PROGRESS IN PHOTOVOLTAICS: RESEARCH AND APPLICATIONS
Prog. Photovolt: Res. Appl. 2008; 16:435–440
Published online in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/pip.842

Research

SHORT COMMUNICATION

Solar Cell Efﬁciency Tables(Version 32)
Martin A. Green1*,y, Keith Emery2, Yoshihiro Hishikawa3 and Wilhelm Warta4
1

ARC Photovoltaics Centre of Excellence, University of New South Wales, Sydney, 2052, Australia
National Renewable Energy Laboratory, 1617 Cole Boulevard, Golden, CO 80401, USA
National Institute of Advanced Industrial Science and Technology (AIST), Research Center for Photovoltaics (RCPV), Central 2, Umezono 1-1-1, Tsukuba,
Ibaraki, Japan
4
Department of Solar Cells—Materials and Technology, Fraunhofer-Institute for Solar Energy Systems, Heidenhofstr. 2, D-79110 Freiburg, Germany
2
3

Consolidated tables showing an extensive listing of the highest independently conﬁrmed efﬁciencies for solar
cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new
entries since January 2008 are reviewed. Copyright # 2008 John Wiley & Sons, Ltd.
key words: solar cell efﬁciency; photovoltaic efﬁciency; energy conversion efﬁciency
Received 12 June 2008

INTRODUCTION

Results are reported for cells and modules madefrom different semiconductors and for sub-categories
Since January, 1993, ‘Progress in Photovoltaics’ has within each semiconductor grouping (e.g. crystalline,
published six monthly listings of the highest conﬁrmed polycrystalline and thin ﬁlm).
efﬁciencies for a range of photovoltaic cell and module
technologies.1–3 By providing guidelines for the
inclusion of results into these tables, this not only NEW RESULTS
provides an authoritative summary of the current stateof the art but also encourages researchers to seek Highest conﬁrmed cell and module results are reported
independent conﬁrmation of results and to report in Tables I, II and IV. Any changes in the tables fromresults on a standardised basis. In the present paper, those previously published3 are set in bold type. In
new results since January 2008 are brieﬂy reviewed. most cases, a literature reference is provided that
The most important criterion for inclusion of results describes either the result reported or a similar result.
into the tables is that they must have been measured by Table I summarises the best measurements for cells
a recognised test centre listed in an earlier issue.2 A and submodules, Table II shows the best results for
distinction is made between three different eligible modules and Table IV shows the best results forareas: total area; aperture area and designated concentrator cells and concentrator modules. Table III
illumination area.1 ‘Active area’ efﬁciencies are not contains what might be described as ‘notable excepincluded. There are also certain minimum values of the tions’. While not conforming to the requirements to bearea sought for the different device types (above recognised as a class record, the cells and modules in
005 cm2 for a concentrator cell, 1 cm2 for a 1-sun cell, this table have notable characteristics that will be ofand 800 cm2 for a module).1
interest to sections of the photovoltaic community withentries based on their signiﬁcance and timeliness.
To ensure discrimination, Table III is limited to* Correspondence to: Martin A. Green, ARC Photovoltaics Centre of
nominally
10 entries with the present authors having
Excellence, University of New South Wales, Sydney 2052, Australia.
yvoted for their preferences for inclusion. Readers who
E-mail: m.green@unsw.edu.au
Copyright # 2008 John Wiley & Sons, Ltd.

436

M. A. GREEN ET AL.

Table I. Conﬁrmed terrestrial cell and submodule efﬁciencies measured under the global AM15 spectrum(1000 W/m2) at 258CClassiﬁcation

Efﬁc.y (%)

SiliconSi (crystalline)
Si (multicrystalline‘)Si (thin-ﬁlm transfer)
Si (thin-ﬁlm submodule)

247  05
203  05
166  04
104  03

400 (da) 0706
1002 (ap) 0664
4017 (ap) 0645
940 (ap) 0492ô

422
377
328
295ô

828
809
782
721

Sandia (3/99)
NREL (5/04)
FhG-ISE (7/01)
FhG-ISE (8/07)

