Since January 1993, ‘Progress in Photovoltaics’ has published six monthly listings of the highest confirmed 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 allows 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 standardised basis. In version 33 of these tables , results were updated to the new internationally accepted reference spectrum (IEC 60904-3, Ed. 2, 2008), where this was possible.
The most important criterion for inclusion of results into the tables is that they must have been independently measured by a recognised test centre listed elsewhere . A distinction is made between three different eligible definitions of cell area: total area, aperture area and designated illumination area, as also defined elsewhere . ‘Active area’ efficiencies are not included. There are also certain minimum values of the area sought for the different device types (above 0.05 cm2 for a concentrator cell, 1 cm2 for a one-sun cell and 800 cm2 for a module).
Results are reported for cells and modules made from different semiconductors and for subcategories within each semiconductor grouping (e.g. crystalline, polycrystalline and thin film). From version 36 onwards, spectral response information is included when available in the form of a plot of the external quantum efficiency (EQE) versus wavelength, either as absolute values or normalised to the peak measured value. Current–voltage (I–V) curves have also been included where possible from version 38 onwards.
2 NEW RESULTS
Highest confirmed ‘one-sun’ cell and module results are reported in Tables 1 and 2. Any changes in the tables from those previously published  are set in bold type. In most cases, a literature reference is provided that describes either the result reported or a similar result (readers identifying improved references are welcome to submit to the lead author). Table 1 summarises the best measurements for cells and submodules, whereas Table 2 shows the best results for modules. Table 3 contains what might be described as ‘notable exceptions’. Although not conforming to the requirements to be recognised as a class record, the cells and modules in this table have notable characteristics that will be of interest to sections of the photovoltaic community, with entries based on their significance and timeliness.
Table 1. Confirmed terrestrial cell and submodule efficiencies measured under the global AM1.5 spectrum (1000 W/m2) at 25 °C (IEC 60904-3: 2008, ASTM G-173-03 global).
NREL, National Renewable Energy Laboratory; FhG-ISE, Fraunhofer Institut für Solare Energiesysteme; AIST, Japanese National Institute of Advanced Industrial Science and Technology; UNSW, University of New South Wales.
AIST, Japanese National Institute of Advanced Industrial Science and Technology; NREL, National Renewable Energy Laboratory; FhG-ISE, Fraunhofer Institut für Solare Energiesysteme; ESTI, European Solar Test Installation.
To encourage discrimination, Table 3 is limited to nominally 10 entries with the present authors having voted for their preferences for inclusion. Readers who have suggestions of results for inclusion into this table are welcome to contact any of the authors with full details. Suggestions conforming to the guidelines will be included on the voting list for a future issue.
Table 4 shows the best results for concentrator cells and concentrator modules (a smaller number of ‘notable exceptions’ for concentrator cells and modules additionally are included in Table 4).
Table 4. Terrestrial concentrator cell and module efficiencies measured under the ASTM G-173-03 direct beam AM1.5 spectrum at a cell temperature of 25 °C.
Thirteen new results are reported in the present version of these tables. The first new result in Table 1 is a very recent result, the demonstration of 19.6% efficiency for a 1-cm2 CdTe cell fabricated by GE Global Research  and measured by the Newport Technology and Application Center. This is a significant improvement upon the previous best efficiency of 18.3% for a CdTe cell of this size and equals the outright record for any polycrystalline thin-film cell. This remains the most efficient CdTe cell above the minimum area (1 cm2) deemed reasonable for inter-technology comparisons.
The second new cell result in Table 1 is an improvement in the performance of a 1-cm2 nanocrystalline (sometimes called microcrystalline) silicon solar cell to 10.7%, significantly improving upon one of the oldest results in these tables. The cell was fabricated by École Polytechnique Fédérale de Lausanne (EPFL)  and measured at the Fraunhofer Institute for Solar Energy Systems (FhG-ISE).
A third new result in Table 1 is an improvement in efficiency to 8.2% for a 25-cm2 organic cell submodule fabricated by Toshiba  and measured by the Japanese National Institute of Advanced Industrial Science and Technology (AIST). Along with other emerging technology devices, the stability of this device was not investigated, although the stability of earlier devices is reviewed elsewhere . This improves upon the 6.8% result for a much larger submodule (396 cm2) also reported by Toshiba in the previous issue of these tables .
A fourth major new result in Table 1 is a new record for energy conversion efficiency for any photovoltaic converter that does not use sunlight concentration. An efficiency of 37.9% is reported for a 1-cm2 InGaP/GaAs/InGaAs monolithic multijunction cell fabricated by Sharp  and again measured at AIST.
