Energy Resources. Energy What is Energy ? Many of us would answer…. electricity orgasoline or maybe nuclear power

EnergyEnergyResourcesResources

EnergyEnergy What is Energy ?What is Energy ?

Many of us would answer….Many of us would answer….

electricityelectricity oror gasolinegasoline

or maybeor maybe nuclear powernuclear power

EnergyEnergy What is Energy ?What is Energy ?

For many people in LDCsFor many people in LDCs

energy is…energy is… fuel woodfuel wood

EnergyEnergy fuel woodfuel wood

• In LDCs used for In LDCs used for cooking and heatingcooking and heating


• The “other” energy crisisThe “other” energy crisis

• A major problem in LDCsA major problem in LDCs

fuel woodfuel wood The “other” energy crisisThe “other” energy crisis

• As population growsAs population grows

the need for fuel the need for fuel wood energy growswood energy grows

fuel woodfuel wood The “other”The “other” energy crisisenergy crisis

treestrees

shrubs & bushesshrubs & bushes

grassesgrasses

crop residuescrop residues

dried dungdried dung

treestrees

shrubs & bushesshrubs & bushes

grassesgrasses

crop residuescrop residues

dried dungdried dung

The demand for The demand for fuel wood is fuel wood is resulting inresulting in

soil erosion,soil erosion,

soil nutrient soil nutrient depletion, anddepletion, and

landland degradationdegradation


• The “other” energy crisisThe “other” energy crisis

• A major problem in LDCsA major problem in LDCs

In MDCs, abundant In MDCs, abundant energy is vital to societyenergy is vital to society

EnergyEnergy

Modern industrial Modern industrial culture is energy intensiveculture is energy intensive

Human cultural evolutionHuman cultural evolution

has been accompanied byhas been accompanied by

Energy & CultureEnergy & Culture

• Increasingly powerful energy sourcesIncreasingly powerful energy sources

• Increased per capita energy utilizationIncreased per capita energy utilization

Hunter-gatherer societyHunter-gatherer society

Energy & CultureEnergy & Culture

• human muscle power & firehuman muscle power & fire

Agricultural societyAgricultural society• domesticated draft animalsdomesticated draft animals• wind & water powerwind & water power

Energy & CultureEnergy & Culture Early industrial societyEarly industrial society

• coal energy – fossil fuelcoal energy – fossil fuel

• steam enginessteam engines

Energy & CultureEnergy & Culture Modern industrial societyModern industrial society• oil & natural gas energy – fossil fuelsoil & natural gas energy – fossil fuels

• internal combustion enginesinternal combustion engines

• electrical energyelectrical energy

• nuclear energynuclear energy

Time Time PeriodPeriod

U.S. Energy SourcesU.S. Energy SourcesPrimary Energy Primary Energy

SourceSource

Pre - 1850Pre - 1850 Fuel WoodFuel Wood

From 1850 to 1900 the use of fire wood From 1850 to 1900 the use of fire wood decreased as the use of coal increaseddecreased as the use of coal increased


U.S. Energy SourcesU.S. Energy Sources

Primary Energy Primary Energy SourceSource

1900 - 19501900 - 1950 CoalCoal

The use of oil grew during the The use of oil grew during the first half of the 20first half of the 20thth century century


U.S. Energy SourcesU.S. Energy SourcesPrimary Energy Primary Energy

SourceSource

1950 - present1950 - present OilOil

During the second half of the 20During the second half of the 20 thth century, oil use surpassed coal usecentury, oil use surpassed coal use

The United States has The United States has about 6% of world populationabout 6% of world population

U.S. Energy UseU.S. Energy Use

but we use about one-third but we use about one-third of the world’s energyof the world’s energy

High energy use does contribute High energy use does contribute to a high standard of livingto a high standard of living


but much of our energy is but much of our energy is used wastefullyused wastefully

The U.S. is an energy The U.S. is an energy GLUTTONGLUTTON

We can maintain our We can maintain our standard of livingstandard of living


but reduce our energy use throughbut reduce our energy use through

efficiency & conservationefficiency & conservation

Energy efficiency Energy efficiency & conservation& conservation

Doing the same work, Doing the same work, but using less energybut using less energy

Our best energy “source”Our best energy “source”

Reduces use of fossil fuelsReduces use of fossil fuels


Reduces pollutionReduces pollution

Reduces release of Reduces release of greenhouse gasesgreenhouse gases

Prolongs supplies of fossil fuelsProlongs supplies of fossil fuels

Reduces need for new Reduces need for new energy plantsenergy plants


Allows more time for Allows more time for development of alternative energiesdevelopment of alternative energies


