NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by 

Supply Chain Dyn

Tellurium (Te), In

and Gallium (Ga) 

Context of PV Mo

Manufacturing C

NREL Colorado School of Strategic Energy Analysis Center Division of Mineral and Michael Woodhouse Martin LokancAlan Goodrich Rod EggertTed L. JamesRobert Margolis NREL/PR‐6A20‐57138SEMI 2012 Strategic Materials ConferOctober 23, 2012
Analysis Disclaimer

DISCLAIMER AGREEMENT

These manufacturing cost model results (Data) are provided by the National Renewable E

which is operated by the Alliance for Sustainable Energy LLC (Alliance) for the U.S. De

It is recognized that disclosure of these Data are provided under the following conditions 

Data have been prepared for reference purposes only; (2) these Data consist of forec

assumptions made on a best‐efforts basis, based upon present expectations; and (3) with existing information and are subject to change without notice.

The names DOE/NREL/ALLIANCE shall not be used in any representation, advertising, pub

whatsoever to endorse or promote any entity that adopts or uses these Data. DOE/N

provide any support, consulting, training, or assistance of any kind with regard to the 

updates, revisions, or new versions of these Data.

YOU AGREE TO INDEMNIFY DOE/NREL/ALLIANCE AND ITS AFFILIATES, OFFICERS, AGENTS, 

ANY CLAIM OR DEMAND, INCLUDING REASONABLE ATTORNEYS' FEES, RELATED TO Y

ADOPTION OF THESE DATA FOR ANY PURPOSE WHATSOEVER. THESE DATA ARE PROV

DOE/NREL/ALLIANCE "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDIN

THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR P

DISCLAIMED. IN NO EVENT SHALL DOE/NREL/ALLIANCE BE LIABLE FOR ANY SPECIAL, 

CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER, INCLUDING BUT NOT 

ASSOCIATED WITH THE LOSS OF DATA OR PROFITS, WHICH MAY RESULT FROM AN AC

NEGLIGENCE, OR OTHER TORTIOUS CLAIM THAT ARISES OUT OF OR IN CONNECTION 

PERFORMANCE OF THESE DATA.
Recent Publications on This Topic

Publication accepted by the Journal of Photovoltaics.
IA = d    

10-3  

What is the material intensity (I, in metric tonnes p

using an element within a layer in a PV module?

Where:

d = Layer thickness (in m)

 = Layer density (in g.cm‐3)

XA = The mass fraction of element A

within the layer

 = The area‐based module power

rating (in W/ m2)

UA = The utilization of element A in

manufacturing, representing the

fraction of the original amount of

A that is actually captured within

the completed module

RA = The recovery fraction of element

A in manufacturing,

representing the initial amount

of A that can be reused after the

appropriate deposition on the

module and after the

appropriate recovery steps.
The sensitivity of PV module manufacturing costs

to the price for the element’s precursor

PA = Price of the element at a standard grade of purity 

T = Tolling charge to refine the element to ‘solar grade’ 

meld it into its appropriate precursor for manufact

XY = Weight percentage of A in the precursor compound

(0.53 for CdTe, 1 for In and Ga in CIGS and HVPE GaAs, 0

RA = Net recovery fraction of A from the manufacturing 

after the appropriate deposition and recovery pro

RVA = Recovery value of A ($/ kg).

CA+T ($/Wp ) = IA 106 PA  T  (RA  RV

XY (1 - RA )  
Tellurium in Single‐Junction Polycrysta

Material co

byproduct recov

IA = d 

10

CA+T ($/Wp ) = 

BEST-EFFORTS ANALYSIS OF THE MATERIAL INTENSITY FOR 

TELLURIUM IN CdTe. 2012 BASELINE. 

Element A of interest d 



(g.cm-3) XA  (W.m-2) 

UA IA

(MT/ GW) 

PA & T CA+T

RA

Te in CdTe 2.5 m 

[1, 2] 

5.85 

[3] 0.53 128 [4] 

0.70 [5] 

69 

 PTe

≈ $150/ kg 

[6] 

TCdTe

≈ $110/ kg 

[7] 

$0.034/ W 

0.20 [5] 

Estimated 2011 Material Supply Base for Tellurium 

Primary annual production from Cu byproduct recovery 

500 - 600 MT [8]

Notes and References: 

The element prices shown are rough estimates from a relevant industry collaborator. The exact pricing terms for any material supply contract, and the duration of delivery, are highly guarded and need to be considered on a case-by-case basis. 
IA = d    XA 10-3  UA   1 - RA

Indium in Cu[In(1‐x)Gax]ySe2, or ‘CIG

CA+T ($/Wp ) = IA 106 PA  

 

BEST-EFFORTS ANALYSIS OF THE MATERIAL INTENSITY F

INDIUM IN CIGS. 2012 BASELINE. 

