Beyond Energy: LCA of Organic Photovoltaic Solar Cells Michael Tsang - - PowerPoint PPT Presentation

Beyond Energy: LCA of Organic Photovoltaic Solar Cells

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avniR 2014: Life Cycle In Practice

Michael Tsang*, Guido Sonnemann, Dario Bassani

*PhD Candidate Université de Bordeaux | michael.tsang@u-bordeaux.fr

Outline

• Photovoltaics
• Organic Photovoltaics
• LCA: Methods
• LCA: Results
• Sensitivity Analysis
• Comparison to Conventional Cells
• Conclusions

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Photovoltaics

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• General PV Technology:

conversion of light energy to electrical energy

– Semiconductor absorbs light, ‘‘knocking’’ loose electrons which create electricity (in a circuit)

Photo Credits: www.solarcell.net

Organic Photovoltaics

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• Third generation solar technology, organic

materials act as semiconductor

Photo Credits: www.phys.org

Organic Photovoltaics

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5 10 15 20 25 30 35 Literature

Energy (MJ) Garcia-Valverde (Glass) Roes et al (Glass) Espinosa et al 2011 (PET) Espinosa et al 2001 (PET) Anctil et al 2012 (PET) Anctil et al 2010 (PET) Roes et al (PET) Espinosa et al 2012 (PET) Dye-S (Roes et al ) CdTe (Roes et al) a-Si (Laminate) m-Si (Laminate) CIS (Roes et al)

Organic Other Thin Films

Solar Cell-Efficiencies (Research Scale) Embodied Energy of Organic and Other PV Cells

Photo Credits: NREL

Motivation for the Study

• Objective: prospective assessment of the

environmental profile of organic photovoltaics using roll-to-roll technology

• Part of a larger LCA to understand the

environmental and human health impacts from organic photovoltaics from cradle-to- grave

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LCA: Goal and Scope

• Cradle-to-Gate
• Functional Unit: 1 watt-peak

(Wp); power output under standard testing conditions

• Sensitivity Analysis
• Comparison to Conventional

Cells

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Photo Credits: gelifesciences.com

LCA: System Boundaries

• Inventory data from scientific literature, stoichiometric

calculations, and Ecoinvent

• Ecoinvent 2.2 | ReCiPe v1.0.5 Midpoint (H) | openLCA 1.4

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LCA: Results

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0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% FTO Substrate and Sputtering MoO Production P3HT Production PCBM Production LiF Production Aluminum Production Gravure Printing Annealing Lamination Other

Sensitivity Analysis

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0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 Default DCBpcbm FTOinkjet

DCBpcbm: Fullerene production using DCB as solvent in place of toluene FTOinkjet: Deposition of FTO substrate using inkjet printing in place of sputtering

Comparison to Conventional Cells

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0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 Default DCBpcbm FTOinkjet Multi-C Silicon Amorphous Silicon

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Minimum Required Lifetime

• Compared impacts of organic models to

amorphous silicon to estimate the minimum lifetime needed such that its impacts are no worse than amorphous silicon over a lifetime

• f 25 years.

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Impacts Default Minimum lifetime (yrs) DCB Minimum lifetime (yrs) FTOinkjet Minimum lifetime (yrs) terr.eco 10.3 9.8 9.4 fr.eco 7.5 6.9 6.6 met.dep 6.5 6.5 6.5

• zone.dep

5.9 4.7 4.2 fossil.dep 4.7 3.7 3.6 ced 4.5 3.3 3.1 nat.land 4.4 3.6 3.4 average 4.2 3.4 3.1 ion.rad 4.0 2.1 1.5 wat.dep 3.9 2.1 1.5 fr.eutro 3.6 2.2 1.7 climate.chg 3.5 2.6 2.4 mar.eut 3.4 2.4 2.0 mar.eco 3.0 2.8 2.6 smog 3.0 2.3 2.1 agr.land 2.6 2.0 1.7 part.matter 2.6 2.0 1.7 hum.tox 2.3 2.3 1.9 terr.acid 2.1 1.5 1.3 urban.land 1.2 1.0 0.9

Minimum Required Lifetime

Energy Payback Time

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50 100 150 200 250 300 350 400 450 500 550 600 650 0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 Default FTOink DCBpcbm Multi-C Si Amorphous Si Days Years 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0.0

24-35 days

Carbon Payback Time

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20 40 60 80 100 120 140 160 180 200 220 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 Default FTOink DCBpcbm Multi-C Si Amorphous Si Days Years

7-11 days

0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0

Conclusions and Future Work

• The results suggest that organic photovoltaics

have advantages over traditional (silicon) cells from a life cycle perspective.

• Room for continued improvement with materials

selection and solar cell fabrication options.

• Average minimum required lifetime 3.1-4.2 years.
• Energy and carbon payback times are 1-2 orders
• f magnitude lower.

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Conclusions and Future Work

• Potential exposure of nanomaterials during

production (ongoing project).

• No large scale production embodying these

production pathways exists. Important to take into account hot-spots in early stage development.

• Continue through the use and disposal phases to

understand how environmental profile changes

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Acknowledgements

• Dario Bassani and Guido Sonnemann
• Financial support of the Aquitaine Region for

the Chair on LCA at the University of Bordeaux

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Michael Tsang

Michael.tsang@u-bordeaux.fr | Tél: +33 06 66 17 63 70

CyVi, Life Cycle Group

Institute for Molecular Sciences - ISM

University of Bordeaux – UMR 5255 CNRS

351 Cours de la libération – Bât A12 33405 TALENCE cedex – France

www.ism.u-bordeaux.fr

Thank you for your attention!

References

• A. Roes, E. Alsema, K. Blok and M. Patel, “Ex-Ante Environmental and Economic Evaluation of Polymer PV,” Progress in

Photovoltaics, pp. 372-393, 2009.

• A. Anctil, C. W. Babbitt, R. P. Raffaelle et B. J. Landi, “Material and Energy Intensity of Fullerene Production,” Environmental

Science and Technology, pp. 2353-2359, 2012.

• V. Fthenakis, R. Frischnecht, M. Rugei, H. C. Kim, E. Alsema, M. Held et M. de Wild-Scholten, Methodology Guidelines on LCA
• f Photovoltaic Electricity 2nd Edition, International Energy Agency PV Power Systems Program, 2011.
• N. Espinosa, R. Garcia-Valverde, A. Urbina and F. Krebs, “A LCA of Polymer Solar Cell Modules Prepared Using Roll-to-Roll

Methods Under Ambient Conditions,” Solar Energy Materials and Solar Cells, pp. 1293-1302, 2011.

• R. Gacia-Valverde, J. Cherni and A. Urbina, “LCA of Organic Photovoltaic Technologies,” Progress in Photovoltaics, pp. 535-

558, 2010.

• F. Krebs, "Roll to Roll Fabrication of Monolithic Large Area Polymer Solar Cells Free from Indium Tin Oxide," Solar Energy

Materials and Solar Cells, pp. 1636-1641, 2009. 20