Saves moneySaves money

Improves our balance of tradeImproves our balance of trade

Reduces reliance on Reduces reliance on imported oilimported oil

1973 OPEC Oil Embargo1973 OPEC Oil Embargo

U. S. Reliance On U. S. Reliance On Imported OilImported Oil

OOPPEECC

rganization ofrganization ofetroleumetroleumxportingxportingountriesountries

Reduced Reduced availability availability of crude oilof crude oil

Sharp increase in crude oil pricesSharp increase in crude oil prices



gasoline,gasoline,

home heating oilhome heating oildiesel, anddiesel, and Prices forPrices for

sharply increasedsharply increased

Rapid increases in costs of Rapid increases in costs of consumer productsconsumer products


Rapid increase in overall Rapid increase in overall cost of livingcost of living

Period of double-digit inflationPeriod of double-digit inflation

Gasoline shortagesGasoline shortages


Long lines at gasoline stationsLong lines at gasoline stations

Growing popularity of Growing popularity of smaller, fuel-efficient autossmaller, fuel-efficient autos

National concern for energy National concern for energy conservation and energy conservation and energy

independenceindependence


President Carter called President Carter called

the the energy crisisenergy crisis “the “the moral equivalent of war”moral equivalent of war”

The Carter administration The Carter administration increased federal support for increased federal support for alternative energy research alternative energy research

and developmentand development


Unfortunately, federal support for Unfortunately, federal support for alternative energy research and development alternative energy research and development

declined after the Carter administrationdeclined after the Carter administration


The U.S. is now more dependent on The U.S. is now more dependent on imported oil than it was in 1973imported oil than it was in 1973

EnergyEnergyUse of Fossil FuelsUse of Fossil Fuels

CoalCoal

PetroleumPetroleum

Natural GasNatural Gas

Use of Fossil FuelsUse of Fossil Fuels

EnergyEnergy

Currently, our largest Currently, our largest energy sourceenergy source

Large-scale use for only Large-scale use for only about 200 yearsabout 200 years


EnergyEnergy

Large-scale use will Large-scale use will decline in the futuredecline in the future

• Decreasing suppliesDecreasing supplies


EnergyEnergy


• Increasing costsIncreasing costs


EnergyEnergy


• Adverse environmental Adverse environmental impactsimpacts

““From the perspective of a From the perspective of a 10,000 year time span, human 10,000 year time span, human utilization of fossil fuels will utilization of fossil fuels will seem like a brief, toxic fire seem like a brief, toxic fire

aboard a spaceship”aboard a spaceship”


TimeTime

PresentPresent- 5000- 5000 yearsyears

+ 5000+ 5000 yearsyears


““From the perspective of a From the perspective of a 10,000 year time span, human 10,000 year time span, human utilization of fossil fuels will utilization of fossil fuels will seem like a brief, toxic fire seem like a brief, toxic fire

aboard a spaceship”aboard a spaceship”


Fossil fuels are a Fossil fuels are a nonrenewable resourcenonrenewable resource


Nonrenewable – no more of Nonrenewable – no more of the resource can be obtained the resource can be obtained within a useful time framewithin a useful time frame

Fossil fuels are a Fossil fuels are a nonrenewable resourcenonrenewable resource


Geologic formation occurred Geologic formation occurred over millions of yearsover millions of years

Reliance on fossil fuels Reliance on fossil fuels is non-sustainableis non-sustainable


Nonrenewable, finite supplyNonrenewable, finite supply

Exhaustion of supply willExhaustion of supply will deprive future generationsdeprive future generations



Exhaustion of supply willExhaustion of supply will deprive future generationsdeprive future generations

• Energy resourceEnergy resource

• Synthetic baseSynthetic base • LubricantsLubricants



Pollution from use mayPollution from use may affect future generationsaffect future generations

• Global Climate ChangeGlobal Climate Change

• Acid PrecipitationAcid Precipitation • Chemical PollutionChemical Pollution



To work toward a sustainable To work toward a sustainable society, we must make the transition society, we must make the transition

to renewable energy sourcesto renewable energy sources

United States Energy SourcesUnited States Energy Sources


The U.S. is heavily dependent The U.S. is heavily dependent on fossil fuelson fossil fuels

Approximately 85% of U.S. energyApproximately 85% of U.S. energy



Petroleum or oil is the largest Petroleum or oil is the largest single source of U.S. energysingle source of U.S. energy

Approximately 40% of U.S. energyApproximately 40% of U.S. energy



- - Approximately 20% Approximately 20% of U.S. energyof U.S. energy

- - Approximately 25% Approximately 25% of U.S. energyof U.S. energy

Natural GasNatural Gas

CoalCoal



Approximately 15% of U.S. Approximately 15% of U.S. energy comes from all other sourcesenergy comes from all other sources

• nuclearnuclear • hydrohydro • solarsolar

• windwind • geothermalgeothermal • otherother



Oil 40%Oil 40%

Natural Natural Gas 25%Gas 25%

Coal 20%Coal 20%

Non Fossil Non Fossil Fuel 15%Fuel 15%

Total Reserves – the amount left to Total Reserves – the amount left to be recoveredbe recovered


