PROGRESS IN PHOTOVOLTAICS RESEARCH AND APPLICATIONS, VOL 3, 229-233 (1995)
Research
Shout Communication:
Solar Cell Eficiency Tables (Version 6) Martin A. Green’, Keith Emery’, Klaus Bucher3 and David L. King4
’
Centre for Photovoltaic Devices and Systems, University of New South Wales, Sydney 2052, Australia; ’National Renewable Energy Laboratory, 161 7 Cole Boulevard, Golden, C O 80401, U S A ; Fraunhofer-lnstitut fur Solare Eneryiesysteme, Oltmannsstrasse 5, 0-79100 Freiburg, Germany; Sandia National Laboratories, Department 6219, 1515 Eubank Street, Albuquerque, N M 87123, U S A
’
Updated tables showing an extensive listing of the highest independently confirmed eflciencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and several new entries since January 1995 are briefly described.
INTRODUCTION ince January 1993 Progress in Photovoltaics has published six-monthly listings of the highest confirmed efficiencies for a range of photovoltaic cell and module technologies.‘ 3 By establishing ’ guidelines for the inclusion of results into these tables, this not only provides an authoritative summary of the current state of the art but also encourages researchers to seek independent confirmation of results and to report results on a standardized basis. Briefly, the main criterion for inclusion of results in these tables is that they be measured at one of the designated test centres listed in the Appendix, under standardized test conditions. A distinction is also made between three different cell area measurements: total area, aperture area and designated ‘Active area’ efficiency measurements are not included. There are also certain illumination minimum values of area encouraged for the different cell types, although some discretion is exercised here (0.05 cm2 for a concentrator cell, 0.25 cmz for a tandem cell, 1 cm2 for a one-sun cell and 800 cm2 for a module).
NEW RESUL TS Highest confirmed cell results are reported in Tables 1-111. Changes in the tables from those previously published’ are set in bold type. Table I summarizes the best measurements for cells and submodules, Table I1 shows the best results for modules and Table I11 shows the best results for concentrator cells and concentrator modules. New results since January 1995 relate to polycrystalline thin-film cells based on copper-indium-gallium diselenide (CIGS). On-going improvements with this technology have seen an efficiency of 17.1% for a cell fabricated at the National Renewable Energy Laboratory (NREL), confirmed in April 1995. Unfortunately, the area of this cell is too small for inclusion in these tables. However, the same group at NREL have fabricated a 16.4% efficient cell of greater than 1 cmz area. This result is shown in Table I in bold type, as are other changes to Tables 1-111. These other changes correct minor errors in the previously published version of the table^.^
ccc 1062-1995/95/040229-5
0 1995 by John Wiley & Sons, Ltd
Received 8 May 1995 Revised 15 May 1995
230
M. A . GREEN ET AL.
Table I. Confirmed terrestrial cell and submodule efficiencies measured under the global AM1.5 spectrum (loo0W m-’) at 25°C Classification’
E f f i ~ . ~Area’ (cm’)
(%)
v,,
4,
(V)
(mA/cm’)
FFd Test centree (%) (and date)
Description
Silicon cells
Si (crystalline) Si (moderate area) Si (multicrystalline) Si (large multicystalline) Si (thin crystalline) Si (supported film) Si (large thin film)
24.0 21.6 17.8 17.2 17.0 14.9 14.2
Ill-v GaAs (crystalline cell) GaAs (Ge substrate cell) GaAs (thin film cell) GaAs (submodule) InP (crystalline cell)
