how much it accelerates an objecthow much it accelerates an object Ex: pushing a car uphillEx: pushing a car uphill
Energy BasicsEnergy Basics Physics terms:Physics terms:
Work - exerting force over a distanceWork - exerting force over a distance Work is the product of a force times a distanceWork is the product of a force times a distance
Energy - ability to do workEnergy - ability to do work When the car is on the hill, it has potential When the car is on the hill, it has potential
energyenergy Energy can be converted from one kind to Energy can be converted from one kind to
anotheranother First law of thermodynamics- total energy First law of thermodynamics- total energy
must be conservedmust be conserved
Conservation of Energy Conservation of Energy IllustrationIllustration
Tire swingTire swing Highest position - all Highest position - all
energy is stored energy is stored potential energypotential energy
Lowest position - all Lowest position - all energy is kinetic energy is kinetic energyenergy
Energy of motionEnergy of motion With each swing With each swing
friction slows the friction slows the swing - heat energyswing - heat energy
Eventually all energy is Eventually all energy is converted to heat and converted to heat and the swing stopsthe swing stops
Energy BasicsEnergy Basics Energy qualityEnergy quality
The ability of the energy to do workThe ability of the energy to do work Higher quality of the energy = more easily Higher quality of the energy = more easily
converted to workconverted to work Lower energy quality = more difficult to Lower energy quality = more difficult to
convert to workconvert to work Second law of thermodynamicsSecond law of thermodynamics
Energy always tends to go from a more Energy always tends to go from a more usable (higher-quality) form to a less usable usable (higher-quality) form to a less usable (lower-quality) form(lower-quality) form
When you use energy, you lower its qualityWhen you use energy, you lower its quality
Energy EfficiencyEnergy Efficiency
Two fundamental types of energy Two fundamental types of energy efficiencies efficiencies Derived from the first and second laws of Derived from the first and second laws of
thermodynamicsthermodynamics First-law efficiencyFirst-law efficiency Second-law efficiencySecond-law efficiency
First-law efficiency First-law efficiency Deals with the amount of energy without any Deals with the amount of energy without any
consideration of the quality or availability of consideration of the quality or availability of the energythe energy
Energy EfficiencyEnergy Efficiency
Second-law efficiency Second-law efficiency Refers to how well matched the energy Refers to how well matched the energy
end use is with the quality of the energy end use is with the quality of the energy sourcesource
Low values indicate where Low values indicate where improvements in energy technology and improvements in energy technology and planning may save significant amounts planning may save significant amounts of high-quality energyof high-quality energy
Energy EfficienciesEnergy Efficiencies Electricity generating plants have Electricity generating plants have
nearly the same first-law and nearly the same first-law and second-law efficienciessecond-law efficiencies Generating plants are examples of heat Generating plants are examples of heat
enginesengines Produces work from heatProduces work from heat Most electricity generated in the world Most electricity generated in the world
comes from heat engines comes from heat engines Use nuclear fuel, coal, gas, or other fuelsUse nuclear fuel, coal, gas, or other fuels
Energy Sources and Energy Sources and ConsumptionConsumption
Industrialized countries:Industrialized countries: Small percentage of the total populationSmall percentage of the total population Large user of total energy produced Large user of total energy produced
Ex: United States Ex: United States Only 5% of the world’s populationOnly 5% of the world’s population Uses ~25% of the total energy Uses ~25% of the total energy
consumedconsumed
Fossil Fuels and Alternative Fossil Fuels and Alternative Energy SourcesEnergy Sources 90% of the energy consumed in the US 90% of the energy consumed in the US
comes from fossil fuelscomes from fossil fuels Petroleum, natural gas, and coalPetroleum, natural gas, and coal They are essentially nonrenewableThey are essentially nonrenewable
Other sources of energyOther sources of energy Alternative energy sources Alternative energy sources
Geothermal, nuclear, hydropower, and solarGeothermal, nuclear, hydropower, and solar Renewable energy sourcesRenewable energy sources
Solar and windSolar and wind Not depleted by consumptionNot depleted by consumption
Energy Consumption in the Energy Consumption in the US TodayUS Today US dependent on the three major US dependent on the three major
fossil fuels fossil fuels CoalCoal Natural gasNatural gas PetroleumPetroleum
From 1950 to late-1970s, energy From 1950 to late-1970s, energy consumption increased consumption increased From 30 exajoules to 80 exajoulesFrom 30 exajoules to 80 exajoules
Energy Consumption in the US Energy Consumption in the US TodayToday Since about 1980, energy consumption Since about 1980, energy consumption
has increased by only about 25 exajouleshas increased by only about 25 exajoules Suggests that policies to improve energy Suggests that policies to improve energy
conservation through efficiency improvements conservation through efficiency improvements have been at least partially successfulhave been at least partially successful
Energy losses are associated with Energy losses are associated with Production of electricity and transportationProduction of electricity and transportation Use of heat enginesUse of heat engines
Energy loss in 2009 was equal to energy Energy loss in 2009 was equal to energy usage in 1965!usage in 1965!