Element A of interest d 



(g.cm-3) XA



(W.m2) 

UA IA

(MT/ GW) 

PA & T 

RA

In in CIGS 2.0 m [9] 5.75 [10] ≈ 0.221 [9, 11] 157 [4, 12] 

0.552

23 

 PIn

≈ $520/ kg 

[13] 

TIn

≈ $100/ kg

0.25 

Estimated 2011 Material Supply Base for Indium 

Primary annual production from Zn byproduct recovery 

550 - 650 MT [20, 21]

Notes and References: 

The element prices shown are rough estimates from a relevant industry collaborator. The exact pricing terms for any material su

the duration of delivery, are highly guarded and need to be considered on a case-by-case basis. 

1Representative weight percentage, calculated from the CIGS stoichiometry within the given references. 2 For sputtering, the target material utilization for a rotary target is around 75%, while the material utilization of a planar target is ar

 30%. The net fraction of material that is then captured within the module is then the product of this material utilization and the t efficiency. The value shown here is the product of these two for a rotary target, and is also a representative collection fraction fo the co-evaporation approach to CIGS module manufacturing. 

3 This will very much depend upon the chosen form factor, and rotatable targets are generally more expensive than planar targets. T

 material on a spent sputtering or evaporation target can usually be resold—in consultation with a CIGS manufacturing firm we a the remaining material on a used rotary target could be resold with a typical reclamation value of around 25% of the original valu
BEST-EFFORTS ANALYSIS OF THE MATERIAL INTENSITY F

INDIUM IN CIGS. 2012 BASELINE. 

Element A of interest d 



(g.cm-3) X

A



(W.

m2) 

U

A

I

A

(MT/ GW) 

P

A & T 

RA

In in CIGS 2.0 

m 

[9] 

5.75 

[10] 

≈ 0.221

[9, 11] 

157 

[4, 12] 

0.552

23 

 PIn

≈ $520/ kg 

[13] 

TIn

≈ $100/ kg

0.25 

Estimated 2011 Material Supply Base for Indium 

Primary annual production from Zn byproduct recovery 

550 - 650 MT [20, 21]

Notes and References: 

The element prices shown are rough estimates from a relevant industry collaborator. The exact pricing terms for any material su

the duration of delivery, are highly guarded and need to be considered on a case-by-case basis. 

1Representative weight percentage, calculated from the CIGS stoichiometry within the given references. 2 For sputtering, the target material utilization for a rotary target is around 75%, while the material utilization of a planar target is ar

 30%. The net fraction of material that is then captured within the module is then the product of this material utilization and the t efficiency. The value shown here is the product of these two for a rotary target, and is also a representative collection fraction fo the co-evaporation approach to CIGS module manufacturing. 

3 This will very much depend upon the chosen form factor, and rotatable targets are generally more expensive than planar targets. T

 material on a spent sputtering or evaporation target can usually be resold—in consultation with a CIGS manufacturing firm we a the remaining material on a used rotary target could be resold with a typical reclamation value of around 25% of the original valu

IA = d 





 X

A

10-3 

U

A

  1 - R

A

Indium in Cu[In(1

‐x)Ga

x

]

ySe

2

, or ‘CIG

CA+T ($/Wp ) = IA 106

PA



 

Material constraint if relyin

recovery at present e

≈ 650/ 23

28 GW
Gallium in Cu[In(1‐x)Gax]ySe2, or ‘CI

IA = d    XA 10-3  UA   1 - RA CA+T ($/Wp ) = IA 106 P

 

BEST-EFFORTS ANALYSIS OF THE MATERIAL INTENSITY AND 

GALLIUM IN CIGS. 2012 BASELINE. 

Element A of interest d 



(g.cm-3) XA



(W.m2) 

UA IA

(MT/ GW) 

PA & T 

RA

In in CIGS 2.0 m [9] 5.75 [10] ≈ 0.071 [9, 11] 157 [4, 12] 

0.552

7.5 

 PGa

≈ $400/ 

[14] 

TIn

≈ $100/ k

0.254

Estimated 2011 Material Supply Base for Gallium 

Primary annual production from Bauxite (Al) byproduct recovery 

250 – 300 MT [22, 23] 

Notes and References: 

The element prices shown are rough estimates from a relevant industry collaborator. The exact pricing terms for any material 

the duration of delivery, are highly guarded and need to be considered on a case-by-case basis. 