25.1 24.3 23.3 21.0 21.9
Polycrystalline thin film CdTe (cell) CdTe (submodule) CIGS (cell) CIGSES (submodule)
15.8 9.8 16.4 12.7
40.9 39.4 36.2 36.4 32.6 0.600 31.4 0.608 30.0
82.7 78.1 78.5 77.7 80.3 79.2 78.1
JQA (3/93) Sandia (9/94) Sandia‘ (12/88) JQA (3/93)
3.91 (t) 4.00 (t) 4.00 (ap) 16 (t) 4.02 (t)
1.022 1.035 1.011 4.04 0.878
28.2 27.6 27.6 6.6 29.3
87.1 85.3 83.8 80 85.4
NREL NREL NREL NREL NREL
1.05 (ap) 63.6 (ap) 1.025 (t) 69.1 (ap)
0.843 6.62 0.678 7.49
25.1 2.2 32.0 2.49
74.5 69 68.0
NREL (6/92) NREL (5/93) NREL (11/94) NREL (4/94)
South Florida CSVT Solar Cells Inc. NREL, CIGS on glass Siemens (prism cover)
0.887 12.5
19.4 1.3
74.1 73.5
JQA (4/92) JQA (12/92)
Sanyo Sanyo
2.385 2.403 1.621 2.541 2.289
14.0 14.0 11.7 7.0 7.9
88.5 83.4 -
NREL NREL NREL NREL NREL NREL
NREL (monolithic) Varian (monolithic) Kopin/Boeing (4-terminal) ARC0 (4-terminal) USSC/Cannon (monolithic) ECD (monolithic) Sharp (monolithic)
4.00 (ap) 45.7 (t) 1.0 (ap) 100 0) 4.02 (ap) 1.02 (ap)
100 0)
0.709 0.694 0.628 0.610 0.651
75.8
Sandia (9/94) Sandia (4/93) Sandia (3/94)
(3/90) (3/89) (4/90) (4/90) (4/90)
UNSW PERL UNSW PERL Georgia Tech Sharp (mech. textured) ANU (20 pm thick) AstroPower (Si-film) Mitsubishi (60 pm on SiO,)
Kopin, AlGaAs window ASEC, AlGaAs window Kopin, 5-pm CLEFT Kopin (4 CLEFT cells) Spire, epitaxial
Amorphous Si
a-Si (celly a-Si (submoduley
12.7 12.0
Multijunction cells GaInP/GaAs GaAIAs/GaAs GaAs/CIS (thin film) a-Si/CIGS (thin filmy a-Si/a-SiGd a-Si/a-Si/a-SiGd a-Si/a-SiGe/a-SiGe‘
29.5 27.6 25.8 14.6 12.5 12.4 12.4
1.0 (da) 100 (ap)
0.25 (t) 0.50 (t) 4.00 (t) 2.40 (ap) 0.26 (ap) 0.27 (t) 1.0 (da)
-
65.8 70.0 68.5
(6/93) (3/89) (11/89) (6/88) (12/92) (2/88) JQA (12/92)
’CIGS = CuInGaSe,; CIGSES = CuInGaSeS; a-Si = amorphous silicon/hydrogen alloy. Effic. = efficiency. (ap) = aperture area; (t) = total area; (da) = designated illumination area. FF = fill factor. ‘JQA = Japan Quality Assurance. Measurements corrected from originally measured values due to Sandia recalibration in January 1991. Unstabilized results.
‘
To accommodate results such as the 17.1% cell efficiency mentioned above, a fourth table will, in this and future updates, complement Tables 1-111. This table (Table IV) contains what might be described as ‘notable exceptions’. While not conforming to the requirements to be recognized as a class record, the cells and modules in this table will have notable characteristics that will be of interest to sections of the photovoltaic community. The results reported in this table may be removed once their timeliness wanes, with an arbitrary cap of 10 entries imposed to encourage turnover.
SOLAR CELL EFFICIENCY TABLES
231
Table 11. Confirmed terrestrial module efficiencies measured under the global AM1.5 spectrum (lo00 W m-') at a cell temperature of 25°C E f f i ~ . ~Area' (cm')
Classification"
(%)
&,
&c
FFd Test centre'
(V)
(A)
(%)
(and date)
Description
81.3 78.6 64 64 55 60 61.2
Sandia (2/94) Sandia (10/94) NREL (6/88) NREL (5/91) NREL (9/91) NREL (10/93) NREL (12/93)
Honda/SunPower, 48 cells Sandia/HEM ARCO, 55 cells Siemens Solar Photon Energy Solar Cells, Inc. USSC
~
21.6 15.3 11.1 9.7 8.1 7.8 10.2
Si (crystalline) Si (multicrystalline) CIGS CIGS (large) CdTe' CdTe (large) a-Si/a-SiGe/a-SiCe (tandem)'
~~
862 (ap) 1017 (ap) 938 (ap) 3883 (ap) 838 (ap) 6838 (ap) 903 (ap)
32.6 14.6 25.9 37.8 21.0 92.0 2.32
0.703 1.36 0.637 2.44 0.573 0.969 6.47
' CIGS = CuInGaSe,; a-Si = amorphous silicon/hydrogen alloy; a-SiGe = amorphous silicon/germanium/hydrogen alloy. Effic. = efficiency.
