Article
Energy & Fuels
Ian Marius Peters, Carlos David Rodriguez Gallegos, Larry Lueer, Jens A. Hauch, Christoph J. Brabec
Summary: Multijunction solar cells have theoretical conversion efficiencies exceeding 60%, but technical and economic constraints limit the maximum number of junctions and corresponding efficiencies. Spectral variations and optical losses restrict the number of junctions and reduce achievable efficiencies. Sequential cell illumination architecture is more resilient to these losses. Economic considerations suggest that five junctions or less are economically ideal for most applications.
PROGRESS IN PHOTOVOLTAICS
(2023)
Article
Energy & Fuels
Janne Puustinen, Joonas Hilska, Arto Aho, Esperanza Luna, Antti Fihlman, Mircea Guina
Summary: The development of low bandgap GaAsNBi solar cells grown using MBE is reported, and the As/Ga flux ratio is found to play an important role in controlling the solar cell performance.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2024)
Article
Energy & Fuels
Minasadat Heydarian, Christoph Messmer, Alexander J. Bett, Maryamsadat Heydarian, David Chojniak, Öezde S. Kabakli, Leonard Tutsch, Martin Bivour, Gerald Siefer, Martin C. Schubert, Jan Christoph Goldschmidt, Martin Hermle, Stefan W. Glunz, Patricia S. C. Schulze
Summary: Research has found that current matching can be increased for perovskite silicon tandem solar cells by adding a perovskite silicon heterojunction bottom solar cell on top of a planar front/rear side-textured silicon heterojunction bottom solar cell. Optical simulation and planning were used to determine measures for improving the device and maximizing the tandem current density. Variations in the perovskite bandgap and thickness were investigated to achieve current matching between the two subcells. Analysis was also done on limitations such as nonradiative recombination at the perovskite's interfaces. Replacing the hole transport layer PTAA with 2PACz resulted in an increase in the overall certified power conversion efficiency.
Article
Chemistry, Physical
Ryan M. France, John F. Geisz, Tao Song, Waldo Olavarria, Michelle Young, Alan Kibbler, Myles A. Steiner
Summary: The design of multijunction solar cells takes into account both the theoretical optimal bandgap combination and the realistic limitations of materials. By modifying the bandgap of the middle cell using thick GaInAs/GaAsP strain-balanced quantum well solar cells, a high-efficiency triple-junction inverted metamorphic multijunction device has been achieved.
Article
Thermodynamics
Zhixiong Ding, Yunren Sui, Chong Zhai, Zengguang Sui, Haosheng Lin, Fuxiang Li, Wei Wu
Summary: Efficient use of renewable energy, such as solar energy, is crucial for achieving net-zero energy buildings and carbon neutrality. However, the instability and intermittency of renewable energy make it challenging to fully utilize. This study explores the use of a solar absorption thermal battery (SATB) for space cooling in buildings. Through simulations and parametric studies, the SATB is found to achieve satisfactory cooling in different climates, with the highest cooling met ratio of 0.95 in Singapore. The SATB system also demonstrates high energy storage efficiency and density, making it a promising technology for promoting renewable energy utilization in buildings.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Energy & Fuels
Sai Meghasena Chavali, John Roller, Mario Dagenais, Behrang H. Hamadani
Summary: This study measured the external luminescence quantum yields of subcells within multijunction solar cells and utilized the measurements to optimize the electrical models of the cells. The findings showed that electroluminescence measurements can aid in parameter selection and suggested strategies for improving solar cell performance.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Nanoscience & Nanotechnology
Hidenori Mizuno, Kikuo Makita, Hitoshi Sai, Toshimitsu Mochizuki, Takuya Matsui, Hidetaka Takato, Ralph Muller, David Lackner, Frank Dimroth, Takeyoshi Sugaya
Summary: This paper describes a method for fabricating two-terminal tandem solar cells using Si heterojunction bottom cells and GaAs-relevant III-V top cells by smart stack. By introducing hydrogenated nanocrystalline Si layers, the electrical contacts and passivation quality of the cells were improved, resulting in a certified efficiency of 27.4%.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Qiming Zhang, Baoguo Zhang, Hongliang Guo, Yue Tang, Jian Song, Qiang Sun
