.

National Renewable Energy Laboratory

1617 Cole Boulevard, Golden, Colorado 80401-3393 

303-275-3000 • www.nrel.gov

Operated for the U.S. Department of Energy 

Office of Energy Efficiency and Renewable Energy 

by Midwest Research Institute • Battelle 

Contract No. DE-AC36-99-GO10337 

B. von Roedern, K. Zweibel, and H.S. Ullal 

Prepared for the 31st IEEE Photovoltaics Specialists 

Conference and Exhibition 

Lake Buena Vista, Florida 

January 3–7, 2005 

February 2005 • NREL/CP-520-37353 

The Role of Polycrystalline 

Thin-Film PV Technologies for 

Achieving Mid-Term MarketCompetitive PV Modules 
NOTICE 

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THE ROLE OF POLYCRYSTALLINE THIN-FILM PV TECHNOLOGIES 

FOR ACHIEVING MID-TERM MARKET-COMPETITIVE PV MODULES

B. von Roedern, K. Zweibel, and H.S. Ullal 

National Center for Photovoltaics 

National Renewable Energy Laboratory (NREL) 

1617 Cole Boulevard 

Golden, CO 80401-3393 USA

Tel: (303) 384 6480; Fax: (303) 384 6430; E-mail: bolko_von_roedern@nrel.gov 

ABSTRACT

This paper reviews the current commercial status of

CuInSe2 alloys (collectively, CIS) and CdTe-based

photovoltaic (PV) modules, comparing the performance of

commercial products with the results achieved for solar

cell and prototype module champions. We provide an

update for these PV cell and module technologies, and

also compare CIS and CdTe performance levels to the

results achieved by the crystalline Si PV industry. This 

comparison shows that CIS and CdTe module technology

presently offers the best (and perhaps only) approach for

significantly exceeding the cost/performance levels

established by crystalline Si PV technologies. A semiempirical methodology is used for comparing “champion”

solar cell and prototype module data with performance

achieved on manufacturing lines. Using a conservative

assumption that thin-film technologies will eliminate the

40% of PV module costs arising from the Si wafer or

ribbon, we estimate the future performance of all

established PV module candidates, and conclude that, 

based on 2004 knowledge about each PV technology, CIS

and CdTe should provide cost-competitive advantages

over crystalline Si. 

INTRODUCTION 

Figure 1 shows the best verified champion cell

performance achieved in each of the thin-film PV 

technologies. Table 1 shows champion large-area

modules produced by a number of entities. Note that 

aperture-area efficiencies are reported in this table, 

whereas commercial efficiencies listed below use total

module-area efficiency values. This paper will provide a

measure for estimating mid-term commercial product 

performance based on demonstrated and verified

champion cell efficiency values. 

TECHNOLOGY — DRIVER FOR PERFORMANCE 

After investing in a commercial manufacturing line, 

two pathways lead to increased performance of the

manufactured product. The first approach is to optimize

the chosen process for optimum performance and yield. 

Once an optimum has been obtained in this manner, one

has to decide which aspects of the manufacturing process

should be upgraded to ensure further increases in module

performance. Because such upgrades often require

massive capital investment and “downtime” (i.e., loss of 

The Best One-of-a-Kind Laboratory 

Cell Efficiencies for Thin Films

(Standard Conditions)

Efficiency (

%)

CuInSe2

CdTe

Amorphous silicon 

(stabilized)

Univ. of Maine

Boeing

Boeing

Boeing

Boeing

ARCO

AMETEK

NREL

Boeing

EuroCIS

Univ. of So. Florida

Univ. of So. FL

BP Solar

Kodak

Kodak Monosolar

Matsushita

12

8

4

0

1975 1980 1985 1990 1995 2000

United Solar

16

20

NREL

2005

RCA

ECD

NREL

Photon Energy

Fig. 1: Development of “champion” solar cell efficiencies. The progress made from about 1980 to 026587181

2000 is significant.

