1

Sustainability of Large Deployment of Photovoltaics: Environmental & Grid Integration Research

Sustainability of Large Deployment of Photovoltaics: Environmental & Grid Integration Research

www.clca.columbia.eduwww.pv.bnl.gov

Vasilis FthenakisCenter for Life Cycle Analysis

Columbia Universityand

National Photovoltaics Environmental Research CenterBrookhaven National Laboratory

2Source: PV Market Outlook European Photovoltaic Industry Association 2009

Photovoltaic Global Sales and Projections

Doubling of added capacity every 2 years.

MW/yr

3

A Solar Grand PlanA Solar Grand Plan

Energy Policy 37 (2009)

By 2050 renewable energy to supply 69% of electricity, 35% of total energy needs of the U.S.Zweibel, Mason, Fthenakis

.

4

DOE-EERE Solar Vision Study Report is in review, not to be citedDOE-EERE Solar Vision Study Report is in review, not to be cited

PV Capacity Projections: United States 2030PV Capacity Projections: United States 2030

5

PV –Sustainability Criteria PV –Sustainability Criteria

Low Cost

ResourceAvailability

Lowest Environmental Impact

Affordability in a competitive world

Te in CdTe In in CIGS Ge in a-SiGe & III/VAg in c-Si

Lower than alternatives Life Cycle Impacts & Risks

Affordability - Cost ReductionsAffordability - Cost Reductions

Prices and Production Costs of PV Modules

$1

$10

$100

1 10 100 1,000 10,000 100,000 1,000,000

Cumulative Production (MWp)

Mod

ule

Pric

e (2

006$

/Wp)

Historical Prices

1980

2006

2004

a-Si (Unisolar)Thin Films

CdTe (First Solar)

2006

Courtesy R. Margolis, NRELUpdate V. Fthenakis

avg 2010 costs $0.7/W

Crystalline Si

avg 2010 costs $1.5-2 /W2010

7

Affordability: Projected PV Growth and Electricity Price TargetsAffordability: Projected PV Growth and Electricity Price Targets

Source: J. Lushetsky, Solar Technologies Program, US-DOE, 25th EUPV, Valencia, Spain, Sept. 2010

Geographic LocationsPhoenix, AZKansas City, MONew York, NY

Financing ConditionsLow: 8.2% High: 9.9%

8

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

2010 2020 2030 2040 2050 2060 2070 2080 2090 2100

Te (M

T/yr

)

Tellurium for PV* from Copper SmeltersTellurium for PV* from Copper SmeltersTellurium Availability for PV* (MT/yr)

•Global Efficiency of Extracting Te from anode slimes increases to 80% by 2030 (low scenario);90% by 2040 (high scenario)

* 322 MT/yr Te demand for other uses has been subtractedAll the growth in Te production is allocated to PV

Low

High

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

2010 2020 2030 2040 2050 2060 2070 2080 2090 2100

Te (M

T/yr

)

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

2010

Te (M

T/yr

)

2010 2020 2030 2040 2050 2060 2070 2080 2090 2100

Te Availability for PV: Primary + RecycledTe Availability for PV: Primary + Recycled

Tellurium Availability for PV (MT/yr)

Low

High

Recycling every 30-yrs 10% loss in collection10% loss in recycling

Fthenakis V., Renewable & Sustainable Energy Reviews 13, 2746, 2009

CdTe PV Production Constraints CdTe PV Production Constraints Annual (GW/yr)

Most likely

Optimistic

Conservative

Most likely

Optimistic

Fthenakis V., Renewable & Sustainable Energy Reviews 13, 2746, 2009

Cumulative (TW)

Optimistic

Most likely

Conservative

Production can increase with direct mining starting at ~2015

11

Life Cycle Environmental ImpactsLife Cycle Environmental Impacts

Raw Material

Acquisition

Material Processing

Manufacture Decommiss-ioning

Treatment Disposal

Installation/Operation

Recycling

M, Q

E

M, Q M, Q M, Q M, Q M, Q

E E E E E

M, Q: material and energy inputs

E: effluents (air, water, solid)

M, Q

E

12

Life Cycle Environmental ImpactsLife Cycle Environmental Impacts

Raw Material

Acquisition

Material Processing

Manufacture Decommiss-ioning

Treatment Disposal

Operation

Recycling

M, Q

E

M, Q M, Q M, Q M, Q M, Q

E E E E E

M, Q: material and energy inputs

E: effluents (air, water, solid)