UNSW PERL10
FhG-ISE11
U. Stuttgart (45 mm thick)12
CSG Solar (1–2 mm on glass;20 cells)13259  08
245  05
182  05
219  07

0998 (ap)1002 (t)4011 (t)402 (t)

1038
1029
0994
0878

294
288
230
293

847
825
797
854

FhG-ISE (12/07)
FhG-ISE (5/05)
NREL (11/95)
NREL (4/90)

Radboud U. Nijmegen5
Radboud U. Nijmegen5
RTI, Ge substrate14
Spire, epitaxial15

192  06#
166  04
165  05#0994(ap) 0716
160 (ap) 0661ô
1032 (ap) 0845

333
334ô
259

803 NREL (1/08)
751 FhG-ISE (3/00)
755 NREL (9/01)

NREL, CIGS on glass6
U. Uppsala, four serial cells16
NREL, mesa on glass1795  03
101  02

1070 (ap)1199 (ap)

0859
0539

175
244

630 NREL (4/03)
766 JQA (12/97)

U. Neuchatel18
Kaneka (2 mm on glass)19

104  03
82  03
82  03

1004(ap) 0729
2545 (ap) 0703ô
1850 (ap) 0659ô

218
190ô
198ô

652 AIST (8/05)
612 AIST (12/07)
629 AIST (6/08)

Sharp20
Sharp, nine serial cells7
Sony, eight serial cells8

515  03
11  03

1021(ap) 0876
2328 (ap) 293

940
0072

625 NREL(12/06)
512 NREL (3/08)

Konarka21
Plextronics (P3HT/PCBM)9320  15303258  13
117  04

3989(t)2622
40 (t) 2488
400 (t)—1423(ap) 5462

1437
1422
—
299

850
856
—
713

Spectrolab (monolithic)
Japan Energy (monolithic)22
Kopin/Boeing (4-terminal)23
Kaneka (thin ﬁlm)24

III–V cells
GaAs (crystalline)
GaAs (thin ﬁlm)
GaAs (multicrystalline)
InP (crystalline)
Thin-ﬁlm chalcogenide
CIGS (cell)
CIGS (submodule)
CdTe (cell)
Amorphous/nanocrystalline Si
Si (amorphous)
Si (nanocrystalline)
Photochemical
Dye sensitisedyy
Dye sensitised (submodule)yy
Dye sensitised (submodule)yy
Organic
Organic polymeryy
Organic (submodule)yy
Multijunction devices
GaInP/GaAs/GeGaInP/GaAs
GaAs/CIS (thin ﬁlm)
a-Si/mc-Si (thin submodule)zz

Areaz
(cm2)

Voc
(V)

Jsc
FFx Test centrejj(mA/cm2) (%) (and date)

NREL (1/03)
JQA (4/96)
NREL (11/89)
AIST (9/04)

Description

CIGS, CuInGaSe2; a-Si, amorphous silicon/hydrogen alloy.
Efﬁc., efﬁciency.
z(ap), aperture area; (t), total area; (da), designated illumination area.
xFF, ﬁll factor.
jj
FhG-ISE, Fraunhofer Institut für Solare Energiesysteme; JQA, Japan Quality Assurance; AIST, Japanese National Institute of Advanced
Industrial Science and Technology.
ôReported on a ‘per cell’ basis.
#
Not measured at an external laboratory.
Stabilised by 800 h, 1 sun AM15 illumination at a cell temperature of 508C.
yy
Stability not investigated.
zz
Stabilised by 174 h, 1 sun illumination after 20 h, 5 sun illumination at a sample temperature of 508C.
yhave suggestions of results for inclusion into this table
are welcome to contact any of the authors with fulldetails. Suggestions conforming to the guidelines will
be included on the voting list for a future issue. (Asmaller number of ‘notable exceptions’ for concentrator cells and modules additionally is included inTable IV, as are results under a relatively new low
aerosol optical depth direct-beam spectrum4).
Copyright # 2008 John Wiley & Sons, Ltd.