Energy article read
Read article and highlight important topics regarding energy consumption
Summarize article in 10 sentence and be ready to share with a neighbor….
2020
Energy Consumption in the Energy Consumption in the US TodayUS Today Look at the generalized energy flow of the Look at the generalized energy flow of the
US for a particular year (next few slides)US for a particular year (next few slides) We imported considerably more oil than we We imported considerably more oil than we
producedproduced Consumption distributed in three sectors:Consumption distributed in three sectors:
Residential/commercialResidential/commercial IndustrialIndustrial TransportationTransportation
We remain dangerously vulnerable to We remain dangerously vulnerable to changing world conditions affecting the changing world conditions affecting the production of oilproduction of oil
Energy crisis poster
Create and Develop an informational poster diagramming the energy crisis in the united states be sure to include some ideas from the article and your own research.
Make sure it attracts the eyes and makes it known the trouble we are having with energy.
2323
Energy Conservation, Increased Energy Conservation, Increased Efficiency and CogenerationEfficiency and Cogeneration Conservation of energyConservation of energy
Using less energyUsing less energy Adjusting our energy needs and uses to Adjusting our energy needs and uses to
minimize the amount of high-quality energy minimize the amount of high-quality energy necessary for a given tasknecessary for a given task
Increased energy efficiency Increased energy efficiency Designing equipment to yield more energy Designing equipment to yield more energy
output from a given amount of input energy output from a given amount of input energy (first-law efficiency) (first-law efficiency)
Better matches between energy source and Better matches between energy source and end use (second-law efficiency)end use (second-law efficiency)
Energy Conservation, Energy Conservation, Increased Efficiency and Increased Efficiency and CogenerationCogeneration Cogeneration Cogeneration
Processes designed to capture and use Processes designed to capture and use waste heat (no thermal pollution)waste heat (no thermal pollution)
Captured waste heat increases overall Captured waste heat increases overall efficiency of a typical power plant from 33% efficiency of a typical power plant from 33% to 75%to 75%
Could provided ~ 10% of the power Could provided ~ 10% of the power capacity of the UScapacity of the US
Building DesignBuilding Design Many ways to increase energy Many ways to increase energy
efficiency and conservation in efficiency and conservation in residential buildingsresidential buildings Design and construct homes that Design and construct homes that
minimize the energy consumptionminimize the energy consumption Design buildings to take advantage of Design buildings to take advantage of
passive solar potentialpassive solar potential For older homes: insulation, caulking, For older homes: insulation, caulking,
weather stripping, installation of weather stripping, installation of window coverings, storm windows, window coverings, storm windows, and regular maintenanceand regular maintenance
Industrial EnergyIndustrial Energy
Industrial production of goods Industrial production of goods continues to grow significantlycontinues to grow significantly US industry consumes ~1/3 of the US industry consumes ~1/3 of the
energy producedenergy produced More industries are using co-generation More industries are using co-generation
and more energy-efficient machineryand more energy-efficient machinery
Automobile designAutomobile design Early 1970s, Early 1970s,
Ave US automobile = 14 mpgAve US automobile = 14 mpg By 1996By 1996
Ave = 28 mpg (highway)Ave = 28 mpg (highway) 1996–19991996–1999
Fuel consumption rates did not improve muchFuel consumption rates did not improve much 2004 2004
Many vehicles sold were SUVs and light trucks Many vehicles sold were SUVs and light trucks with fuel consumption of 10–20 mpg with fuel consumption of 10–20 mpg
SUVs fell into loophole in fuel efficiency SUVs fell into loophole in fuel efficiency regulationsregulations
SUVs purchases in 2006SUVs purchases in 2006
Automobile designAutomobile design Today, some hybrid (gasoline-electric) Today, some hybrid (gasoline-electric)
vehicles exceeds 90 mpg on the highway vehicles exceeds 90 mpg on the highway and 60 mpg in the cityand 60 mpg in the city
Improvement has several causes: Improvement has several causes: Increased efficiency and resulting conservation Increased efficiency and resulting conservation
of fuelof fuel Cars that are smaller; engines constructed of Cars that are smaller; engines constructed of
lighter materialslighter materials Combo of a fuel-burning engine and an electric Combo of a fuel-burning engine and an electric
motormotor Plug-in hybridsPlug-in hybrids
Values, Choices, and Energy Values, Choices, and Energy ConservationConservation Ways of modifying behavior to conserve Ways of modifying behavior to conserve
energy include the following:energy include the following: bike, walk, or take a bus or train to workbike, walk, or take a bus or train to work Carpools Carpools Hybrid cars (gasoline–electric)Hybrid cars (gasoline–electric) Turn off lights when leaving roomsTurn off lights when leaving rooms Take shorter showersTake shorter showers Turn down the thermostatTurn down the thermostat Use energy-efficient compact florescent Use energy-efficient compact florescent