Known Reserves Known Reserves – have already – have already been found and quantity estimatedbeen found and quantity estimated

Suspected Reserves Suspected Reserves – thought to exist, – thought to exist, but not yet found, quantity uncertainbut not yet found, quantity uncertain

Use of Fossil FuelsUse of Fossil Fuels Suspected Reserves Suspected Reserves – thought to exist, – thought to exist,

but not yet found, quantity uncertainbut not yet found, quantity uncertain

All the “easy” reserves have been foundAll the “easy” reserves have been found

Suspected reserves will be in remote Suspected reserves will be in remote locations and will be difficult and locations and will be difficult and

expensive to recoverexpensive to recover

How long will fossil How long will fossil fuel reserves last ?fuel reserves last ?


Uncertainties in estimates due toUncertainties in estimates due to

• unknown quantities of suspected reservesunknown quantities of suspected reserves

• will rate of use increase or decreasewill rate of use increase or decrease



Petroleum – the smallest reservesPetroleum – the smallest reserves

• at current rate of use, reserves may lastat current rate of use, reserves may last

40 – 50 years40 – 50 years



Petroleum – the smallest reservesPetroleum – the smallest reserves

• yet the one we use the mostyet the one we use the most

• most urgent need to find a replacementmost urgent need to find a replacement



Natural Gas – Natural Gas – larger reserves than oillarger reserves than oil


60 – 80 years60 – 80 years



Natural Gas – Natural Gas – larger reserves than oillarger reserves than oil

• the “cleanest” fossil fuelthe “cleanest” fossil fuel

• likely that rate of use will increaselikely that rate of use will increase



Coal – Coal – the largest reservesthe largest reserves


200 – 300 years200 – 300 years



Coal – Coal – the largest reservesthe largest reserves

• the “dirtiest” of the fossil fuelsthe “dirtiest” of the fossil fuels

• undesirable to burn it allundesirable to burn it all

Reserves are limitedReserves are limited


• particularly petroleumparticularly petroleum

Use has adverse effectsUse has adverse effects• on humanson humans• on environmenton environment

What are the “costs”What are the “costs”

of fossil fuel use ?of fossil fuel use ?


Costs in a broad senseCosts in a broad sense• includes more than just dollarsincludes more than just dollars

• includes negative effects on includes negative effects on humans and environmenthumans and environment




Human costs may include Human costs may include death and illnessdeath and illness

• difficult to assign a dollar valuedifficult to assign a dollar value




Environmental costs may include Environmental costs may include ecosystem alteration and degradationecosystem alteration and degradation

• difficult to assign a dollar valuedifficult to assign a dollar value




Externalization of CostsExternalization of Costs• someone other than direct producer someone other than direct producer

or direct consumer bears the costsor direct consumer bears the costs




Externalization of CostsExternalization of Costs• the “costs” of fossil fuel use are the “costs” of fossil fuel use are often borne by society as a wholeoften borne by society as a whole

Stages of ExploitationStages of Exploitation


• ExplorationExploration• ExtractionExtraction• ProcessingProcessing

• TransportationTransportation

• End UseEnd Use

End UseEnd Use

Costs of Fossil FuelsCosts of Fossil Fuels

the most significant the most significant human impactshuman impacts

the most significant the most significant environmental impactsenvironmental impacts

Costs of Fossil FuelsCosts of Fossil FuelsEnd UseEnd Use

Global Climate ChangeGlobal Climate Change• fossil fuel combustion releases fossil fuel combustion releases

COCO22 into the atmosphere into the atmosphere

• atmospheric COatmospheric CO22 traps heat in the traps heat in the

atmosphere – global warmingatmosphere – global warming


Global Climate ChangeGlobal Climate Change• the most serious and important threat the most serious and important threat

from our reliance on fossil fuelsfrom our reliance on fossil fuels

• potential major impacts on life on Earthpotential major impacts on life on Earth


Global Climate ChangeGlobal Climate Change

• We will consider this We will consider this important topic in greater detail important topic in greater detail

later in the semesterlater in the semester


Acid PrecipitationAcid Precipitation• Combustion reactions Combustion reactions

release nitrogen oxides (NOx)release nitrogen oxides (NOx)

• Combustion of high sulfur fuels Combustion of high sulfur fuels releases sulfur oxides (SOx)releases sulfur oxides (SOx)


Acid PrecipitationAcid Precipitation• NOx react with atmospheric HNOx react with atmospheric H22O O

to form HNOto form HNO33 – nitric acid – nitric acid

• SOx react with atmospheric HSOx react with atmospheric H22O O

to form Hto form H22SOSO44 – sulfuric acid – sulfuric acid


Acid PrecipitationAcid Precipitation• Adverse effects on forests, Adverse effects on forests,

aquatic ecosystems, structures, aquatic ecosystems, structures, human healthhuman health