1 
Table 1: Best Large-Area, Thin-Film Modules

(standard conditions, aperture-area)

Company Device Aperture 

Area (cm2

) 

Efficiency (%) Power (W) Date 

Würth Solar CIGS 6500 13.0 84.6 06/04 

First Solar CdTe 6623 10.2* 67.5* 02/04 

Shell Solar GmbH CIGSS 4938 13.1 64.8 05/03 

Global Solar CIGS 7085 10.1* 71.2* 09/04 

Antec Solar CdTe 6633 7.3 52.3 06/04 

Shell Solar CIGSS 3626 12.8* 46.5* 03/03 

Showa Shell CIGS 3600 12.8 44.15 05/03 

Revised 09/04 * NREL Confirmed 

manufacturing capacity), it is important that the

upgrades will deliver the expected performance 

improvement. It appears that during the most recent 

years, the activities of the Thin Film Partnership’s

Technology Partners (Shell Solar – CIS, Global Solar –

CIS, EPV – CIS, and First Solar – CdTe) focused on

achieving progress via the first approach, optimizing for

high yield and high performance while maintaining a

chosen process. Significant progress was made,

resulting in several megawatts of modules being sold 

(see Table 1 for “champion” module and Table 2 for

commercial module performance). 

To further boost its sales for power generation 

applications, Shell Solar announced development of an

80-W CIS module to better compete with crystalline Si

modules that today have power ratings ≥55 W. EPV

and ISET were qualifying and improving their new CIS

deposition schemes (using “hybrid” vacuum deposition 

or nano-particle precursors, respectively). At the same

time, NREL, through further adjustments to its 

established “3-stage” deposition process, achieved a

new champion cell with an efficiency of 19.5%, slightly

bettering the previous 19.3% record [1]. 

In 2004, First Solar established a “generation 2”

manufacturing line that eliminates previous bottlenecks

in module throughput. The new line is designed for

producing 25 MW of CdTe modules annually and 

expected to be in full operation in 2005. Dr. Wu et. al. 

from NREL demonstrated the performance

enhancements from using cadmium stannate (Cd2SnO4) 

transparent conductive oxide electrodes, in conjunction

with tin zinc oxide (ZnSnOx) buffer layers. Using these, 

the 16.5%-efficient champion CdTe cell was previously

prepared [2]. New buffer layers were also evaluated in

conjunction with commercially produced SnO2

transparent conductive electrodes, demonstrating

superior performance [3]. These processes appear to

be the next logical step for implementation into

manufacturing.

An important aspect of CdTe PV technology is to

ensure long-term stability. Experimentally, cells or

coupons from modules are tested, usually under 1-sun

intensity illumination and open-circuit voltage conditions 

and a device temperature of about 65oC for thousands 

of hours. Degradation is typically observed to “stabilize” 

and can be minimized (in a few circumstances, there is

no degradation, or even an improvement in performance

after stressing), through optimized processing. 

Presently, it is not always clear to what degree changes

in the device stability are due to details in cell design

and to what degree effects like corrosion are the cause

for degradation. However, published work by the

Colorado State University group and unpublished work

from First Solar have revealed that the details of the 

CdCl2 treatment, essential for achieving good device

performance, can indeed significantly affect the amount

of observed degradation [4]. Until better understood, 

each change in cell or module process must also be

evaluated for long-term stability. Past work has often

focused on eliminating the Cu “doping” that is applied

with many back-contacting recipes. However, recent 

work may suggest that rather than eliminating the Cucontent of the back contact, it may be more important to

incorporate Cu in such a way as to not cause a stability 

problem [5]. CIS technology continues to experience

“transients,” i.e., after exposure of the modules to

elevated temperatures in the dark, which happens to be

the condition during the final module lamination process,

module power may drop by up to ~20%, but this loss is

restored with subsequent illumination during exposure

[6], and has not been observed to lead to degradation in

long-term outdoor exposure experiments. 

The Thin Film Partnership has also initiated a

program that investigates module reliability, durability,

and module packaging (encapsulation) issues. This

work is useful for identifying manufacturing defects

arising from the module wiring and “package,” and is

now considered required to gain confidence that longterm performance can be guaranteed. 

2 
Table 2: Module Efficien d “Performance Ratios”

Eff. Module Temp. Coeff. 

P/oC)

Technology Performance

cham oduc

cy from Survey of Manufacturers’ Websites an

(%) (% Ratio pion cell-pr t

16.9 SunPower SPR210 na (‘low’) , sp. j. 16.9/24.7[7]=

68% 

FZ-Si

16.1 Sanyo HIP190BA .33 -Si, “HIT” j. 7[7]=

65% 

2 -0 CZ 16.1/24.

14.3 BP7180 -0.5 CZ-Si, sp. j. 14.3/24.7[7]=

58% 

13.3 Kyocera KC187G OC=-0.12 MC-Si, s.p. 13.3/21.2[8]=

63% 

V

13.3 Shell Ultra175-P -0.43 CZ-Si, s.p. 13.3/21.2[8]= 63% 

13.0 RWESchott A

300-DGF/315 

47 G (ribbon) 

s.p.