Summary: This study investigates the performance of low-intensity low-temperature (LILT) GaInP/GaInAs/Ge triple junction (TJ) solar cells grown by metal-organic vapor phase epitaxy (MOVPE). It is found that metamorphic (MM) epitaxy achieved by compositionally graded buffer (CGB) layer helps to reduce strain and improve the performance of solar cells.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Energy & Fuels
Daniel L. Lepkowski, Tyler J. Grassman, Jacob T. Boyer, Daniel J. Chmielewski, Chuqi Yi, Mattias K. Juhl, Anastasia H. Soeriyadi, Ned Western, Hamid Mehrvarz, Udo Romer, Anita Ho-Baillie, Christopher Kerestes, Daniel Derkacs, Steven G. Whipple, Alex P. Stavrides, Stephen P. Bremner, Steven A. Ringel
Summary: The study fabricated a GaAsP/Si tandem solar cell with a certified efficiency of 23.4% using MOCVD growth on an ex-situ produced Si sub cell. The key improvement in efficiency was attributed to advancements in top cell design to maximize short wavelength response, along with identification of key loss mechanisms through in-depth analysis of the tandem cell. Further efficiency gains are expected through addressing issues such as voltage dependent collection efficiency and reducing dislocation density in the top cell and implementing rear surface texture and dielectric passivation in the Si subcell.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2021)
Article
Energy & Fuels
Marc Steiner, Paresh Mathur, Subrata Sarkar, Gerald Siefer
Summary: Energy yield calculations for CPV modules using tandem solar cell technology were conducted and analysed in this study. The PVsyst model showed good agreement with measured data in Freiburg, but had a 10% deviation in Greater Noida due to the high aerosol content impacting spectral irradiance. The PVsyst calculations were improved using SMR corrected DNI values, reducing the deviation between calculated and measured energy yield to below 1%.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Henning Schulte-Huxel, Robert Witteck, Susanne Blankemeyer, Marc Koentges
Summary: Three-terminal (3T) tandem solar cells require an adapted module integration scheme to explore their full efficiency potential. The connection scheme affects the operation of the subcells and resulting current path. Reverse connection can reduce interconnect losses.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Norman Jost, Steve Askins, Richard Dixon, Mathieu Ackermann, Cesar Dominguez, Ignacio Anton
Summary: Micro-concentrator photovoltaics technology reduces the size of components, achieving high efficiencies and cost reductions. The interconnection of multiple solar cells is achieved through direct printing onto front contact pads. This technology has the potential for large-scale implementation.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Environmental Sciences
Alain Robichaud, Paul Comtois
Summary: The study simulated allergenic tree pollen distribution using a regional air quality model, showing superior results compared to other methods and identifying the majority of Betula pollen originating from the Laurentides region. Additionally, birch pollen episodes in Montreal were found to occur only within a specific average daily temperature range.
ENVIRONMENTAL RESEARCH
(2021)
Article
Instruments & Instrumentation
Bingwen Wang, Hongyuan Wang, Xiaonan Mao, Xiang Liu, Zhiqiang Yan, Shaochong Wu
Summary: The study establishes an analytical model of zenith radiance for JHKs bands, using atmospheric absorption and scattering functions to construct the model parameters, and employing the Levenberg-Marquardt (L-M) method and Adaptive Moment Estimation (Adam) method for parameter solving and optimization. The accuracy of the constructed analytical model is evaluated by calculating the mean relative error between the model value and reference data.
INFRARED PHYSICS & TECHNOLOGY
(2021)
Article
Chemistry, Physical
Lukas Hrachowina, Yang Chen, Enrique Barrigon, Reine Wallenberg, Magnus T. Borgstrom
Summary: III-V semiconductor-based planar multi-junction solar cells are today's world-record efficiency solar cells. However, the development of multi-junction NW photovoltaics has been hindered by the inability to electrically connect different materials in an axial geometry. This study demonstrates the design and proof-of-principle of axially defined GaInP/InP/InAsP triple-junction photovoltaic NWs, showing improved light absorption and an open-circuit voltage twice as large as previously reported for tandem-junction photovoltaic NWs.