Acid PrecipitationAcid Precipitation

• We will consider this topic in We will consider this topic in greater detail later in the semestergreater detail later in the semester


Chemical PollutionChemical Pollution• Combustion of fossil Combustion of fossil fuels results in a variety fuels results in a variety of chemical pollutantsof chemical pollutants


Chemical PollutionChemical Pollution• carbon monoxide (CO)carbon monoxide (CO)

• heavy metalsheavy metals

• radionuclidesradionuclides


Chemical PollutionChemical Pollution• hydrocarbonshydrocarbons

• particulatesparticulates

• ozoneozone


Chemical PollutionChemical Pollution• polycyclic aromatic polycyclic aromatic hydrocarbons (PAHs)hydrocarbons (PAHs)

• peroxyacyl nitrates (PANs)peroxyacyl nitrates (PANs)


Chemical PollutionChemical Pollution• pollutant release has pollutant release has

adverse effects on human adverse effects on human and environmental healthand environmental health


Chemical PollutionChemical Pollution

• We will consider this topic in We will consider this topic in greater detail later in the semestergreater detail later in the semester

Costs of Fossil FuelsCosts of Fossil Fuels

There are enormous human There are enormous human and environmental “costs” and environmental “costs”

associated with continued use associated with continued use of fossil fuelsof fossil fuels

What alternatives are What alternatives are there to the fossil fuels ?there to the fossil fuels ?

Energy AlternativesEnergy Alternatives

• Nuclear PowerNuclear Power

• Renewable EnergiesRenewable Energies

Nuclear Nuclear FissionFission

Nuclear PowerNuclear Power

Nuclear FusionNuclear Fusion

• currently workingcurrently working

• still experimentalstill experimental

• energy from chain reaction of a heavy, energy from chain reaction of a heavy, radioactive elementradioactive element

• energy from combining light energy from combining light elements to form a heavier elementelements to form a heavier element

Nuclear FissionNuclear Fission Heat is Heat is

released from the released from the chain reaction of a chain reaction of a

fissionable fissionable radioactive radioactive

isotopeisotope UU235235 is is typical fueltypical fuel

Heat produces steam to spin a turbine Heat produces steam to spin a turbine and generator to produce electricityand generator to produce electricity

Nuclear FissionNuclear Fission

The radioactive The radioactive fuel is contained in fuel is contained in

the reactor corethe reactor core


Control rods Control rods regulate the rate of regulate the rate of the chain reactionthe chain reaction

Control rods absorb neutrons to Control rods absorb neutrons to regulate the chain reactionregulate the chain reaction


Chernobyl – workers improperly Chernobyl – workers improperly withdrew the control rods leading to withdrew the control rods leading to

a run away chain reactiona run away chain reaction


Chernobyl – the run away chain Chernobyl – the run away chain reaction lead to core meltdown and a reaction lead to core meltdown and a

steam explosionsteam explosion

U.S. reactors are housed in U.S. reactors are housed in containment structurescontainment structures


Chernobyl – the reactor did not Chernobyl – the reactor did not have a containment structurehave a containment structure


Chernobyl – doubtful that a Chernobyl – doubtful that a containment structure could have containment structure could have

withstood the steam explosionwithstood the steam explosion

What are the What are the pros and cons of pros and cons of nuclear fission ?nuclear fission ?


Nuclear Nuclear power has power has

some some advantages advantages over fossil over fossil

fuelsfuels


PROS PROS relative to fossil fuelsrelative to fossil fuels


• No greenhouse gas emissionsNo greenhouse gas emissions

• No acid rain emissionsNo acid rain emissions

• No chemical pollution emissionsNo chemical pollution emissions

• No strip miningNo strip mining

• No acid mine drainageNo acid mine drainage

Nuclear FissionNuclear Fission additionaladditional PROS PROS

• A currently working technologyA currently working technology

• Very high energy densityVery high energy density

• Overall good safety recordOverall good safety record

What are some of the What are some of the CONS or negative CONS or negative aspects of nuclear aspects of nuclear

fission ?fission ?