The first new result in Table 2 is a new record for a large area silicon module. An efficiency of 22.4% is reported for a 1.6-m2 silicon module fabricated by SunPower  and measured by NREL. A SunPower representative described this as a standard commercial module that “would be on someone's roof” if it had not been sent to NREL for calibration.
The second new result reported in Table 2 is a record for any polycrystalline thin-film module, with 16.1% total area efficiency reported for a 0.72-m2 CdTe module fabricated by First Solar  and again measured at NREL. Notable features of this result are that the efficiency is reported on a total area basis (includes the largely inactive isolation area around the edge of the module) and that the module is monolithic (some thin-film approaches allow pre-selection of the cells included in the module, which somewhat reduces the challenge in producing high-efficiency modules).
Several new ‘notable exceptions’ are reported in Table 3. The first is a new efficiency record for a large-area silicon cell with 24.7% efficiency reported for a 102-cm2 HIT cell (Heterojunction with Intrinsic Thin-layer cell) fabricated on an n-type silicon wafer substrate by Panasonic  and measured by AIST.
The second new result in Table 3 is 20.8% efficiency for a small area (0.25 cm2) crystalline GaInP cell fabricated and measured by NREL. The notable feature of this cell is the high efficiency for such a high-bandgap material (1.80 eV), evidence for a high radiative efficiency .
The third new result is 20.4% efficiency for a small area (0.52 cm2) flexible CuInxGa1 − xSe2 (CIGS) cell developed by EMPA, the Swiss Federal Laboratory for Materials Science and Technology, and measured at FhG-ISE. This is the highest confirmed efficiency for any CIGS cell, although the cell area is too small for consideration as an outright record.
A fourth new result in Table 3 is 19.7% efficiency for a small area (0.5 cm2) CuInxGa1 − xSySe2 − y cell fabricated by Showa Shell Sekiyu K.K. and the Tokyo University of Science  and measured by AIST. The notable feature of this result is that the cell is Cd-free, allowing it to comply with legislation such as the European Restriction on Hazardous Substances .
The fifth new result in Table 3 relates to an efficiency increase to 8.5% for a small area (0.24 cm2) pure sulphide CZTS (copper tin zinc sulphide) solar cell fabricated by Toyota Central R&D Laboratories  and measured at AIST. This cell is also much smaller than the 1-cm2 size required for consideration as an outright record.
The final new result in Table 3 introduces a new cell type into these Tables, the perovskite cell which has evolved from research into dye-sensitised cells. Recent good results have been reported using the perovskite methylammonium triiodideplumbate (CH3NH3PbI3) as the absorber and transport layer . An efficiency of 14.1% has subsequently been confirmed for a small area cell (0.2-cm2) fabricated by EPFL and measured at the Newport Technology and Application Center, again too small to be classified as an outright record. The rapid rate of increase in performance over recent months for this device suggests that the full efficiency potential remains untapped. The high Pb content of the above-mentioned perovskite (33%) means that devices based on this material would not comply with legislation such as the European ROHS  without an exemption or exclusion, such as presently does exist for photovoltaic systems.
Table 4 reports one new result for concentrator cells. A new record of 44.4% for the conversion of sunlight by any means is reported for a 0.165-cm2 multijunction cell operating at a concentration of 302 suns (direct irradiance of 302 kW/m2). The cell is an InGaP/GaAs/InGaAs triple junction device fabricated by Sharp  and measured at FhG-ISE.
The EQE for the new CZTS, GaInP and perovskite cell, the new CdTe module as well as for the organic submodule results are shown in Figure 1(a). Figure 1(b) shows the EQE for the new silicon cell and module results reported in the present issue of these tables. Figure 1(c) shows the EQE for two of the new III–V multijunction cell results.
Figure 2 shows the current density–voltage (J–V) curves for the corresponding devices. For the case of modules, the measured current–voltage data has been reported on a ‘per cell’ basis (measured voltage has been divided by the known or estimated number of cells in series, whereas measured current has been multiplied by this quantity and divided by the module area). For the concentrator cell, the current density has been normalised by the sunlight concentration ratio.
Although the information provided in the tables is provided in good faith, the authors, editors and publishers cannot accept direct responsibility for any errors or omissions.
The Australian Centre for Advanced Photovoltaics commenced operation in 2013 with support from the Australian Renewable Energy Agency.