M, Q

E

Accidental emissions

Separations,Recovery

Experimental Research at BNL

13

Comparative Life-Cycle AnalysisComparative Life-Cycle Analysis

Energy Payback Times (EPBT) Greenhouse Gas EmissionsResource Use (materials, water, land)EH&S Risks

Zero impact technology does not exist èCompare with other energy producing technologies as benchmarks

14

Energy Payback Times (EPBT)Energy Payback Times (EPBT)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

Ribbon-Si13.2%

Multi-Si13.2%

Mono-Si14.0%

CdTe 10.9%

EPB

T (Y

ears

)

BOSFrameFramelessModule

1.8 1.9

0.8

1.3

Insolation: 1700 kWh/m2-yr

- Fthenakis et al., EUPV, 2009- deWild 2009, EUPV, 2009- Alsema & de Wild, Material Research Society, Symposium, 895, 73, 2006- deWild & Alsema, Material Research Society, Symposium, 895, 59, 2006- Fthenakis & Kim, Material Research Society, Symposium, 895, 83, 2006- Fthenakis & Alsema, Progress in Photovoltaics, 14, 275, 2006

Based on data from 13 US and European PV manufacturers

15

Greenhouse Gas (GHG) EmissionsGreenhouse Gas (GHG) EmissionsInsolation: 1700 kWh/m2-yr

0

10

20

30

40

50

Ribbon13.2%

Multi-Si13.2%

Mono-Si14%

CdTe 10.9%

CO

2-eq

(g/k

Wh)

BOSFrameFramelessModule

- Fthenakis & Kim, Encyclopedia of Energy, in press- deWild 2009, EUPV, 2009- Fthenakis et al., EUPV, 2009- Fthenakis & Kim, ES&T, 42, 2168, 2008- Alsema & de Wild, Material Research Society, Symposium, 895, 73, 2006- deWild & Alsema, Material Research Society, Symposium, 895, 59, 2006- Fthenakis & Kim, Material Research Society, Symposium, 895, 83, 2006- Fthenakis & Alsema, Progress in Photovoltaics, 14, 275, 2006

16

0

200

400

600

800

1000

1200

1400

Coal (Kim andDale 2005)

Natural Gas(Kim and Dale

2005)

Petroleum(Kim and Dale

2005)

Nuclear(Baseline -

Fthenakis andKim, 2007

PV, CdTe(Fthenakiset al, 2008)

PV, mc-Si,(Fthenakis et al, 2008)

GH

G (g

CO

2-eq

./kW

h)

MaterialsOperationTransportationFuel Production

GHG Emissions from Life Cycle of Electricity Production: ComparisonsGHG Emissions from Life Cycle of Electricity Production: Comparisons

24 18 30

California Energy Commission, Nuclear Issues Workshop, June 2007 Fthenakis & Kim, Life Cycle Emissions…, Energy Policy, 35, 2549, 2007Fthenakis & Kim, ES&T, 42, 2168, 2008

10.9% 13.2%

17

Sinzheim, Germany, with permission from Juwi, 2006

1.4MW

Dual and Ecological-friendly Use of LandDual and Ecological-friendly Use of Land

Does PV use a lot of land ?

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Land requirement for US surface coal mining: 320 m2 /GWh

More Land is used by the Coal Life Cycle than PVMountain Top Coal MiningRawl, West Virginia

Fthenakis V. and Kim H.C., Sustainable and Renewable Energy Reviews, 2009

Land requirement for PV in the SW:310 m2 /GWh

PV Plant, Tucson Electric Power, Springerville, Arizona

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CdTe PV Product Life –Accidental ReleasesCdTe PV Product Life –Accidental Releases

Leaching from shuttered modules• 10 mm fragments -Rain-worst-case scenario- “ leached Cd concentration in the

collected water is no higher than the German drinking water concentration.” (Steinberger, Frauhoffer Institute Solid State Technology, Progress in Photovoltaics, 1998)

• < 4 mm fragments “Leached Cd exceeds the limits for disposal in inert landfill but is lower than limits for ordinary landfills”(Okkenhaug, Norgegian Geotechnical Institute, Report, 2010)

• < 2 mm fragments “CdTe PV sample failed California TTLC and STLC tests”

(Sierra Analytical Labs for the “Non-Toxic Solar Alliance”, 2010)

All PV modules would fail the California tests

c-Si for Ag, Pb, and Cu (ribbon), CIGS for Se; a-Si marginally for Ag

Eberspacher & Fthenakis, 26th IEEEPVSC, 1997; Eberspacher 1998

We advocate for all PV modules to be recycled at the end of their life

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CdTe PV Product Life –Accidental ReleasesCdTe PV Product Life –Accidental Releases