CONSCONS• Risk of accidents -- ChernobylRisk of accidents -- Chernobyl


• Nonrenewable energy sourceNonrenewable energy source

• Limited amount of fissionable Limited amount of fissionable isotopesisotopes

Not all radioactive isotopes are Not all radioactive isotopes are fissionable – will undergo chain reactionfissionable – will undergo chain reaction


UU238238 – the abundant isotope of uranium – the abundant isotope of uranium is not fissionableis not fissionable

UU235235 – is fissionable, but is a relatively – is fissionable, but is a relatively rare isotope of uraniumrare isotope of uranium

Breeder Reactors could expand Breeder Reactors could expand supply of fissionable materialsupply of fissionable material


Breeder Reactors convert UBreeder Reactors convert U238238 to Pu to Pu239239

The U.S. closed its experimental The U.S. closed its experimental breeder reactor at Clinch River, TNbreeder reactor at Clinch River, TN

CONSCONS


• Potential proliferation of nuclear weaponsPotential proliferation of nuclear weapons

• Concern over possible sabotageConcern over possible sabotage

• Decommissioning old nuclear plantsDecommissioning old nuclear plants

• Disposal of high-level nuclear wastesDisposal of high-level nuclear wastes

Nuclear FissionNuclear Fission What to do with high-level What to do with high-level

nuclear wastes ?nuclear wastes ?

Some isotopes will remain Some isotopes will remain dangerously radioactive for dangerously radioactive for

thousands of yearsthousands of years

The U.S. repository for high-level The U.S. repository for high-level nuclear wastes is under construction at nuclear wastes is under construction at

Yucca Mountain, NVYucca Mountain, NV


The wastes will be buried deep The wastes will be buried deep undergroundunderground

The Yucca Mountain project The Yucca Mountain project is controversialis controversial


Until Yucca Mountain is Until Yucca Mountain is ready, nuclear plants are storing ready, nuclear plants are storing

their wastes on sitetheir wastes on site

CONSCONS Nuclear FissionNuclear Fission

High construction costs and long High construction costs and long construction timeconstruction time

Low public acceptance & Low public acceptance & supportsupport

Lack of private insuranceLack of private insurance

Health effects on uranium minersHealth effects on uranium miners

Point to PonderPoint to Ponder


How do you personally feel about How do you personally feel about nuclear power in the U.S. ?nuclear power in the U.S. ?

• increase a lotincrease a lot

• increase a littleincrease a little

• stay about the samestay about the same

• decrease a littledecrease a little

• decrease a lotdecrease a lot

Energy from combining light Energy from combining light elements to form a heavier elementelements to form a heavier element

• Still an experimental technologyStill an experimental technology

• Energy of sun and starsEnergy of sun and stars

• Much more energy than nuclear fissionMuch more energy than nuclear fission


Nuclear FusionNuclear Fusion Energy of the solar furnaceEnergy of the solar furnace

• The sun can fuse hydrogen The sun can fuse hydrogen atoms together to form ironatoms together to form iron

• Goal of fusion energy on Earth is to Goal of fusion energy on Earth is to fuse hydrogen atoms together to form fuse hydrogen atoms together to form

helium or lithiumhelium or lithium


Challenges to DevelopmentChallenges to Development


• High ignition temperatureHigh ignition temperature

• Confining the reactionConfining the reaction



• High ignition temperatureHigh ignition temperature

Multiple powerful lasers focused on a Multiple powerful lasers focused on a single point in space bring frozen single point in space bring frozen

deuterium pellet to ignition temperaturedeuterium pellet to ignition temperature



• Confining the reactionConfining the reaction

““magnetic bottle”magnetic bottle”

powerful electromagnets confine powerful electromagnets confine reaction in a magnetic fieldreaction in a magnetic field

Still an experimental technologyStill an experimental technology


Controlled fusion reactions Controlled fusion reactions have been achievedhave been achieved

However, the “break-even” However, the “break-even” point has not yet been reachedpoint has not yet been reached

the “break-even” pointthe “break-even” point


• Energy output equals Energy output equals energy inputenergy input

• Energy input – ignition and Energy input – ignition and confinement of reactionconfinement of reaction

the “break-even” pointthe “break-even” point


Energy outputEnergy output ____________________________Energy inputEnergy input == 1.001.00

Potential ProsPotential Pros


• Enormous amounts of energyEnormous amounts of energy

• Deuterium isotope of hydrogen Deuterium isotope of hydrogen is abundant in seawateris abundant in seawater

• No radioactive wastesNo radioactive wastes

ConsCons


• Not a currently working Not a currently working technologytechnology

• Timetable for commercial Timetable for commercial development remains uncertaindevelopment remains uncertain

RenewableRenewableEnergyEnergySourcesSources

No single renewable energy No single renewable energy source will satisfy all energy needssource will satisfy all energy needs

Renewable Energy SourcesRenewable Energy Sources

However, combinations of different However, combinations of different renewable energies can meet most, if renewable energies can meet most, if

not all, of our energy needsnot all, of our energy needs

The exact combination of The exact combination of renewable energies will depend renewable energies will depend upon geographic location and upon geographic location and

the energy applicationthe energy application


Most renewable energy Most renewable energy technologies are sufficiently technologies are sufficiently

developed for large scale applicationdeveloped for large scale application


TODAYTODAY We need to hasten the transition We need to hasten the transition away from fossil fuels and toward away from fossil fuels and toward

renewable energyrenewable energy

Many Pros in commonMany Pros in common


• Renewable – supply will not run outRenewable – supply will not run out

• Low pollution – including COLow pollution – including CO22

• Prolong supply of fossil fuelsProlong supply of fossil fuels

• Compatible with a sustainable societyCompatible with a sustainable society

There are many choices There are many choices available on the renewable energy available on the renewable energy

