11

Solar EnergySolar Energy

Raymond F CarlRaymond F Carl

22

History of Solar EnergyHistory of Solar EnergyTypes of Solar Energy TechnologiesTypes of Solar Energy Technologies

PassivePassiveConcentration Concentration PhotovoltaicPhotovoltaic

Photovoltaic Cell (Solar Cells)Photovoltaic Cell (Solar Cells)Materials and Efficiency Materials and Efficiency

Inorganic Inorganic OrganicOrganic

Concerns about risks of toxic materials in PV CellsConcerns about risks of toxic materials in PV Cells

33

The History of Solar EnergyThe History of Solar Energy Greeks used passive solar to heat Buildings (400 BC)Greeks used passive solar to heat Buildings (400 BC) Romans improved by using glass to trap heat in the Romans improved by using glass to trap heat in the

buildings and green houses (100 AD)buildings and green houses (100 AD) 17001700 Antoine LaVoisier built a solar heater Antoine LaVoisier built a solar heater 1839 1839 French physicist Antoine-Cesar Becquerel French physicist Antoine-Cesar Becquerel

observed that shining light on an electrode submerged observed that shining light on an electrode submerged in a conductive solution would create an electric in a conductive solution would create an electric currentcurrent

18601860 The First Solar Motor heated water used to The First Solar Motor heated water used to drive a steam motor Auguste Mouchoutdrive a steam motor Auguste Mouchout

18831883 American Charles Fritts described the first solar American Charles Fritts described the first solar cells which was made from selenium waferscells which was made from selenium wafers

44

The History of Solar EnergyThe History of Solar Energy 1900 1900 The photoelectric effect was discovered The photoelectric effect was discovered 1904 1904 Henry E Willsie first use of solar energy at night Henry E Willsie first use of solar energy at night 19161916 Millikan provided experimental proof of the Millikan provided experimental proof of the

photoelectric effect photoelectric effect 19181918 Polish scientist Czochralski developed a way to grow Polish scientist Czochralski developed a way to grow

single-crystal silicon single-crystal silicon 19411941 American Russell Ohl invented a silicon solar cell American Russell Ohl invented a silicon solar cell 1954 1954 Bell Labs researchers Pearson Chapin and Fuller Bell Labs researchers Pearson Chapin and Fuller

reported their discovery of 45 efficient silicon solar cells reported their discovery of 45 efficient silicon solar cells 1950rsquos 1950rsquos Solar cells developed for satellites Solar cells developed for satellites 19601960 Hoffman Electronics achieved 14 efficient PV cells Hoffman Electronics achieved 14 efficient PV cells 19731973 OPEC Energy Crisis causes US to re-examine use of OPEC Energy Crisis causes US to re-examine use of

renewable energy sources federal and state tax credits result renewable energy sources federal and state tax credits result in rapid growth for a new solar industry in rapid growth for a new solar industry

55

PassivePassive

Direct Solar GainDirect Solar Gain South facing large South facing large

windowswindows Floors walls ceiling Floors walls ceiling

used to trap heat The used to trap heat The heat is released at heat is released at night night

66

PassivePassive

Indirect Solar GainIndirect Solar Gain Thermal storage

materials are placed between the interior habitable space and the sun

Can use vents in wall to help circulate hot air through room

77

PassivePassive

Isolated Solar GainIsolated Solar Gain Uses a fluid (liquid or air) Uses a fluid (liquid or air)

to collect heat in a to collect heat in a flat flat plate solar collectorplate solar collector attached to the structure attached to the structure

88

ConcentrationConcentration

Power towersPower towers Large field of mirriors Large field of mirriors

is used to concentrate is used to concentrate the sunlightthe sunlight

Concentrated Sunlight Concentrated Sunlight is used to heat molten is used to heat molten salt salt

99

ConcentrationConcentration

Trough CollectorsTrough Collectors Uses parabolic mirrors Uses parabolic mirrors

to heat a fluid in an to heat a fluid in an absorbing tubeabsorbing tube

Hot fluid is used to boil Hot fluid is used to boil water to run a steam water to run a steam generator generator

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

22

History of Solar EnergyHistory of Solar EnergyTypes of Solar Energy TechnologiesTypes of Solar Energy Technologies

PassivePassiveConcentration Concentration PhotovoltaicPhotovoltaic

Photovoltaic Cell (Solar Cells)Photovoltaic Cell (Solar Cells)Materials and Efficiency Materials and Efficiency

Inorganic Inorganic OrganicOrganic

Concerns about risks of toxic materials in PV CellsConcerns about risks of toxic materials in PV Cells