lightbulbslightbulbs Purchase energy-efficient appliancesPurchase energy-efficient appliances
Values, Choices, and Energy Values, Choices, and Energy ConservationConservation
Seal drafts in buildingsSeal drafts in buildings Better insulate your homeBetter insulate your home Wash clothes in cold water whenever Wash clothes in cold water whenever
possiblepossible Purchase local foods to reduce energy in Purchase local foods to reduce energy in
transporttransport Use power strips and turning them off Use power strips and turning them off
when not in usewhen not in use
Energy PolicyEnergy Policy Business-As-Usual Approach (our Business-As-Usual Approach (our
current approach)current approach) PhilosophyPhilosophy
Find more fossil fuelFind more fossil fuel Build larger power plantsBuild larger power plants Use energy as freely as we always haveUse energy as freely as we always have
Requires no new thinkingRequires no new thinking Requires no realignment of political, Requires no realignment of political,
economic or social conditionseconomic or social conditions Does not anticipate reductions in oil Does not anticipate reductions in oil
productionproduction
Energy for TomorrowEnergy for Tomorrow Existing patterns of energy use will Existing patterns of energy use will
change based onchange based on Changes in population densitiesChanges in population densities Intensive conservation measuresIntensive conservation measures
2050 energy consumption of US may be 2050 energy consumption of US may be 160 exajoules160 exajoules What will the energy source be?What will the energy source be? Will we follow business-as-usual or turn Will we follow business-as-usual or turn
to alternative sources?to alternative sources?
Energy Policy for the 21Energy Policy for the 21stst centurycentury Promote conventional energy sourcesPromote conventional energy sources
But reduce our reliance on foreign sourcesBut reduce our reliance on foreign sources Encourage alternative energyEncourage alternative energy
Wind, solar, geothermal, hydrogen and biofuelsWind, solar, geothermal, hydrogen and biofuels Provide for energy infrastructureProvide for energy infrastructure Promote conservation measuresPromote conservation measures
Higher product efficiency standards, less waste Higher product efficiency standards, less waste energy, tax creditsenergy, tax credits
Evaluate the pros and cons of nuclear Evaluate the pros and cons of nuclear powerpower
Promote research into all energy sourcesPromote research into all energy sources
Integrated, Sustainable Integrated, Sustainable Energy ManagementEnergy Management No single energy source can provide No single energy source can provide
all the energy required. all the energy required. Range of options that vary from Range of options that vary from
region to region will have to be region to region will have to be employedemployed Fossil fuelsFossil fuels Alternative, renewable sourcesAlternative, renewable sources
Integrated, Sustainable Integrated, Sustainable Energy ManagementEnergy Management Basic goal is to move toward sustainable Basic goal is to move toward sustainable
energy developmentenergy development Implemented at the local levelImplemented at the local level
Would have the following characteristics:Would have the following characteristics: Provide reliable sources of energyProvide reliable sources of energy Not cause destruction or serious harm to our Not cause destruction or serious harm to our
global, regional, or local environmentsglobal, regional, or local environments Help ensure that future generations inherit a Help ensure that future generations inherit a
quality environment with a fair share of the quality environment with a fair share of the Earth’s resourcesEarth’s resources
Integrated, Sustainable Integrated, Sustainable Energy ManagementEnergy Management A good plan should do the following:A good plan should do the following:
Provide for sustainable energy Provide for sustainable energy developmentdevelopment
Provide for aggressive energy efficiency Provide for aggressive energy efficiency and conservationand conservation
Provide for the diversity and integration Provide for the diversity and integration of energy sourcesof energy sources
Provide for a balance between economic Provide for a balance between economic health and environmental qualityhealth and environmental quality
Use second-law efficiencies as an Use second-law efficiencies as an energy policy toolenergy policy tool
Integrated, Sustainable Integrated, Sustainable Energy ManagementEnergy Management The global pattern of ever-increasing The global pattern of ever-increasing
energy consumption led by the US energy consumption led by the US cannot be sustained w/o a new cannot be sustained w/o a new energy paradigmenergy paradigm Includes changes in human values Includes changes in human values
rather than a breakthrough in rather than a breakthrough in technologytechnology
Examples:Examples: Choosing to own fuel-efficient automobiles Choosing to own fuel-efficient automobiles Living in more energy-efficient homesLiving in more energy-efficient homes