1Representative weight percentage, calculated from the CIGS stoichiometry within the given references. 2 For sputtering, the target material utilization for a rotary target is around 80%, while the material utilization of a planar target is 

 30%. The net fraction of material that is then captured within the module is then the product of this material utilization and the 

 efficiency. The value shown here is the product of these two for a rotary target, and is also a representative collection fraction  the co-evaporation approach to CIGS module manufacturing. 

3 This will very much depend upon the chosen form factor, and rotatable targets are generally more expensive than planar targets. 

 material on a spent sputtering or evaporation target can usually be resold—in consultation with a CIGS manufacturing firm we 

 the remaining material on a used rotary target could be resold with a typical reclamation value of around 25% of the original v

4 This may be deposited from a Cu-Ga composite target if sputtering. 
BEST-EFFORTS ANALYSIS OF THE MATERIAL INTENSITY AND 

GALLIUM IN CIGS. 2012 BASELINE. 

Element A of interest d 



(g.cm-3) X

A



(W.

m2) 

U

A

I

A

(MT/ GW) 

P

A & T 

RA

In in CIGS 2.0 

m 

[9] 

5.75 

[10] 

≈ 0.071

[9, 11] 

157 

[4, 12] 

0.552

7.5 

 PGa

≈ $400/ 

[14] 

TIn

≈ $100/ k

0.254

Estimated 2011 Material Supply Base for Gallium 

Primary annual production from Bauxite (Al) byproduct recovery 

250 – 300 MT [22, 23] 

Notes and References: 

The element prices shown are rough estimates from a relevant industry collaborator. The exact pricing terms for any material 

the duration of delivery, are highly guarded and need to be considered on a case-by-case basis. 1Representative weight percentage, calculated from the CIGS stoichiometry within the given references. 

2 For sputtering, the target material utilization for a rotary target is around 80%, while the material utilization of a planar target is 

 30%. The net fraction of material that is then captured within the module is then the product of this material utilization and the 

 efficiency. The value shown here is the product of these two for a rotary target, and is also a representative collection fraction  the co-evaporation approach to CIGS module manufacturing. 

3 This will very much depend upon the chosen form factor, and rotatable targets are generally more expensive than planar targets. 

 material on a spent sputtering or evaporation target can usually be resold—in consultation with a CIGS manufacturing firm we 

 the remaining material on a used rotary target could be resold with a typical reclamation value of around 25% of the original v

4 This may be deposited from a Cu-Ga composite target if sputtering. 

Gallium in Cu[In(1

‐x)Ga

x

]

ySe

2

, or ‘CI

IA = d 





 X

A

10-3 

U

A

  1 - R

A

CA+T ($/Wp ) = IA 106

P

 

Material constra

byproduct recovery a

≈ 300

40 
BEST-EFFORTS ANALYSIS OF THE MATERIAL INTENSITY AND COST CON

FOR GALLIUM IN SINGLE-JUNCTION GaAs. 2012 BASELINE. 

Element A of interest 

d  (g.cm-3) XA  (W.m-2)

UA IA

(MT/ GW) 

PA & 

RA

Ga in Single-Junction 

GaAs (MOCVD) 

2.5 m 

[15-17] 

5.32 

[18] 0.48 235 [19]

0.30 

91 

PG

≈ $400

[14

TTM

≈ $210

0.005

Ga in Single-Junction 

GaAs (HVPE) 

2.5 m 5.32 

[18] 0.48 2357

0.30 

91 

P

≈ $400

[14

TG

≈ $100

0.005

Estimated 2011 Material Supply Base for Gallium 

Primary annual production from Bauxite (Al) byproduct recovery 

250 – 300 MT [22, 23] 

Notes and References: 

The champion module efficiencies shown in this table are taken from Table II in reference [19]. The efficiencies are  independently-verified, but not all of the modules represented are produced and sold at GW–or even MW—levels of s

The element prices shown are rough estimates. The exact pricing terms for any material supply contract, and the duration o delivery, are highly guarded and need to be considered on a case-by-case basis. 