33

The History of Solar EnergyThe History of Solar Energy Greeks used passive solar to heat Buildings (400 BC)Greeks used passive solar to heat Buildings (400 BC) Romans improved by using glass to trap heat in the Romans improved by using glass to trap heat in the

buildings and green houses (100 AD)buildings and green houses (100 AD) 17001700 Antoine LaVoisier built a solar heater Antoine LaVoisier built a solar heater 1839 1839 French physicist Antoine-Cesar Becquerel French physicist Antoine-Cesar Becquerel

observed that shining light on an electrode submerged observed that shining light on an electrode submerged in a conductive solution would create an electric in a conductive solution would create an electric currentcurrent

18601860 The First Solar Motor heated water used to The First Solar Motor heated water used to drive a steam motor Auguste Mouchoutdrive a steam motor Auguste Mouchout

18831883 American Charles Fritts described the first solar American Charles Fritts described the first solar cells which was made from selenium waferscells which was made from selenium wafers

44

The History of Solar EnergyThe History of Solar Energy 1900 1900 The photoelectric effect was discovered The photoelectric effect was discovered 1904 1904 Henry E Willsie first use of solar energy at night Henry E Willsie first use of solar energy at night 19161916 Millikan provided experimental proof of the Millikan provided experimental proof of the

photoelectric effect photoelectric effect 19181918 Polish scientist Czochralski developed a way to grow Polish scientist Czochralski developed a way to grow

single-crystal silicon single-crystal silicon 19411941 American Russell Ohl invented a silicon solar cell American Russell Ohl invented a silicon solar cell 1954 1954 Bell Labs researchers Pearson Chapin and Fuller Bell Labs researchers Pearson Chapin and Fuller

reported their discovery of 45 efficient silicon solar cells reported their discovery of 45 efficient silicon solar cells 1950rsquos 1950rsquos Solar cells developed for satellites Solar cells developed for satellites 19601960 Hoffman Electronics achieved 14 efficient PV cells Hoffman Electronics achieved 14 efficient PV cells 19731973 OPEC Energy Crisis causes US to re-examine use of OPEC Energy Crisis causes US to re-examine use of

renewable energy sources federal and state tax credits result renewable energy sources federal and state tax credits result in rapid growth for a new solar industry in rapid growth for a new solar industry

55

PassivePassive

Direct Solar GainDirect Solar Gain South facing large South facing large

windowswindows Floors walls ceiling Floors walls ceiling

used to trap heat The used to trap heat The heat is released at heat is released at night night

66

PassivePassive

Indirect Solar GainIndirect Solar Gain Thermal storage

materials are placed between the interior habitable space and the sun

Can use vents in wall to help circulate hot air through room

77

PassivePassive

Isolated Solar GainIsolated Solar Gain Uses a fluid (liquid or air) Uses a fluid (liquid or air)

to collect heat in a to collect heat in a flat flat plate solar collectorplate solar collector attached to the structure attached to the structure

88

ConcentrationConcentration

Power towersPower towers Large field of mirriors Large field of mirriors

is used to concentrate is used to concentrate the sunlightthe sunlight

Concentrated Sunlight Concentrated Sunlight is used to heat molten is used to heat molten salt salt

99

ConcentrationConcentration

Trough CollectorsTrough Collectors Uses parabolic mirrors Uses parabolic mirrors

to heat a fluid in an to heat a fluid in an absorbing tubeabsorbing tube

Hot fluid is used to boil Hot fluid is used to boil water to run a steam water to run a steam generator generator

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

33

The History of Solar EnergyThe History of Solar Energy Greeks used passive solar to heat Buildings (400 BC)Greeks used passive solar to heat Buildings (400 BC) Romans improved by using glass to trap heat in the Romans improved by using glass to trap heat in the

buildings and green houses (100 AD)buildings and green houses (100 AD) 17001700 Antoine LaVoisier built a solar heater Antoine LaVoisier built a solar heater 1839 1839 French physicist Antoine-Cesar Becquerel French physicist Antoine-Cesar Becquerel

observed that shining light on an electrode submerged observed that shining light on an electrode submerged in a conductive solution would create an electric in a conductive solution would create an electric currentcurrent

18601860 The First Solar Motor heated water used to The First Solar Motor heated water used to drive a steam motor Auguste Mouchoutdrive a steam motor Auguste Mouchout

18831883 American Charles Fritts described the first solar American Charles Fritts described the first solar cells which was made from selenium waferscells which was made from selenium wafers