PV Roof-top fires

Negligible emissions during firesFthenakis, Renewable and Sustainable Energy Reviews, 2004,

Fthenakis et al., Progress in Photovoltaics, 2005

Based on standard protocols by the ASTM and ULExpert Peer reviews by:BNL, US-DOE, 2004EC-JRC, 2004German Ministry of the Environment, (BMU), 2005French Ministry of Ecology, Energy, 2009

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CdTe PV Fire-Simulation Tests: XRF AnalysisCdTe PV Fire-Simulation Tests: XRF Analysis

Heat

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Cd (counts)

posi

tion

(mm

)

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posi

tion

(mm

)

XRF-micro-probing –Cd Distribution in PV Glass1000 °C, right end of sample

XRF-micro-spectroscopy -Cd Mapping in PV Glass1000 °C, Section taken from middle of sample

Fthenakis, Fuhrman, Heiser, Lanzirotti, Fitts and Wang, Progress in Photovoltaics, 2005

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Zr (counts)

posit

ion (m

m)

XRF-micro-probing -Cd & Zr distribution in PV sample Unheated Sample -Vertical Cross Section

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XRF-micro-probe -Cd distribution in PV sample760 °C, Section taken from middle of sampleXRF-micro-probe -Cd distribution in PV sample760 °C, Section taken from middle of sample

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XRF-micro-probe -Cd distribution in PV sample1000 °C, Section taken from middle of sampleXRF-micro-probe -Cd distribution in PV sample1000 °C, Section taken from middle of sample

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XRF-micro-probing -Cd distribution in PV sample1000 °C, Section taken from right side of sampleXRF-micro-probing -Cd distribution in PV sample1000 °C, Section taken from right side of sample

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tion

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tion

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tion

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XRF-micro-probing -Cd distribution in PV sample1100 °C, Section taken from middle of sampleXRF-micro-probing -Cd distribution in PV sample1100 °C, Section taken from middle of sample

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tion

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tion

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Atmospheric Cd Emissions from the Life-Cycle of CdTe PV Modules –Reference CaseAtmospheric Cd Emissions from the Life-

Cycle of CdTe PV Modules –Reference Case

Process (g Cd/ton Cd*) (% ) (mg Cd/GWh)1. Mining of Zn ores 2.7 0.58 0.022. Zn Smelting/Refining 40 0.58 0.303. Cd purification 6 100 7.794. CdTe Production 6 100 7.795. CdTe PV Manufacturing 0.4* 100 0.52*6. CdTe PV Operation 0.05 100 0.067. CdTe PV Recycling 0.1* 100 0.13*TOTAL EMISSIONS 16.55

Fthenakis V. Renewable and Sustainable Energy Reviews, 8, 303-334, 2004

* 2009 updates

28

Total Life-Cycle Cd Atmospheric EmissionsTotal Life-Cycle Cd Atmospheric Emissions

0.02

0.23

0

0.05

0.1

0.15

0.2

0.25

Cd direct emissions Cd indirect emissions

g Cd

/GW

h

Indirect emissions, due to fossil fuels in the electricity mix in the life-cycle of CdTe PV, are more than 10x higher than direct emissions

3.70.3

44.3

0.90

10

20

30

40

50

0.4 0.7 0.6 0.2

g C

d/G

Wh

Fthenakis and Kim, Thin-Solid Films, 515(15), 5961, 2007Fthenakis, Kim & Alsema, Environ. Sci. Technol, 42, 2168, 2008

29

End-of-life Issues of PV modulesEnd-of-life Issues of PV modules Rapid growth of PV market will result in an

eventual waste disposal issue 25+ years after module installation

Potential of environmental impacts from uncontrolled disposal of PV

30

Recycling of Spent ModulesRecycling of Spent Modules

PV recycling will resolve environmental concerns and will create secondary sources of materials that benefit the environment

CdTe PV recycling is technically and economically feasible

31

The Triangle of SuccessThe Triangle of Success

Low Cost

ResourceAvailability Lowest Environmental Impact

Recycling

§ Major PV Sustainability metrics include cost, resource availability, and environmental impacts

§ These three aspects are closely related; recycling spent modules will become increasingly important in resolving cost, resource, and environmental constraints to large scales of sustainable growth

§ Environmental sustainability should be examined in a holistic, life cycle, comparative framework

email: vmf5@columbia.eduwww.clca.columbia.eduwww.pv.bnl.gov

ConclusionConclusion