SE- -0. EF 13.0/21.2[8]=

Si, 61% 

12.8 Sharp ND-167-U1 na MC-Si, s.p. 12.8/21.2[8]= 60% 

11.5 GEPV-165M (up to)-0.5 CZ-Si (Reclaimed), 

.p.

11.5/21.2[8]=

s 54% 

11.0 WürthSolar 

WS31050/80 

-0.36 CIGS 11.0/19.5[1]=

56% 

 9.4 Shell Solar ST-40 -0.6 CIGSS 9.4%/19.5[1]=

48% 

 7.6 First Solar FS55 -0.25 CdTe 7.6/16.5[2]= 

46% 

 6.4 Mitsubishi Heavy 

MA100 

-0.2 a

s

-Si,

ingle-junction 

6.4/10.0[9]=

64% 

 6.3 Uni-Solar US-64 (-0.21) a-Si, 

triple-junction 

6.7/12.1[7]=

52% 

s.p. = “standard” diffused junction screen printed cells; s

l

ay compete with

th

th

W

cu

cu

te

W

va

es

ance

 and R

ce r

p.j. = cells employing alternative junctions (“HIT,” 

e mainstream crystalline Si products. The first input to

is method is derived from a survey of manufacturers’

eb sites (shown in Table 2). 

In column 5 of Table 2, we show the ratio of the

rrent commercial performance (column 1 value) to the 

rrent champion cell performance of the respective PV

chnology, referring to such a relationship as c/c ratio.

e note that the c/c ratio for various PV technologies

ries between 46% and 68%. There seems to be a trend

tablished that with manufacturing maturity the c/c ratio 

 of Commercial Modules Made With Different PV 

elative Cost Performance

ating 

s.p.

Relative cost divided by relative

performance (about proportional to 

future $/W

point contacts, buried laser grooves) 

PROJECTIONS OF FUTURE PERFORMANCE

A pragmatic method was developed for predicting future

performance and potential market impact of al

technologies.We sought to avoid comparing favorable

projections for one PV technology with less favorable

projections of another one. The method relies on

comparing 2004 commercial product efficiency data with

2004 laboratory solar cell champion data to assess how

thin-film PV technologies in the future m

Table 3: Projected Future Commercial Perform

Technologies, and Their Relative Performance

Technology Future commercial

module efficiency,

based on 2004

technology

knowledge (%)

Relative

performan

(Standard,

silicon = 1) 

p module cost 

differences with standard 

crystalline Si) assuming 40% thinfilm module cost advantage 

Silicon (sp. j.) 19.8 1.18 0.85 (highly competitive) 

Silicon (s.p.) 17.0 1.00 1.00 

CIGS 15.6 0.92 0.65 (highly competitive) 

CdTe 13.2 0.78 0.77 (highly competitive) 

a-Si (1-j) 8.0 0.47 1.28 (not competitive) 

a-Si (3-j) 9.7 0.57 1.05 (about the same) 

s.p. = “standard” diffused junction screen-printed cells; sp. j. = ns (“HIT,” 

point contacts, buried laser grooves)

 cells employing alternative junctio

3 
gradually i

ell improvements become harder, and (2) module

efficienc av catch up. fo

crystallin , values >70% have not ined.

Based o e a of 80%

will likely re tim st futur

commer od se ampion ce

perform kn in 3, we lis

expected future ial product p ance base

on today m performance a c/c ratio o

80%. In ti duct p nce t

improve a lues cturin

process o e of our curren

best es o i atur

process a n hav

been implement cturing. This methodolog

can be de ion cel

perform is n r commercia

product- he cc bee

established. 

The compa lms and crystalline Si PV

technolo fu y th t that it is no

clear what market share different Si technologies will

attain in fut Si PV nology” wa

usually br n do able 

2 reveals, the l, cast ingo

ribbon) h s regarding th

perform of al pr ther, wha

matters is hether th ad entiona

ing (

ont ctin

esi at ive junctionrma

nes are 

dTe-based

are com

eved

able 1. T ys

also look v e, s

is being made. The third

module performance ratio,

standard (s.p.) crystalline Si y.

column in this table calculat cost ratio for

these techno es a 40% advantage for

thin-film m on the edge that in a

crystalline ally 40% of the manufacturing

costs are i by manufacturin silicon wafer or

ribbon requ manufacturing th r cells. This is a

component terials cost minimized in thin-film

modules. r the thin-film nologies, relative

ost lev

erf ma wafers or

ed on a

ratio of $/Wp module manufacturing cost. That is, the 

in the should be approximately 

proportional to een the

gy opt standard crystalline Si 

ogy. 