44

The History of Solar EnergyThe History of Solar Energy 1900 1900 The photoelectric effect was discovered The photoelectric effect was discovered 1904 1904 Henry E Willsie first use of solar energy at night Henry E Willsie first use of solar energy at night 19161916 Millikan provided experimental proof of the Millikan provided experimental proof of the

photoelectric effect photoelectric effect 19181918 Polish scientist Czochralski developed a way to grow Polish scientist Czochralski developed a way to grow

single-crystal silicon single-crystal silicon 19411941 American Russell Ohl invented a silicon solar cell American Russell Ohl invented a silicon solar cell 1954 1954 Bell Labs researchers Pearson Chapin and Fuller Bell Labs researchers Pearson Chapin and Fuller

reported their discovery of 45 efficient silicon solar cells reported their discovery of 45 efficient silicon solar cells 1950rsquos 1950rsquos Solar cells developed for satellites Solar cells developed for satellites 19601960 Hoffman Electronics achieved 14 efficient PV cells Hoffman Electronics achieved 14 efficient PV cells 19731973 OPEC Energy Crisis causes US to re-examine use of OPEC Energy Crisis causes US to re-examine use of

renewable energy sources federal and state tax credits result renewable energy sources federal and state tax credits result in rapid growth for a new solar industry in rapid growth for a new solar industry

55

PassivePassive

Direct Solar GainDirect Solar Gain South facing large South facing large

windowswindows Floors walls ceiling Floors walls ceiling

used to trap heat The used to trap heat The heat is released at heat is released at night night

66

PassivePassive

Indirect Solar GainIndirect Solar Gain Thermal storage

materials are placed between the interior habitable space and the sun

Can use vents in wall to help circulate hot air through room

77

PassivePassive

Isolated Solar GainIsolated Solar Gain Uses a fluid (liquid or air) Uses a fluid (liquid or air)

to collect heat in a to collect heat in a flat flat plate solar collectorplate solar collector attached to the structure attached to the structure

88

ConcentrationConcentration

Power towersPower towers Large field of mirriors Large field of mirriors

is used to concentrate is used to concentrate the sunlightthe sunlight

Concentrated Sunlight Concentrated Sunlight is used to heat molten is used to heat molten salt salt

99

ConcentrationConcentration

Trough CollectorsTrough Collectors Uses parabolic mirrors Uses parabolic mirrors

to heat a fluid in an to heat a fluid in an absorbing tubeabsorbing tube

Hot fluid is used to boil Hot fluid is used to boil water to run a steam water to run a steam generator generator

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

44

The History of Solar EnergyThe History of Solar Energy 1900 1900 The photoelectric effect was discovered The photoelectric effect was discovered 1904 1904 Henry E Willsie first use of solar energy at night Henry E Willsie first use of solar energy at night 19161916 Millikan provided experimental proof of the Millikan provided experimental proof of the

photoelectric effect photoelectric effect 19181918 Polish scientist Czochralski developed a way to grow Polish scientist Czochralski developed a way to grow

single-crystal silicon single-crystal silicon 19411941 American Russell Ohl invented a silicon solar cell American Russell Ohl invented a silicon solar cell 1954 1954 Bell Labs researchers Pearson Chapin and Fuller Bell Labs researchers Pearson Chapin and Fuller

reported their discovery of 45 efficient silicon solar cells reported their discovery of 45 efficient silicon solar cells 1950rsquos 1950rsquos Solar cells developed for satellites Solar cells developed for satellites 19601960 Hoffman Electronics achieved 14 efficient PV cells Hoffman Electronics achieved 14 efficient PV cells 19731973 OPEC Energy Crisis causes US to re-examine use of OPEC Energy Crisis causes US to re-examine use of

renewable energy sources federal and state tax credits result renewable energy sources federal and state tax credits result in rapid growth for a new solar industry in rapid growth for a new solar industry

55

PassivePassive

Direct Solar GainDirect Solar Gain South facing large South facing large

windowswindows Floors walls ceiling Floors walls ceiling

used to trap heat The used to trap heat The heat is released at heat is released at night night

66

PassivePassive

Indirect Solar GainIndirect Solar Gain Thermal storage

materials are placed between the interior habitable space and the sun

Can use vents in wall to help circulate hot air through room

77

PassivePassive

Isolated Solar GainIsolated Solar Gain Uses a fluid (liquid or air) Uses a fluid (liquid or air)

to collect heat in a to collect heat in a flat flat plate solar collectorplate solar collector attached to the structure attached to the structure