“menu”“menu”


There are so many choices available that some less promising

technologies will not be widely used for lack of need

Renewable Energy SourcesRenewable Energy Sources Direct SolarDirect Solar

• Passive solarPassive solar• Active solarActive solar• PhotovoltaicsPhotovoltaics• Artificial Artificial PhotosynthesisPhotosynthesis

HydrogenHydrogen

Indirect SolarIndirect Solar• WindWind• HydropowerHydropower• BiomassBiomass• OTECOTEC

TidalTidal GeothermalGeothermal


Solar EnergySolar Energy• Primary energy source for essentially Primary energy source for essentially

all natural ecosystems on earthall natural ecosystems on earth

• Why not the primary energy Why not the primary energy source for human societies ?source for human societies ?


Solar EnergySolar Energy• Direct Solar – directly uses Direct Solar – directly uses

electromagnetic energy of sunlightelectromagnetic energy of sunlight

• Indirect Solar – uses the stored Indirect Solar – uses the stored thermal, kinetic, or chemical thermal, kinetic, or chemical

energy from sunlightenergy from sunlight

Direct SolarDirect Solar

Solar EnergySolar Energy

• Passive solarPassive solar• Active solarActive solar• PhotovoltaicsPhotovoltaics

• Artificial PhotosynthesisArtificial Photosynthesis

Solar EnergySolar Energy Passive solarPassive solar

• Nothing moves – no pumps or Nothing moves – no pumps or working fluidworking fluid

• Relies primarily on architectural Relies primarily on architectural design and constructiondesign and construction


• Archeological evidence suggest Archeological evidence suggest use in ancient buildingsuse in ancient buildings

• Primary value is in lighting and space Primary value is in lighting and space heating and cooling of buildingsheating and cooling of buildings


• Tremendous energy expenditures in Tremendous energy expenditures in lighting and space heating and cooling lighting and space heating and cooling

of buildingsof buildings

can be reduced through can be reduced through passive solar designspassive solar designs

Simple architectural design, such asSimple architectural design, such as

Passive solarPassive solar

• placement of windowsplacement of windows

• placement of overhangsplacement of overhangs

and and

can reduce energy required for can reduce energy required for heating and cooling buildingsheating and cooling buildings

Passive solarPassive solar

winter sunwinter sun summer sunsummer sun

Passive solarPassive solar Simple architectural design, such asSimple architectural design, such as

• Greenhouse Greenhouse or thermal or thermal storage by storage by water or water or masonrymasonry



• Passive solarPassive solar

• Active solarActive solar• PhotovoltaicsPhotovoltaics


Solar EnergySolar Energy Active SolarActive Solar

• A working fluid, usually water, A working fluid, usually water, absorbs heat from sunlight and is absorbs heat from sunlight and is

moved by pumpsmoved by pumps

Solar EnergySolar Energy Active SolarActive Solar

• Multiple ApplicationsMultiple Applications

Domestic – water and space heatingDomestic – water and space heating

Commercial & Industrial – Commercial & Industrial – production of steam and electricityproduction of steam and electricity

Domestic Domestic

Active SolarActive Solar

• Water is Water is heated by heated by sunlight in sunlight in

roof top solar roof top solar collectorscollectors

Domestic Domestic


• Solar heated Solar heated water is water is used used in home water in home water heater and can heater and can

be used for be used for space heatingspace heating

Can also be used for Can also be used for production ofproduction of


• Commercial & Industrial – Commercial & Industrial – production of steam and production of steam and

electricityelectricity






Solar EnergySolar Energy PhotovoltaicsPhotovoltaics• aka – solar cellsaka – solar cells

• originally developed as exotic power originally developed as exotic power source for satellitessource for satellites

Sunlight energy (photons) Sunlight energy (photons) causes the movement of causes the movement of

electrons (current) between electrons (current) between layers of silicon to produce layers of silicon to produce

directly produce electricity from directly produce electricity from sulightsulight

PhotovoltaicsPhotovoltaics

• now routine in calculators, outdoor now routine in calculators, outdoor lighting, and other applicationslighting, and other applications

• tremendous increase in efficiencytremendous increase in efficiency

• tremendous decrease in costtremendous decrease in cost

PhotovoltaicsPhotovoltaics

• exciting developments in design exciting developments in design and applicationand application