MATERIALS TODAY ENERGY
(2022)
Article
Chemistry, Physical
Micha Ben-Naim, Reuben J. Britto, Chase W. Aldridge, Rachel Mow, Myles A. Steiner, Adam C. Nielander, Laurie A. King, Daniel J. Friedman, Todd G. Deutsch, James L. Young, Thomas F. Jaramillo
ACS ENERGY LETTERS
(2020)
Article
Physics, Applied
Kevin L. Schulte, Ryan M. France, Daniel J. Friedman, Alina D. LaPotin, Asegun Henry, Myles A. Steiner
JOURNAL OF APPLIED PHYSICS
(2020)
Article
Chemistry, Physical
Tao Song, Daniel J. Friedman, Nikos Kopidakis
Summary: Emerging photovoltaic technologies have gained remarkable attention for their rapid efficiency growth and transition toward commercialization. Accurate efficiency measurements are crucial for these technologies, but are more complicated due to their dynamic responses and susceptibility to degradation. Comprehensive efficiency calibration and reporting steady-state efficiency are important for better comparisons between reported efficiencies.
ADVANCED ENERGY MATERIALS
(2021)
Article
Energy & Fuels
William E. McMahon, Henning Schulte-Huxel, Jeronimo Buencuerpo, John F. Geisz, Michelle S. Young, Talysa R. Klein, Adele C. Tamboli, Emily L. Warren
Summary: Strings constructed from three-terminal tandem (3TT) solar cells offer the performance benefits of voltage-matching, but the circuitry can become complex. The article illustrates the essential features of homogenous voltage-matched (VM) 3TT strings and discusses various configurations and construction of string I(V) curves. Mitigation strategies for reducing end losses intrinsic to these strings are also presented.
IEEE JOURNAL OF PHOTOVOLTAICS
(2021)
Article
Multidisciplinary Sciences
Alina LaPotin, Kevin L. Schulte, Myles A. Steiner, Kyle Buznitsky, Colin C. Kelsall, Daniel J. Friedman, Eric J. Tervo, Ryan M. France, Michelle R. Young, Andrew Rohskopf, Shomik Verma, Evelyn N. Wang, Asegun Henry
Summary: Thermophotovoltaics (TPVs) convert infrared light into electricity, enabling energy storage and conversion using high temperature heat sources. This study reports the fabrication and measurement of high-efficiency TPV cells, demonstrating the efficiency of high-bandgap tandem TPV cells.
Article
Optics
Fan Zhang, Jose F. Castaneda, Timothy H. Gfroerer, Daniel Friedman, Yong-Hang Zhang, Mark W. Wanlass, Yong Zhang
Summary: The authors demonstrate an all optical approach that allows for obtaining various key parameters relevant to carrier recombination dynamics in semiconductor materials. By analyzing photoluminescence and Raman measurements, they can determine parameters such as internal quantum efficiency, carrier density, and defect center occupation fraction. This method greatly enhances the usefulness of photoluminescence technique without the need for device processing and can be used for comprehensive material and device characterization.
LIGHT-SCIENCE & APPLICATIONS
(2022)
Article
Chemistry, Physical
Eric J. Tervo, Ryan M. France, Daniel J. Friedman, Madhan K. Arulanandam, Richard R. King, Tarun C. Narayan, Cecilia Luciano, Dustin P. Nizamian, Benjamin A. Johnson, Alexandra R. Young, Leah Y. Kuritzky, Emmett E. Perl, Moritz Limpinsel, Brendan M. Kayes, Andrew J. Ponec, David M. Bierman, Justin A. Briggs, Myles A. Steiner
Summary: Thermophotovoltaics is a promising solid-state energy converter with potential applications in grid-scale energy storage, concentrating solar-thermal power, and waste-heat recovery. Through good spectral management, optimized cell architecture, excellent material quality, and low series resistance, we have successfully designed, fabricated, and tested high-efficiency large-area thermophotovoltaic devices with an efficiency of up to 38.8% and an electrical power density of 3.78 W/cm(2) at a high emitter temperature of 1850℃.
Review
Energy & Fuels
Tao Song, Charles Mack, Rafell Williams, Daniel J. Friedman, Nikos Kopidakis
Summary: This article discusses the special performance measurement points and methods of perovskite multijunctions, including the measurement of spectral response, spectrum adjustment, and protocols for measuring the power output of the device at STC. It also presents common errors and pitfalls, as well as methods for evaluating data accuracy when a spectrally adjustable solar simulator is not available. Finally, performance measurement methods are recommended for high throughput situations.