' (ap) = aperture area. FF = fill factor. Output vanes with premeasurement conditions and bias rate. Efficiency taken with maximum power point tracking. Stabilized results.
Table 111. Terrestrial concentrator cell and module efficiencies measured under the direct beam AM1.5 spectrum at a cell temperature of 25°C Effic." Classification
(%)
Single cells GaAs Si Si (moderate area) Si (large) GaAs (Si substrate)
27.6 26.5 25.7 21.6 21.3
Multijunction cells GaAs/GaSb InP/GaInAs GaAs/GaInAsP GaInP/GaAs GaAs/Si
32.6 31.8 30.2 30.2 29.6
Submodules GaAs/GaSb
25.1
Modules Si
20.3
*
Areab (cm')
Concentration' (suns)
Test centre (and date)
Description
0.126 (da) 0.150 (da) 1.21 (da) 20.0 (da) 0.126 (da)
255 140 74 11 237
Sandia (5/91) Sandiad(5/87) Sandia (7/93) Sandiad(9/90) Sandia (5/91)
Spire Stanford point contact SunPower rear contact UNSW laser-grooved Spire
0.053 (da) 0.063 (da) 0.053 (da) 0.103 (da) 0.317 (da)
100 50 40 180 3 50
Sandiad(10/89) NREL (8/90) NREL (lo/%) Sandia (3/94) Sandiad(9/88)
Boeing, mechanical stack NREL, monolithic 3-terminal NREL, stacked Cterminal NREL, monolithic 2-terminal Varian/Stanford/Sandia, mech. stack
57
Sandia (3/93)
Boeing, 3 mech. stack units
80
Sandia (4/89)
Sandia/UNSW/ENTECH (12 cells)
41.4 (ap) 1875 (ap)
* Effic. = efficiency. b(da) = designated illumination area; (ap) = aperture area. 'One sun corresponds to an intensity of lo00 W m-*. Measurements corrected from originally measured values due to Sandia recalibration in January 1991.
To initiate Table IV the 17.1%CIGS cell result mentioned above is included, although it is ineligible for inclusion in the main table owing to the small cell area. Also included are results mentioned previ~usly,~ specifically the 17.3% efficiency confirmed by the Fraunhofer Institute, Freiburg (FhG-ISE) for a cell fabricated on a 48-pm thick silicon layer grown expitaxially on a low-resistivity silicon substrate by the Max Planck Institute, Stuttgart (MPI). The total device thickness of this cell is much thicker than 48 pm so it is ineligible for inclusion in the main tables, because it would not be competitive with cells of the same total silicon thickness.
232
M . A . GREEN ET A L .
Table IV. 'Notable exceptions': confirmed cell and module results, not class records (Global AM1.5 spectrum, loo0 W m-' at 25°C)
Effi~.~Areac
Kc
J*c
FF
Classification"
(%)
(cm2)
(V)
(mA/cm*)
(%)
Test centre (and date)
Single cells Si (crystalline cell)
173
4.qap)
0.655
32.5
81.1
FhGISE(4/94)
ClCS (thin-film cell)
17.1
0.413(t)
0.654
33.9
77.1
NREL (4/95)
MPI, 48 pm epi/thick substrate NREL, CIGS on glass
Module Si (spheralTMmodule)
10.3
3931(ap)
20.1
0.692
73.6
NREL (9/94)
Texas Instruments
Description
CIGS = CulnGaSe,. Effic. = efficiency. ' (ap) = aperture area; (1) = total area.