Solar EnergySolar Energy Artificial PhotosynthesisArtificial Photosynthesis

• An early reaction in natural An early reaction in natural photosynthesis uses sunlight photosynthesis uses sunlight

energy to split water into oxygen energy to split water into oxygen and hydrogenand hydrogen


2H2H22O + sunlight O + sunlight 2H 2H22 + O + O22

• research is in progress to develop an research is in progress to develop an economical way to do this economical way to do this in vitroin vitro


2H2H22O + sunlight O + sunlight 2H 2H22 + O + O22

• this process would produce this process would produce hydrogen gashydrogen gas

Often called “the fuel of Often called “the fuel of the future”the future”

HydrogenHydrogen

Nearly an ideal fuelNearly an ideal fuel

Could be a replacement for Could be a replacement for current transportation fuelscurrent transportation fuels

The primary problem is that there is The primary problem is that there is almost no free hydrogen (Halmost no free hydrogen (H22) on earth) on earth

HydrogenHydrogen

The hydrogen is bound in The hydrogen is bound in molecules, such as water (Hmolecules, such as water (H22O)O)

Free hydrogen (HFree hydrogen (H22) must be ) must be

produced by splitting moleculesproduced by splitting molecules

HydrogenHydrogen Production of free hydrogen (HProduction of free hydrogen (H22) by ) by

splitting molecules requires a primary splitting molecules requires a primary energy sourceenergy source

Currently HCurrently H22 is produced by is produced by

electrolysis of waterelectrolysis of water

Electrolysis of water to produce HElectrolysis of water to produce H22

requires substantial electricityrequires substantial electricity

HydrogenHydrogen Hydrogen energy would be Hydrogen energy would be

more practical withmore practical with

• direct solar production of Hdirect solar production of H22

• fusion production of electricityfusion production of electricity

• solar production of electricitysolar production of electricity

Hydrogen can be used in Hydrogen can be used in combustion engines or in fuel cellscombustion engines or in fuel cells

HydrogenHydrogen

In either application, hydrogen In either application, hydrogen fuel produces little-to-no pollutionfuel produces little-to-no pollution

HydrogenHydrogen

2 H2 H22 + O + O22 2 H 2 H22O + heat energyO + heat energy

Burning hydrogen fuel in a Burning hydrogen fuel in a combustion engine produces combustion engine produces

water as the end productwater as the end product

Hydrogen Hydrogen can also be can also be used in fuel used in fuel

cells for cells for production of production of

electricityelectricity

Water is Water is again the again the byproductbyproduct

Hydrogen Hydrogen fuel cells fuel cells can also can also

run run electric electric motorsmotors



HydrogenHydrogen




• WindWind• HydropowerHydropower

• BiomassBiomass• OTECOTEC

Indirect SolarIndirect Solar

• Atmospheric movement, wind, is Atmospheric movement, wind, is due to differential heating of the due to differential heating of the

atmosphere by the sunatmosphere by the sun

Wind EnergyWind Energy How indirect solar ?How indirect solar ?

Has been used for centuriesHas been used for centuries

Wind EnergyWind Energy

Currently a well Currently a well developed technology for developed technology for production of electricityproduction of electricity

Most of current U.S. production Most of current U.S. production capacity located in Californiacapacity located in California


Large new facilities under Large new facilities under construction in Texasconstruction in Texas

Wind turbines are increasing Wind turbines are increasing in size and efficiencyin size and efficiency


Potential for substantial Potential for substantial contribution to U.S. energy needscontribution to U.S. energy needs

Wind EnergyWind Energy Many good wind energy Many good wind energy

sites located across the countrysites located across the country

The biggest problem is the The biggest problem is the variable nature of windsvariable nature of winds


• no wind -- no electricityno wind -- no electricity

There are some negatives or There are some negatives or cons with wind energycons with wind energy

Wind EnergyWind Energy Problem eased by widely Problem eased by widely

geographically located geographically located facilities connected to the facilities connected to the

national power gridnational power grid

• the wind is always blowing the wind is always blowing somewheresomewhere

Unfortunately, the rotors of Unfortunately, the rotors of wind turbines can also kill and wind turbines can also kill and

injure birdsinjure birds


• ways to minimize impacts on birds ways to minimize impacts on birds are under studyare under study





How indirect solar ?How indirect solar ?