5 It is our understanding that Ga is not currently recovered from the MOCVD and HVPE processes for depositing GaAs, but th

 than likely due to the fact that these are currently just research-level investigations.

6 Estimated price of around $2500/ kg for large volume purchasing contracts of Ga(CH3)3, provided by a relevant major supplie

7 This module efficiency has not been demonstrated and is used for illustrative purposes only. An HVPE GaAs cell efficiency 

 has been reported in reference [24]. 

Gallium in Single‐Junction GaAs

IA = d    XA 10-3  UA   1 - RA CA+T ($/Wp ) = IA 106 

 
BEST-EFFORTS ANALYSIS OF THE MATERIAL INTENSITY AND COST CON

FOR GALLIUM IN SINGLE-JUNCTION GaAs. 2012 BASELINE. 

Element A of interest 

d  (g.cm-3) XA  (W.m-2)

UA IA

(MT/ GW) 

PA & 

RA

Ga in Single-Junction 

GaAs (MOCVD) 

2.5 m 

[15-17] 

5.32 

[18] 0.48 235 [19]

0.30 

91 

PG

≈ $400

[14

TTM

≈ $210

0.005

Ga in Single-Junction 

GaAs (HVPE) 

2.5 m 5.32 

[18] 0.48 2357

0.30 

91 

P

≈ $400

[14

TG

≈ $100

0.005

Estimated 2011 Material Supply Base for Gallium 

Primary annual production from Bauxite (Al) byproduct recovery 

250 – 300 MT [22, 23] 

Notes and References: 

The champion module efficiencies shown in this table are taken from Table II in reference [19]. The efficiencies are  independently-verified, but not all of the modules represented are produced and sold at GW–or even MW—levels of s

The element prices shown are rough estimates. The exact pricing terms for any material supply contract, and the duration o delivery, are highly guarded and need to be considered on a case-by-case basis. 

5 It is our understanding that Ga is not currently recovered from the MOCVD and HVPE processes for depositing GaAs, but th

 than likely due to the fact that these are currently just research-level investigations.

6 Estimated price of around $2500/ kg for large volume purchasing contracts of Ga(CH3)3, provided by a relevant major supplie

7 This module efficiency has not been demonstrated and is used for illustrative purposes only. An HVPE GaAs cell efficiency 

 has been reported in reference [24]. 

Gallium in Single‐Junction GaAs

IA = d    XA 10-3  UA   1 - RA CA+T ($/Wp ) = IA 106 

 

Material constraint if relyin

recovery at present 

≈ 300/ 91

3 ‐ 4 GW
Are these energy‐significant levels of de

Projected trendconsumption: ≈

Pre‐Industrial CO

Carbon‐free pow

efficiency) in 20

≈10 TW

In 2050 to keep 

WRE= Wigley, R

Source: Hoffert et al. (1998). Nature, 395, 881.

CO2 

Concentra 

(ppm

445‐49490‐53535‐59590‐71710‐85

855‐11

(Table 3.5 in 
Is there a precedent for a predicament such 

Edwin Drake

George Bissel

Titusville, Pennsylvania (1859)
How did the thinking evolve?
Source: Hubbert, M.K. (1956). Shell Oil Development Company, Publication 95.

How did the thinking evolve?
How did it actually play out?

Source

Source: Hubbert, M.K. (1956). Shell Oil Development Company,

Publication 95.
Getting to the fundamental question

From R 

“Depletion and 

Petroleum 

The Energy Journ
I

A = 

d 





 X

A

10-3 

U

A

  1 - R

A

CA+T ($/Wp ) = 

I

A

10

6

PA



T

 (R

A

 RVA

)

X

Y (1 - R

A

)

 



The fundamental supply question for these energy

‐cr

From Woodhouse, M.; G

James, T.; Lokanc, M.; E

Dynamics of Te, In, and G

PV Module Manufacturin

Journal of P

Bc 

Be(

InmeRo

Me

0

500

1,0001,5002,0002,5003,000

8

81

153

226

298

371

444

516

589

661

734

807

879

952

1,024

1,097

1,170

1,242

1,315

1,387

1,460

1,533

1,605

1,678

1,750

1,823

1,896

1,968

2,041

2,113

2,186

2,259

2,331

2,404

Cost: $/kg metal produced

Annual output

Critical Element Supply Curve

Deposit 1 Deposit 100+ 

(MT) 

Illustration of a Critical Element Supply Curve 

Annual Output (MT) 