Article
Multidisciplinary Sciences
Kaitlyn T. VanSant, Emily L. Warren, John F. Geisz, Talysa R. Klein, Steve Johnston, William E. McMahon, Henning Schulte-Huxel, Michael Rienaecker, Robby Peibst, Adele C. Tamboli
Summary: This study analyzes the performance of two superstrate 3T III-V-on-Si tandem solar cells and demonstrates that both cells exhibit the same efficiency, showing that the third terminal allows for flexibility in the selection of the top cell material, similar to the 4T design.
Article
Chemistry, Physical
William E. McMahon, John F. Geisz, Jeronimo Buencuerpo, Emily L. Warren
Summary: One design choice for constructing photovoltaic modules from tandem solar cells is whether to use 2-, 3-, or 4-terminal tandem devices. Two-terminal cells are the simplest to interconnect, but require current-matched subcells. Three-terminal cells can be interconnected in voltage-matched configurations, increasing the number of suitable subcell bandgap combinations, while four-terminal cells provide the best power production but have more complex interconnection requirements and shading losses.
SUSTAINABLE ENERGY & FUELS
(2023)
Article
Engineering, Electrical & Electronic
Theresa E. Saenz, John S. Mangum, Olivia D. Schneble, Anica N. Neumann, Ryan M. France, William E. McMahon, Jeramy D. Zimmerman, Emily L. Warren
Summary: We investigate the morphology and dislocation dynamics of GaP grown on a V-groove Si substrate using metalorganic vapor phase epitaxy (MOVPE). Si from the substrate stabilizes the (0 0 1) GaP facet, which is essential for successful coalescence. The size of the SiNx caps covering the V-grooves is crucial for maintaining the influence of Si on GaP coalescence. If the SiNx caps are too large, (1 1 1) diamond faceting occurs, preventing coalescence. Successful coalescence results in a root-mean-square roughness of 0.2 nm and a threading dislocation density of 5 x 107 cm-2. Dislocation glide is observed during coalescence through transmission electron microscopy. These GaP on V-groove templates have the potential for growth of III-V optoelectronic devices with reduced threading dislocation density.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
John F. Geisz, William E. McMahon, Jeronimo Buencuerpo, Michelle S. Young, Michael Rienacker, Adele C. Tamboli, Emily L. Warren
Summary: The study explores measurement techniques for multi-terminal photovoltaic devices, using specific examples to demonstrate characterization methods. The coupling mechanisms between subcells in tandem solar cells are quantified within a simple equivalent optoelectronic circuit, with electrical and optical coupling mechanisms revealed through dark measurements.
CELL REPORTS PHYSICAL SCIENCE
(2021)
Proceedings Paper
Energy & Fuels
Tao Song, Larry Ottoson, Josh Gallon, Daniel J. Friedman, Nikos Kopidakis
Summary: This paper emphasizes the importance of reliable performance calibration on large-size perovskite modules, proposing a protocol for Maximum Power Point Tracking (MPPT) and comparing it with Asymptotic PMAX. The interplay between metastability and degradation in perovskite modules is demonstrated using MPPT, highlighting the necessity to develop preconditioning protocols for stabilizing these devices. The goal is to promote the development of consensus protocols for performance calibration of perovskite modules to advance their credible power ratings in the PV market.
2021 IEEE 48TH PHOTOVOLTAIC SPECIALISTS CONFERENCE (PVSC)
(2021)
Proceedings Paper
Energy & Fuels
Nikos Kopidakis, Paul Ndione, Kyle Lu, Greg Horrner, Daniel Friedman
Summary: Measurements of the spectral response of cells in a PV module are essential for accurate calibration and understanding of the device's physics. A new approach for testing individual cells' spectral response in silicon modules allows for fast mapping of responses and reveals significant variations among different cells in a module. This variation has implications for the uncertainty of spectral correction and ISC calibration using a solar simulator.
2021 IEEE 48TH PHOTOVOLTAIC SPECIALISTS CONFERENCE (PVSC)
(2021)
Article
Chemistry, Physical
Shinjae Hwang, James L. Young, Rachel Mow, Anders B. Laursen, Mengjun Li, Hongbin Yang, Philip E. Batson, Martha Greenblatt, Myles A. Steiner, Daniel Friedman, Todd G. Deutsch, Eric Garfunkel, G. Charles Dismukes
SUSTAINABLE ENERGY & FUELS
(2020)