HydropowerHydropower

• sunlight energy evaporates sunlight energy evaporates water, lifting it into the water, lifting it into the

atmosphereatmosphere

HydropowerHydropower• precipitation precipitation

from the from the atmosphere atmosphere

runs downhill runs downhill by gravityby gravity

• Energy is Energy is extracted extracted from the from the

water as it water as it runs runs

downhilldownhill


HydropowerHydropower Has been used for centuriesHas been used for centuries

Currently a well Currently a well developed technology for developed technology for production of electricityproduction of electricity

In the U.S., most of the good In the U.S., most of the good locations for big hydropower dams locations for big hydropower dams

have been exploitedhave been exploited


Around the world, many good Around the world, many good locations for big hydropower dams locations for big hydropower dams

have not been exploitedhave not been exploited

Small scale hydropower Small scale hydropower could further contribute to could further contribute to

energy needs in rural areas of energy needs in rural areas of less developed countriesless developed countries


Big hydropower dams Big hydropower dams have multiple pros and conshave multiple pros and cons


Dam opponents are calling for Dam opponents are calling for removal of some damsremoval of some dams

HydropowerHydropower Big hydropower dams -- prosBig hydropower dams -- pros

• electricity generationelectricity generation

• water reservoirwater reservoir

• flood controlflood control

• creates recreational areacreates recreational area

HydropowerHydropower Big hydropower dams -- consBig hydropower dams -- cons

• obstacle to fish migrationobstacle to fish migration

• floods landfloods land

• disrupts natural water cycledisrupts natural water cycle

• destroys recreational areadestroys recreational area





Biomass EnergyBiomass Energy How indirect solar ?How indirect solar ?

• Energy of sunlight used in Energy of sunlight used in photosynthesis to form photosynthesis to form

complex organic compoundscomplex organic compounds

Multiple formsMultiple forms

Biomass EnergyBiomass Energy

• direct combustiondirect combustion• waste to energywaste to energy

• conversion to methaneconversion to methane

• conversion to alcoholconversion to alcohol


A concern common to all A concern common to all forms of biomass energy is the forms of biomass energy is the

potential for land degradation and potential for land degradation and soil depletionsoil depletion




• BiomassBiomass

• OTECOTEC


OOcean cean TThermal hermal EEnergy nergy

CConversiononversion

OTECOTECWhat is it ?What is it ?

An acronym forAn acronym for

OTECOTEC How indirect solar ?How indirect solar ?

• Utilizes the thermal gradient Utilizes the thermal gradient formed in bodies of water due to formed in bodies of water due to

warming of surface water by warming of surface water by sunlight energysunlight energy

First proposed more First proposed more than a century agothan a century ago

OTECOTEC

Currently an Currently an experimental technologyexperimental technology

A fluid with a low boiling A fluid with a low boiling point is circulated in pipes point is circulated in pipes

between warm surface water between warm surface water and cold deep waterand cold deep water

OTECOTEC

The fluid turns to steam at the temperature of surface

water and the steam spins a turbo generator to produce

electricity

OTECOTEC

The steam recondenses to The steam recondenses to fluid as it passes into the cold fluid as it passes into the cold

temperature of deep watertemperature of deep water

OTECOTEC

The fluid is then pumped The fluid is then pumped back to the surface to repeat back to the surface to repeat

the cyclethe cycle

Has potential to benefit Has potential to benefit coastal and island areascoastal and island areas

OTECOTEC

However, OTEC technology However, OTEC technology does not seem to be progressing does not seem to be progressing

and there is no clear timetable for and there is no clear timetable for commercial applicationcommercial application



HydrogenHydrogen



Ocean tides are due to Ocean tides are due to gravitational attraction of the gravitational attraction of the

moon – lunar energymoon – lunar energy

Tidal PowerTidal Power

Water Water flowing in flowing in or out with or out with

the tide the tide spins turbo spins turbo generators generators to produce to produce electricityelectricity


Extremely high tides Extremely high tides requiredrequired


Relatively few good sites Relatively few good sites in the worldin the world

Required tidal dams disrupt Required tidal dams disrupt intertidal biological communitiesintertidal biological communities


Seems destined for failureSeems destined for failure



HydrogenHydrogen



Not a truly renewable Not a truly renewable energy sourceenergy source

Geothermal EnergyGeothermal Energy

Thought to have a long period Thought to have a long period of use and often classified with of use and often classified with

renewable energiesrenewable energies

Heat from the Earth’s Heat from the Earth’s interior provides the energyinterior provides the energy


Theoretically available Theoretically available anywhere on Earthanywhere on Earth – if go – if go

deep enoughdeep enough


Good geothermal sites are Good geothermal sites are where “hot rock” is located close where “hot rock” is located close

to the surfaceto the surface


Hot rock heats water to Hot rock heats water to steam to spin a turbo generator steam to spin a turbo generator

to produce electricityto produce electricity


Geothermal EnergyGeothermal Energy Currently a well Currently a well

developed technology for developed technology for production of electricityproduction of electricity

Many good geothermal sites Many good geothermal sites located across the countrylocated across the country




HydrogenHydrogen



Renewable energies Renewable energies are available today !are available today !

There are enormous human There are enormous human and environmental “costs” and environmental “costs”

associated with continued use of associated with continued use of fossil fuelsfossil fuels

Documents

Energy Resources. Energy What is Energy ? Many of us would answer…. electricity orgasoline or maybe nuclear power