Cost ($/ kg) of element recovery 
Potential improvements in the material intensity for 

leads to an ability to absorb potential price increase

BEST-CASE MATERIAL INTENSITIES FOR THESE ENERGY CRITICAL ELAND COST CALCULATIONS WITH 2012 METAL PRICES 

Element A of 

interest d 



(g.cm-3) 

XA



(W.m-2)

UA 

(RA = 0) 

IA

(MT/ GW) 

CA+T 

(With 2012 

PA & T) 

Te in CdTe 1.0 m 5.85 0.53 180 1.0 17 $0.0083/ W 

In in CIGS 1.0 m 5.75 ≈ 0.22 200 1.0 6.3 $0.0049/ W 

Ga in CIGS 1.0 m 5.75 ≈ 0.07 200 1.0 2.0 $0.0013/ W 

Ga in SingleJunction 

GaAs 

(MOCVD) 

1.0 m 5.32 0.48 250 1.0 10. $0.041/ W 

Ga in SingleJunction 

GaAs (HVPE) 

1.0 m 5.32 0.48 250 1.0 10. $0.005/ W 

Estimated 2011 Material Supply Base 

(Primary annual production levels from byproduct recovery, predominantly Cu (Te), Zn (In), and Bauxite (G

Tellurium: 500 - 600 MT [8], Indium: 550 – 650 MT [20, 21], Gallium: 250 - 300 MT [22

Notes: CdTe and CIGS assumptions are based upon predicted full-potential module efficactive layer thicknesses, for the case of single-junction polycrystalline modules in commercial production. 
The fundamental supply question for these energy

‐cr

I

A = 

d 





 X

A

10-3 

U

A

  1 - R

A

CA+T ($/Wp ) = 

I

A

10

6

PA



T

 (R

A

 RVA

)

X

Y (1 - R

A

)

 



From Woodhouse, M.; G

James, T.; Lokanc, M.; E

Dynamics of Te, In, and G

PV Module Manufacturin

Journal of P

Auwit

0

500

1,0001,5002,0002,5003,000

8

81

153

226

298

371

444

516

589

661

734

807

879

952

1,024

1,097

1,170

1,242

1,315

1,387

1,460

1,533

1,605

1,678

1,750

1,823

1,896

1,968

2,041

2,113

2,186

2,259

2,331

2,404

Cost: $/kg metal produced

Annual output

Critical Element Supply Curve

Deposit 1 Deposit 100+ 

(MT) 

Illustration of a Critical Element Supply Curve 

Annual Output (MT) 

Cost ($/ kg) of element recovery 
Concluding Thoughts

[1] At present recovery efficiencies, the primary production of Telluriu

Indium from Zinc, and Gallium from bauxite is not enough to suppo

significant levels of PV.

[2] At metal prices typical for 2011, the contribution of each critical ele

module manufacturing costs would have been tractable.

[3] With improvements in the net material intensity, there is also the p

PV technologies to absorb even higher element prices—perhaps ev

of magnitude for each.

[4] The ability to absorb such potential price increases leads to the pos

augmented supply base for each element.

[5] To avert potentially debilitating increases in the price for any miner

TIMING IS OF THE ESSENCE, and so it will be advantageous to

GET ENGAGED EARLY.

Corresponding Authors: michael.woodhouse@nrel.gov, alan.goodrich@
References

[1] K. Zweibel, The Impact of Tellurium Supply on Cadmium Telluride Photovoltaics, Science, 328 (2010) 699‐701.

[2] A. Gupta, V. Parikh, A.D. Compaan, High Efficiency Ultra‐Thin Sputtered CdTe Solar Cells, Solar Energy Materials and Sola

[3] CRC Handbook of Chemistry and Physics, CRC Press, Boca Raton, FL, 1986.

[4] M.A. Green, K. Emery, et. al., Solar Cell Efficiency Tables, Progress in photovoltaics: research and applications, 19 (2011) 

[5] V Fthenakis, Long‐term estimates of primary and secondary sources of thin‐film PV materials: recycling and sustainabilit

PVSC, (2010) Slide 6.

[6] Representative 2011 price from:http://www.metal‐pages.com/metals/tellurium/metal‐prices‐news‐information/.

[7] Private conversation with a major CdTe material supplier, on the condition of anonymity. September 2011.