Six new results are reported in the present versionsof the tables, only slightly down from the record
number of eight in the previous version.3
The ﬁrst new result appears in Table I. An efﬁciencyof 259% was measured at the Fraunhofer Institute for
Solar Energy Systems (FhG-ISE) for a 1 cm2 GaAs cellfabricated by Radboud University Nijmegen of theNetherlands. This result displaced one of the oldest
Prog. Photovolt: Res. Appl. 2008; 16:435–440
DOI: 10.1002/pip

SOLAR CELL EFFICIENCY TABLES

437

Table II. Conﬁrmed terrestrial module efﬁciencies measured under the global AM15 spectrum (1000 W/m2) at a celltemperature of 258CClassiﬁcation

Si (crystalline)
Si (large crystalline)
Si (multicrystalline)
Si (thin-ﬁlm polycrystalline)
CIGSS
CdTe
a-Si/a-SiGe/a-SiGe (tandem)ô

Efﬁc.y
(%)

Areaz
(cm2)

Voc
(V)

Isc
(A)

FFx
(%)

Test centre(and date)

Description

227  06
201  06
153  04jj
82  02
134  07
107  05
104  05778 (da)16 300 (ap)1017 (ap)661 (ap)
3459 (ap)4874 (ap)905 (ap)

560
661
146
250
312
2621
4353

393
630
136
0318
216
3205
3285

803
787
786
680
689
623
660

Sandia (9/96)
Sandia (8/07)
Sandia (10/94)
Sandia (7/02)
NREL (8/02)
NREL (4/00)
NREL (10/98)

UNSW/Gochermann25
SunPower26
Sandia/HEM27
Paciﬁc Solar (1–2 mm on glass)28
Showa Shell (Cd free)29
BP Solarex30
USSC (a-Si/a-Si/a-Si:Ge)31

CIGSS, CuInGaSSe; a-Si, amorphous silicon/hydrogen alloy; a-SiGe, amorphous silicon/germanium/hydrogen alloy.
Efﬁc., efﬁciency.
z(ap), aperture area; (da), designated illumination area.
xFF, ﬁll factor.
jj
Not measured at an external laboratory.
ôLight soaked at NREL for 1000 h at 508C, nominally 1 sun illumination.
yresults in the previous editions of these tables, a 251%
efﬁcient cell made by the Kopin Corporation in 1990.
Radboud University also have previously fabricatedthe best thin-ﬁlm GaAs cell listed in Table I.5 A paperon this work is in preparation.
The second new result also appears in Table I
where efﬁciency improvement to 192% is reported
for a 1 cm2 thin-ﬁlm polycrystalline CIGS (copper
indium gallium diselenide) cell fabricated andmeasured by the National Renewable Energy Laboratory (NREL)6 improving on the Laboratory’s earlier
188% result.

The third new result again appears in Table I where
82% efﬁciency is reported for a 25 cm2 dye sensitisedcell submodule fabricated by Sharp7 and measured by
the Japanese National Institute of Advanced Industrial
Science and Technology (AIST). This improves thecompany’s previous benchmark of 79% efﬁciency forsuch a submodule.
The fourth new result is also reported for the same
category in Table I where an 82% efﬁciency is also
reported for a similarly sized dye sensitised cell
submodule (185 cm2) fabricated by Sony8 andmeasured by AIST.

Table III. ‘Notable exceptions’: ‘top 10’ conﬁrmed cell and module results, not class records (global AM15 spectrum,
1000 W/m2, 258C)Classiﬁcation

Cells (silicon)
Si (MCZ crystalline)
Si (moderate area)
Si (large FZ crystalline)
Si (large CZ crystalline)
Si (large multicrystalline)
Cells (other)
GaInP/GaInAs/GaInAs(tandem)
CIGS (thin ﬁlm)
a-Si/a-Si/a-SiGe (tandem)
Photoelectrochemicalx
Organic

Efﬁc.y
(%)

Areaz
(cm2)