a
The third entry is for the large spheralTMcell module previously included in Table 11. The reason for transferring this result is that it involves a unique manufacturing approach and hence may never have any direct competition if kept in a separate category. The result is not, however, competitive with the multicrystalline cell module result that is retained in Table 11. Finally, an updated list of designated test centres follows, with changes from the previous printing5 marked in bold type. Disclaimer While the information in the tables is provided in good faith, the authors, editors and publishers cannot accept direct responsibility for any errors or omissions. Acknowledgements One of the authors (M.A.G.) would like to thank J. Nose and S. Igari of the Japan Quality Assurance Organization for assistance in preparing these tables.
APPENDIX
List of designed test centres European Solar Test Installation (ESTI), CEC Joint Research Centre, 21020 Ispra (Varese), Italy. Contact: Dr Heinz Ossenbrink. Tel.: (39) 332-789-196; Fax.: (39) 332-789-268. (Terrestrial cells and modules) Fraunhofer-Institut fur Solare Energiesysteme (Fraunhofer-ISE), Oltmannsstrasse 5 , D-79 100 Freiburg, Germany. Contact: Dr Klaus Bucher/Siegfried Kunzelmann. Tel.: (49) 761-4588-145/146; Fax.: (49) 76 1-4588-100. (Terrestrial and space cells and modules) Japan Quality Assurance Organization (JQA), Solar Techno Center, Solar Cell Test Research Division, HIC Bldg 2F, 4588 Murakushi-cho, Hanamatsu-shi, Shizuoka-ken, 431-12,Japan. Contact: Junta Nose/ Sankazu Igari. Tel.: (81) 53-484-4101; Fax.: (81) 53-484-4102. (Terrestrial cells and modules) NASA Lewis Research Center, MS 302-1,210oO Brookpark Road, Cleveland, OH 44135, USA. Contact: Dr David Brinker, Senior Research Engineer. Tel.: (1) 216-433-2236; Fax.: (1) 216-433-6106. (AM0 cell measurements)
SOLAR CELL EFFICIENCY TABLES
233
National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, CO 80401, USA. Contact: Mr Keith Emery, Tel.: ( 1) 303-384-6632; Fax.: (1) 303-384-6490. (Terrestrial and concentrator cells and modules) Physikalisch-Technische Bundesanstalt., Bundesallee 100, D-38 116 Braunschweig, Germany. Contact: Dr Jiirgen Metzdorf/Thomas Wittchen. Tel.: (49) 531-592-4100/-4181; Fax.: (49) 531-592-9292. (Terrestrial and AM0 cells) Royal Aircraft Establishment, Defence Research Agency, Farnborough, Hampshire GU 14 6TD, UK. Contact: C. Goodbody, Space Technology Dept, P234 Building. Tel.: (44) 252-24461; Fax.: (44) 252-377121. (Primarily AM0 calibrations) Sandia National Laboratories, 1515 Eubank SE, Albuquerque, NM 87123, USA. Contact: Mr David King, Dept. 6219, MS-0752.Tel.: (1) 505-844-8220; Fax.: (1) 505-844-6541; Email:
[email protected]. (Terrestrial and concentrator cells and modules)
REFERENCES 1. M.A. Green and K. Emery, ‘Solar cell efficiency tables’, Progr. Photovolt., 1, 25-29 (1993). 2. M.A. Green and K. Emery, ‘Solar cell efficiency tables (version 2)’, Progr. Photovolt., 1, 225-228 (1993). 3. M.A. Green and K. Emery, ‘Solar cell efficiency tables (version 3)’, Progr. Photovolt., 2, 27-34 (1994). 4. M.A. Green and K. Emery, ‘Solar cell efficiency tables (version 4)’, Progr. Photooolt., 2, 231-234 (1994). 5. M.A. Green, K. Emery, K. Biicher and D. L. King, ‘Solar cell efficiency tables (version S)’, Progr. Photovolt., 3, 51-55 (1995).