40% fi ilms may be conservative,

lculation estimates suggest it could

igh as 6 ses where thin-film capital

re alrea for CdTe or some thirdon thin n easily recalculate

ojected c ing a different coste perce ir own cost estimates.

ances (e.g., adding some cost

advantage to her performance sp.j. crystalline Si 

ch; or a on cell efficiency 

ement wi technology than such

c r technologies). One of the 

possible strengt approach is to figuratively wash

r hands of -order perturbations and

assume that the average out. Thus, we are able to

a single fina e 3, far right column) with

which to compare vastly different technologies. 

Table 3 su sed on today’s technology

and manu w-how, future CIS and CdTe

mo able to compete with future 

ystalline Si ven if crystalline silicon

y su ansitions to higher cell

unction

on its

special value in the building-integrated PV (BIPV) 

a

cts, low performance may

constitute som

. cted that

eed

ncies)

will be suc and

somewhat

Althou line Si field have a

uantitative om standard 

creen-prin h-efficiency specialnction de not yet available for

ost thin- velopment of a better 

umerical le to predict with much

layer,

deposition process, or process optimization will contribute

ncreases, presumably because (1) champion ribbons eliminated, enabling a comparison bas

c

ies h e time to However, even r number

e Si yet been obta

n thes

be a

trends, we assume th

asonable figure to es

t a c/c-ratio

ate the be e

technolo

technol

cial m

ance

ule performance ba

own today. Thus,

d on ch

Table

ll

t The

commerc

pion cell

erform

and

d 

f

since ca

’s cha be as h

 prac

 gradu

ce, we expect pro

lly from today’s va

erforma

 as manufa

o

g

costs a

generati

es are

timate

ptimized. A valu

f what could be ach

80% is

eved for a m

t

e

the pr

advantag

after dvanced process co

ed into manufa

trol schemes e Other nu

y dis

upgra

ance

d in the future once 

obtained, or whe

new champ

bette

l

lapproa

enhanc

based values for t ratios have n progress may o

rison of thin fi

gy is rther complicated b e fac t get

the

oke

ure. In the past,

wn by type of Si substrate. 

“tech

But, as T

s

Si wafer type (single-c

ulted in little differentia

rysta

tion

t, status 

as re e thin-film PV

ance

w

today’s commerci

e cells are m

oduct; ra

e by conv

t cr

l technolog

process diffusing an emitter and collector and

c a g the emitter with screen-printed finger grids,

efficiencies using cells manufactured with special-j

schemes. The future of a-Si may depend more

d gn ed as ‘s.p.’ in column 4) or by alternat

fo tion processes currently used only for limited product

li [10]. The latter “special junction” technologies

designated as ‘sp. j.’ in column 4 of Table 2. We express

today’s commercial performance as a ratio of today’s

champion cell performance for each specific technology,

given in the last column of Table 2. 

In the second column of Table 3, we estimate future

commercial performance based on today’s cell champion

performance, assuming a c/c ratio of 80% for all

technologies. These efficiency values of future CIS- and 

C modules appear very reasonable when they

pared to aperture-area efficiencies already

mainstream power module PV markets. We believe that

our analysis is valid for standard modules sold as

achi

T

for one-of-a-kind module prototypes shown in commodity. For BIPV produ

he projected cr

ery reasonabl

talline Si module efficie

howing that a fair com

column calculates a

using a value of 1

module technolog

es a projected

ncies 

parison modules

relative

.00 for

The last 

market con

to offset ba

logies. It assum

odules, based

 cost

knowl

Si module, typic q

ncurred g the s

ired for e sola ju

and ma m

Hence, fo tech n

c els are reduced by multiplying the relative greater confidence how much a new thin-film

p or nce by 0.6, to account for the cost of 

final column

future cost differences betw

ions and the

gure for thin f

s using existing

0% in some ca

dy low (e.g.,

films). The reader ca

ost comparison us

ntage based on the

are also possible

 the hig

ssuming that a champi

ll occur faster in one

cur in the othe

hs of our 

ou these second

y just

l number (Tabl

ggests that ba

facturing kno

dules will be

modules, e

ccessfully tr

marketplace or on issues such as silicon feedstock

availability. Third-generation thin films that might be even

less efficient may have even greater problems making a 

sizable impact. 