Voc
(V)

245  05
237  05
218  07
223  06
181  05

40 (da)221 (da)1474 (t)1005 (t)1377 (t)

0704
0704
0677
0725
0636

416
415
400
391
369

835
810
806
791
770

338  15jj

025 (ap) 2960

131868 NREL (1/07)

NREL, monolithic36199  06jj 0419 (ap) 0692
121  07
027 (da) 2297
111  03 0219 (ap) 0736
54  03x 0096 (ap) 0856

355
756
209
970

810
697
722
653

NREL, CIGS on glass37
USSC stabilised (monolithic)38
Sharp, dye sensitised39
Plextronics9

Jsc
FF Test centre(mA/cm2) (%) (and date)

Sandia (7/99)
Sandia (8/96)
FhG-ISE (3/06)
AIST (7/07)
FhG-ISE (8/05)

NREL (10/07)
NREL (10/96)
AIST (3/06)
NREL (7/07)

Description

UNSW PERL, SEH MCZ substrate32
UNSW PERL, FZ substrate25
SunPower FZ substrate33
Sanyo HIT, n-type CZ substrate34
U. Konstanz, laser grooved35

CIGS, CuInGaSe2.
Efﬁc., efﬁciency.
z(ap), aperture area; (t), total area; (da), designated illumination area.
x
Stability not investigated.
jj
Not measured at an external laboratory.
y

Copyright # 2008 John Wiley & Sons, Ltd.

Prog. Photovolt: Res. Appl. 2008; 16:435–440
DOI: 10.1002/pip

438

M. A. GREEN ET AL.

Table IV. Terrestrial concentrator cell and module efﬁciencies measured under the direct-beam AM15 spectrum at a celltemperature of 258CClassiﬁcation

Single Cells
GaAs
Si
CIGS (thin ﬁlm)
Multijunction cells
GaInP/GaAs/Ge (2-terminal)
Submodules
GaInP/GaAs/Ge
ModulesSi
Low-AOD spectrum
GaInP/GaInAs/Ge (2-terminal)
GaInP/GaAs/GaInAs
Si‘Notable exceptions’
GaAs/GaSb (4-terminal)
InP/GaInAs (3-terminal)
GaInP/GaInAs (2-terminal)
GaAs (high concentration)
Si (large area)

Efﬁc.
(%)

Areay
(cm2)

Intensityz(suns)

278  10
273  10
215  15jj

0203 (da)100 (da)0102 (da)347  17

Test centre(and date)

Description

216
93
14

Sandiax (8/88)
FhG-ISE (9/07)
NREL (2/01)

Varian, Entech cover40
Amonix back-contact41
NREL

0267(da)333

NREL (9/03)

Spectrolab, monolithic

270  15

34 (ap)10

NREL (5/00)

ENTECH42203  08jj

1875 (ap)80

Sandia (4/89)

Sandia/UNSW/ENTECH (12 cells)43407  24ô 0267 (da)40.1  2.4 0.0976 (da)276  10ô
100 (da)

240
143
92

NREL (9/06)
NREL (4/08)
FhG-ISE (11/04)

Spectrolab, lattice-mismatched44
NREL, inverted monolithic
Amonix back-contact45

326  17
0053 (da)318  16jj 0063 (da)302  12 01330 (da)262  100203 (da)216  :07
200 (da)

100
50
300
1000
11

Sandiax (10/89)
NREL (8/90)
NREL/FhG-ISE (6/01)
Sandiax (8/88)
Sandiax (9/90)

Boeing, mechanical stack46
NREL, monolithic47
Fraunhofer, monolithic48
Varian49
UNSW laser grooved50



Efﬁc., efﬁciency.
(da), designated illumination area; (ap), aperture area.
z
One sun corresponds to direct irradiance of 1000 W/m2.
x
Measurements corrected from originally measured values due to Sandia recalibration in January 1991.
jj
Not measured at an external laboratory.
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Prog. Photovolt: Res. Appl. 2008; 16:435–440
DOI: 10.1002/pip