88

ConcentrationConcentration

Power towersPower towers Large field of mirriors Large field of mirriors

is used to concentrate is used to concentrate the sunlightthe sunlight

Concentrated Sunlight Concentrated Sunlight is used to heat molten is used to heat molten salt salt

99

ConcentrationConcentration

Trough CollectorsTrough Collectors Uses parabolic mirrors Uses parabolic mirrors

to heat a fluid in an to heat a fluid in an absorbing tubeabsorbing tube

Hot fluid is used to boil Hot fluid is used to boil water to run a steam water to run a steam generator generator

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

55

PassivePassive

Direct Solar GainDirect Solar Gain South facing large South facing large

windowswindows Floors walls ceiling Floors walls ceiling

used to trap heat The used to trap heat The heat is released at heat is released at night night

66

PassivePassive

Indirect Solar GainIndirect Solar Gain Thermal storage

materials are placed between the interior habitable space and the sun

Can use vents in wall to help circulate hot air through room

77

PassivePassive

Isolated Solar GainIsolated Solar Gain Uses a fluid (liquid or air) Uses a fluid (liquid or air)

to collect heat in a to collect heat in a flat flat plate solar collectorplate solar collector attached to the structure attached to the structure

88

ConcentrationConcentration

Power towersPower towers Large field of mirriors Large field of mirriors

is used to concentrate is used to concentrate the sunlightthe sunlight

Concentrated Sunlight Concentrated Sunlight is used to heat molten is used to heat molten salt salt

99

ConcentrationConcentration

Trough CollectorsTrough Collectors Uses parabolic mirrors Uses parabolic mirrors

to heat a fluid in an to heat a fluid in an absorbing tubeabsorbing tube

Hot fluid is used to boil Hot fluid is used to boil water to run a steam water to run a steam generator generator

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

66

PassivePassive

Indirect Solar GainIndirect Solar Gain Thermal storage

materials are placed between the interior habitable space and the sun

Can use vents in wall to help circulate hot air through room

77

PassivePassive

Isolated Solar GainIsolated Solar Gain Uses a fluid (liquid or air) Uses a fluid (liquid or air)

to collect heat in a to collect heat in a flat flat plate solar collectorplate solar collector attached to the structure attached to the structure

88

ConcentrationConcentration

Power towersPower towers Large field of mirriors Large field of mirriors

is used to concentrate is used to concentrate the sunlightthe sunlight

Concentrated Sunlight Concentrated Sunlight is used to heat molten is used to heat molten salt salt

99

ConcentrationConcentration

Trough CollectorsTrough Collectors Uses parabolic mirrors Uses parabolic mirrors

to heat a fluid in an to heat a fluid in an absorbing tubeabsorbing tube

Hot fluid is used to boil Hot fluid is used to boil water to run a steam water to run a steam generator generator

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

77

PassivePassive

Isolated Solar GainIsolated Solar Gain Uses a fluid (liquid or air) Uses a fluid (liquid or air)

to collect heat in a to collect heat in a flat flat plate solar collectorplate solar collector attached to the structure attached to the structure

88

ConcentrationConcentration

Power towersPower towers Large field of mirriors Large field of mirriors

is used to concentrate is used to concentrate the sunlightthe sunlight

Concentrated Sunlight Concentrated Sunlight is used to heat molten is used to heat molten salt salt

99

ConcentrationConcentration

Trough CollectorsTrough Collectors Uses parabolic mirrors Uses parabolic mirrors

to heat a fluid in an to heat a fluid in an absorbing tubeabsorbing tube

Hot fluid is used to boil Hot fluid is used to boil water to run a steam water to run a steam generator generator

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

88

ConcentrationConcentration

Power towersPower towers Large field of mirriors Large field of mirriors

is used to concentrate is used to concentrate the sunlightthe sunlight

Concentrated Sunlight Concentrated Sunlight is used to heat molten is used to heat molten salt salt

99

ConcentrationConcentration

Trough CollectorsTrough Collectors Uses parabolic mirrors Uses parabolic mirrors

to heat a fluid in an to heat a fluid in an absorbing tubeabsorbing tube

Hot fluid is used to boil Hot fluid is used to boil water to run a steam water to run a steam generator generator

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

99

ConcentrationConcentration

Trough CollectorsTrough Collectors Uses parabolic mirrors Uses parabolic mirrors

to heat a fluid in an to heat a fluid in an absorbing tubeabsorbing tube

Hot fluid is used to boil Hot fluid is used to boil water to run a steam water to run a steam generator generator