Lessons to be learned from this are that technology

and demonstrated cell performance remain an important

yardstick in determining commercial product potential.

Unless stable laboratory cell efficiencies >12% are

demonstrated, any existing or new thin-film PV technology 

has little chance of being a strong contributor in the 

ewhat less of a penalty than for standard

On the other hand, it can be expe

ditions (including the debit caused by the n

lance-of-systems costs with higher efficie

h that higher efficiency modules will comm

higher $/Wp prices.

gh people in the crystal

understanding of how to go fr

ted processes to hig

vices, such information is

film technologies. De

understanding to be ab

4 
to enhanced future commercial product performance 

appears desirable, albeit difficult. 

Based on performance increases observed in recent

years, and investments for new manufacturing capacity 

made or announced, we project a rapid increase in the

share of thin-film PV modules in U.S. PV module

manufacturing. From a survey and estimation of the

current manufacturers, which includes Uni-Solar making

amorphous silicon roofing laminates, the following

volumes were and are projected to be produced by U.S.-

based manufacturers of thin-film PV modules. The result is 

shown in Fig. 2.

0

5

10

15

20

25

1996 1999 2002 2005

a-Si CIS CdTe

Fig. 2: Past and projected shipment of U.S.-produced

thin film PV modules (MWp per year). 

This paper provides at top-down view on the

comparison of different PV technolo MW gies, based on the

ctu

 to allow them to be competitive with

rystalline Si. This includes presumed progress in both

his work was supported by the U.S. Department of

be submitted for publication in Prog.

Photovolt. Res. Appl. 

]

Solar Energy Conference, 

June 7-11, 2004, Paris, France, p. 1980. 

a al status of today’s commercial reality and established

R&D achievements. Another top-down approach is to use 

the PV module learning curve and to add either a new

slope or an entirely new line for thin-film technologies [11].

There are also many “bottom-up” studies on the cost of PV 

systems that have historically provided ambitious cost

projections [12, 13]. At some time in the future, top-down

and bottom-up cost estimates will have to approach each

other. Presently, the bottom-up estimates make many 

assumptions about expected performance. Only after 

high-volume manufacturing has been implemented will it

be known what performance levels can be obtained

without compromising low-cost manufacturing techniques. 

A much better quantitative understanding of how process

optimization and process changes will affect the

performance of commercial modules would shorten the 

required development periods to achieve large-scale

manufacturing of high-performance thin-film PV modules. 

CONCLUSIONS

We showed how cell and prototype module

efficiencies will likely remain important for all PV

technologies, as they will be related to commercial product 

performance in future years. 

Based on 2004 knowledge about the technologies,

the performance of CIGS and CdTe modules should be

high enough

c

thin-film and crystalline Si PV technologies. 

Reliability and customer acceptance remain

significant hurdles for thin-film PV to expand its market

share. The NREL Thin Film Partnership has begun to

address these issues as part of its programs. 

Forecasting PV costs is not an idle matter, though 

some of the issues are much debated. Much of the future

of PV as an energy-significant technology rests on

meeting very ambitious cost goals. Establishing a set of

approaches and being able to begin the process of

comparing them is useful within this debate. 

ACKNOWLEDGEMENTS 

T

Energy under Contract No. DE-AC36-99GO10337. The 

authors would like to thank the numerous engineers,

scientists, and technicians worldwide whose data have 

been included in this paper. 

REFERENCES

[1] M.A. Contreras, J. AbuShama, F. Hasoon, D. Young, 

B. Egaas, and R. Noufi, “Diode Characteristics of 

State-of-the-Art ZnO/CdS/Cu(In1-xGax)Se2 Solar

Cells,” to

[2 X. Wu, J.C. Keane, R.G. Dhere, C. DeHart, D.S.

Albin, A. Duda, T.A. Gessert, S. Asher, D.H. LKevi,

and P. Sheldon, “16.5%-Efficient CdS/CdTe

Polycrystalline Thin-Film Solar Cell, Proc. 17th

European Photovoltaic Solar Energy Conference, Oct. 

22-26, 2001, Munich, Germany, p. 995. 