[8] M. Woodhouse, A. Goodrich, R. Margolis, T. James, R.Dhere, T. Gessert, T. Barnes, R. Eggert, D. Albin, Perspectives on th

Photovoltaic Module Manufacturers to Address Expected Increases in the Price for Tellurium, Sol Energy Materials and 

[9] W.N. Shafarman, L. Stolt, Cu(InGa)Se2 Solar Cells, in: Handbook of photovoltaic science and engineering, A. Luque, S. Heg

West Sussex, England, 2003.

[10] D. Suri, K. Nagpal, G. Chadha, Journal of Applied Cystallography, 22 (1989) 578.

[11] R. Kamada, W.N. Shafarman, R.W. Birkmire, Cu(In,Ga)Se2 film formation from selenization of mixed metal/ metal‐selen

and Solar Cells, 94 (2010) 451‐456.

[12] http://www.miasole.com.

[13] Representative 2011 price from: http://www.metal‐pages.com/metals/indium/metal‐prices‐news‐information/.

[14] Representative 2011 price from: http://www.metal‐pages.com/metals/gallium/metal‐prices‐news‐information/.[15] G.J. Bauhuis, P. Mulder, E.J. Haverkamp, J.C.C.M. Huijben, J.J. Schermer, 26.1% thin‐film GaAs solar cells using epitaxial 

Solar Cells, 93 (2009) 1488‐1491.

[16] A.V. Geelen, P.R. Hageman, G.J. Bauhuis, P.C.v. Rijsingen, P. Schmidt, L.J. Giling, Epitaxial lift‐off of GaAs solar cell from a 

Materials Science and Engineering, (1997) 162‐171.

[17] J.J. Schermer, G.J. Bauhuis, P. Mulder, E.J. Haverkamp, J.v. Deelen, A.T.J.v. Niftrik, P.K. Larsen, Photo confinement in hig

cells obtained by epitaxial lift‐off, Thin Solid Films, (2006) 645‐653.

[18] O. Madelung, U. Rossler, M. Schulz, Table showing GaAs Debye temperature, density, heat capacity, and melting point., 

elements, II‐VI and III‐V compounds., Springer‐Verlag, 2002.

[19] M.A. Green, K. Emery, Y. Hishikawa, W. Warta, E.D. Dunlop, Solar cell efficiency tables, Progress in photovoltaics: resea

[20] C. Gowans, The Indium Corporation. Indium 101—Earth Abundant Material or Rare? (2010) Available online at: http://b

gowans/indium‐101‐earth‐abundant‐material‐or‐rare

[21] Minerals Commodity Summary: Indium, US Geological Survey and US Department of the Interior, (2011)

Available online at: http://minerals.usgs.gov/minerals/pubs/commodity/indium/

[22] D. Bauer, D. Diamond, J. Li, M. McKittrick, D.Sandalow, P. Telleen, B. Wanner, in, Critical Materials Strategy, U. S. Depar

2011. Available online at: http://energy.gov/pi/office‐policy‐and‐international‐affairs/downloads/2011‐critical‐materia

[23] Minor Metals: March 2012, The Mining Journal. Available online at: http://www.mining‐journal.com/reports/minor‐me[24] J.C.C. Fan, C.O. Bozler, R.L. Chapman, Simplified fabrication of GaAs homojunction solar cells with increased conversion 

Letters, 32 (1978) 390‐392.

[25] F. Ojebuoboh, First Solar & Supplementing Byproduct Tellurium For the Evolving CdTe Solar Market, in: Presentation to 

August 8, 2011.
Supplemental Slide: The Incumbent PV Techn

Goodrich, A.; Hacke, P.; Wang, Q.; Sopori, B.; Margolis, R.; James, T.; Woodhouse, M. “A Wafer‐Ba

Silicon Photovoltaics Road Map: Utilizing Known Technology Improvement Opportunities for Furthe

Manufacturing Costs,” accepted by Solar Energy Materials and Solar Cells.
Image Sources

Slide 11

[1] Edwin Drake: http://en.wikipedia.org/wiki/Edwin_Drake

[2] George Bissel: http://www.forbes.com/2009/09/03/oil‐daniel‐yergin‐business‐energ[3] Drilling rig in Titusville, PA, owned by the Pennsylvania Rock Oil Company:

http://en.wikipedia.org/wiki/File:First_Oil_Well.jpg

Slide 12

[4] M King Hubbert: http://mkinghubbert.wordpress.com

For a history of the development of the global petroleum industry, and additional imagesYergin, D. (2009). The Prize: The Epic Quest for Oil, Money and Power, Free P