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1010

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Photoelectric effectPhotoelectric effect PN junction directly PN junction directly

converts sunlight into converts sunlight into electricityelectricity

Electricity can be stored Electricity can be stored for later useage or used for later useage or used on demandon demand

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1111

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Multiple PN junction Cell Multiple PN junction Cell has multiple transparent has multiple transparent layerslayers

Top layer absorbs the Top layer absorbs the high energy light and high energy light and

passes rest throughpasses rest through

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1212

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Solar Cells transform light Solar Cells transform light to electricityto electricity

Controller regulates were Controller regulates were the charge is directedthe charge is directed

Batteries store the energyBatteries store the energy Inverter converts from DC Inverter converts from DC

to ACto AC

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1313

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thick Crystalline MaterialsThick Crystalline Materials

Crystalline SiliconCrystalline SiliconSingle-crystal Single-crystal MulticrystallineMulticrystallineEdge-defined film-fed growth Edge-defined film-fed growth DendriticDendritic

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1414

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Inorganic MaterialsInorganic Materials Thin Film MaterialsThin Film Materials

Amorphous Silicon (a-Si) Amorphous Silicon (a-Si) Cadmium Telluride (CdTe) Cadmium Telluride (CdTe) Copper Indium Diselenide (CuInSe2 or CIS) Copper Indium Diselenide (CuInSe2 or CIS)

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1515

Inorganic MaterialsInorganic Materials ConcernsConcerns

Use of toxic metals like CadmiumUse of toxic metals like Cadmium Use of toxic gasses in the manufacturing of Use of toxic gasses in the manufacturing of

PV silane PV silane hydrogen selenide Can the materials be recycled or are they

destined for landfills

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1616

Inorganic MaterialsInorganic Materials Concerns Answered Concerns Answered

Cd is produced as a byproduct of Zn production and can either be put to beneficial uses or discharged into the environment

CdTe in PV is much safer than other current Cd uses CdTe PV uses Cd 2500 times more efficiently than NiCd

batteries 1048708Occupational health risks are well managed -

Continuous vigilance is required 1048708Absolutely no emissions during PV operation 1048708Risk from fire emissions is minimal 1048708Disposal of spent modules is an environmental issue ndash

Reducing the amount of CdTe will alleviate the problem Recycling will resolve most environmental concerns

Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 140 g CdGWh in fine dust Burning of Coal produces 2 g CdGWh be emitted from the stack Burning of Coal produces 2 g CdGWh be emitted from the stack

(for plants with perfectly maintained electrostatic precipitators or (for plants with perfectly maintained electrostatic precipitators or baghouses operating at 986 efficiencybaghouses operating at 986 efficiency

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1717

Inorganic MaterialsInorganic MaterialsConcerns AnsweredConcerns Answered

Manufacturers use gas handling systems to reduce risk and use careful engineering and administrative controls to prevent exposure of workers or the public

Landfill leaching is a modest concern only because PV materials are largely encased in glass or plastic and many are insoluble

Because of dispersed use and small amounts of semiconductor material per cell PV recycling will be challenging Machinery for dismantling modules for recycling has been developed and recycling systems for batteries and electronics provide useful models

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1818

Photovoltaic Cells (Solar Cells)Photovoltaic Cells (Solar Cells)

Organic MaterialsOrganic Materials Pure and chemically Pure and chemically

modified fullerenesmodified fullerenes polythiophene derivatives polythiophene derivatives

polyphenylene vinylene polyphenylene vinylene

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

1919

Organic MaterialsOrganic MaterialsCurrent obstaclesCurrent obstacles

All of the PV cells made from Organic molecules All of the PV cells made from Organic molecules decompose rapidlydecompose rapidly

Only 3-6 conversion of solar energy to electricityOnly 3-6 conversion of solar energy to electricity

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

2020

ConclusionConclusion

Using a combination of Passive solar Using a combination of Passive solar energy and photovoltaic cells can lessen energy and photovoltaic cells can lessen pollutionpollution

Concerns with use of Cadmium in PV cells Concerns with use of Cadmium in PV cells is exaggerated when compared to is exaggerated when compared to electricity produced from coalelectricity produced from coal

More research is needed and being done More research is needed and being done Cost of Solar system will come down in Cost of Solar system will come down in

price when production increasesprice when production increases

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml

2121

SourcesSources

httpwwwabcnetaurnscienceearthstoriess225110htm

httpwwwsolarenergycominfo_historyhtml httppvpowercompvtechshtml httpwwwadsdyescomfullereneshtml httpwwwazsolarcentercomdesignpas-2htm httpwwweereenergygovRE

solar_concentratinghtml