[3] X. Wu,and J. Zhou, “High –efficiency CdTe Solar

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by Novel Manufacturing Process,” Proc. 19th

European Photovoltaic Solar Energy Conference,

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[4] R.A. Enzenroth, K.L. Barth, and W.S. Sampath,

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[5] X. Wu and T. Gessert, private communication and to

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[6] J.R. Sites, “Device Physics of Thin-Film Polycrystalline

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(annual subcontract report), p.16-17

[7] M.A. Green, K. Emery, D.L. King, S. Igari, and W.

Warta, “Solar Cell Efficiency Tables (version 24),”

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[8] O. Schultz, S.W. Glunz, and G.P. Willeke,

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]

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[10] B. von Roedern, “The Commercial Status of the PV

Industry in 2004 – Identifying Important and

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(preprint). 

[11] T. Surek, “Progress in U.S. Photovoltaics: Looking 

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[13] K. Zweibel, 2005 (in press), "A Future of Thin Film 

PV," in Thin Film Solar Cells: Fabrication,

Characterization and Applications, Jef Poortmans and

Vladimir Archipov (eds.), John Wiley.

[9 There are no independently confirmed stabilized

single-junction champion cell results. We used 10%

based on 8.9%–9.3% reported by S. Okamoto, A. 

Terakawa, E. Maruyama, W. Shinohara, Y.

Hishikawa, and S. Kiyama, Proc. 28th IEEE PV Spec.

Conf., 2000, p. 736, and a value of 10.4% reported for

a single-junction Ge-alloy cell by X. Deng, W. Du, X. 

Yang, and H. Povolny, Proc. NCPV and Solar

Program Review Meeting, 2003, NREL/CD-520-

33586, p. 82

B

W

2

R

M

2

6 
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2. REPORT TYPE

Conference Paper 

3. DATES COVERED (From - To)

3-7 January 2005 

5a. CONTRACT NUMBER

DE-AC36-99-GO10337 

5b. GRANT NUMBER

4. TITLE AND SUBTITLE

The Role of Polycrystalline Thin-Film PV Technologies for Achieving 

Mid-Term Market-Competitive PV Modules 

5c. PROGRAM ELEMENT NUMBER

5d. PROJECT NUMBER

NREL/CP-520-37353 

5e. TASK NUMBER

PVB55101 

6. AUTHOR(S) 

B. von Roedern, K. Zweibel, and H.S. Ullal 

5f. WORK UNIT NUMBER

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

 National Renewable Energy Laboratory 

 1617 Cole Blvd. 

 Golden, CO 80401-3393 

8. PERFORMING ORGANIZATION 

REPORT NUMBER

NREL/CP-520-37353 

10. SPONSOR/MONITOR'S ACRONYM(S)

NREL 

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

11. SPONSORING/MONITORING 

AGENCY REPORT NUMBER

12. DISTRIBUTION AVAILABILITY STATEMENT

National Technical Information Service 

U.S. Department of Commerce 

5285 Port Royal Road 

Springfield, VA 22161 

13. SUPPLEMENTARY NOTES

14. ABSTRACT (Maximum 200 Words)

This paper reviews the current commercial status of CuInSe2 alloys (collectively, CIS) and CdTe-based photovoltaic (PV) 

modules, comparing the performance of commercial products with the results achieved for solar cell and prototype 

module champions. We provide an update for these PV cell and module technologies, and also compare CIS and CdTe 

performance levels to the results achieved by the crystalline Si PV industry. This comparison shows that CIS and CdTe 

module technology presently offers the best (and perhaps only) approach for significantly exceeding the cost/ 

performance levels established by crystalline Si PV technologies. A semi-empirical methodology is used for comparing 

“champion” solar cell and prototype module data with performance achieved on manufacturing lines. Using a 

conservative assumption that thin-film technologies will eliminate the 40% of PV module costs arising from the Si wafer 

or ribbon, we estimate the future performance of all established PV module candidates, and conclude that, based on 

2004 knowledge about each PV technology, CIS and CdTe should provide cost-competitive advantages over crystalline 

Si. 

15. SUBJECT TERMS

PV; module; polycrystalline; thin film; solar cell; crystalline; performance; large-area; CIS; CdTe; cost-competitive; 

16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON 

a. REPORT 

Unclassified 

b. ABSTRACT 

Unclassified

c. THIS PAGE 

Unclassified

17. LIMITATION 

OF ABSTRACT

UL 

18. NUMBER 

OF PAGES 

19b. TELEPHONE NUMBER (Include area code)

Standard Form 298 (Rev. 8/98) 

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