Photon Management in Solar Cells E-Book

• Herausgeber: Wiley-VCH
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 744

Veröffentlichungsjahr: 2015

Beschreibung

Written by renowned experts in the field of photon management in solar cells, this one-stop reference gives an introduction to the physics of light management in solar cells, and discusses the different concepts and methods of applying photon management.
The authors cover the physics, principles, concepts, technologies, and methods used, explaining how to increase the efficiency of solar cells by splitting or modifying the solar spectrum before they absorb the sunlight. In so doing, they present novel concepts and materials allowing for the cheaper, more flexible manufacture of solar cells and systems.
For educational purposes, the authors have split the reasons for photon management into spatial and spectral light management.
Bridging the gap between the photonics and the photovoltaics communities, this is an invaluable reference for materials scientists, physicists in industry, experimental physicists, lecturers in physics, Ph.D. students in physics and material sciences, engineers in power technology, applied and surface physicists.

Leseprobe

Table of Contents

Cover

Title Page

Related Titles

Copyright

Preface

List of Contributors

Chapter 1: Current Concepts for Optical Path Enhancement in Solar Cells

1.1 Introduction

1.2 Planar Antireflection Coatings

1.3 Optical Path Enhancement in the Ray Optical Limit

1.4 Scattering Structures for Optical Path Enhancement

1.5 Resonant Structures for Optical Path Enhancement

1.6 Ultra-Light Trapping

1.7 Energy-Selective Structures as Intermediate Reflectors for Optical Path Enhancement in Tandem Solar Cells

1.8 Comparison of the Concepts

1.9 Conclusion

References

Chapter 2: The Principle of Detailed Balance and the Opto-Electronic Properties of Solar Cells

2.1 Introduction

2.2 Opto-Electronic Reciprocity

2.3 Connection to Other Reciprocity Theorems

2.4 Applications of the Opto-Electronic Reciprocity Theorem

2.5 Limitations to the Opto-Electronic Reciprocity Theorem

2.6 Conclusions

References

Chapter 3: Rear Side Diffractive Gratings for Silicon Wafer Solar Cells

3.1 Introduction

3.2 Principle of Light Trapping with Gratings

3.3 Fundamental Limits of Light Trapping with Gratings

3.4 Simulation of Gratings in Solar Cells

3.5 Realization

3.6 Topographical Characterization

3.7 Summary

References

Chapter 4: Randomly Textured Surfaces

4.1 Introduction

4.2 Methodology

4.3 Properties of an Isolated Interface

4.4 Single-Junction Solar Cell

4.5 Intermediate Layer in Tandem Solar Cells

4.6 Conclusions

Acknowledgments

References

Chapter 5: Black Silicon Photovoltaics

5.1 Introduction

5.2 Optical Properties and Light Trapping Possibilities

5.3 Surface Passivation of Black Silicon

5.4 Black Silicon Solar Cells

References

Chapter 6: Concentrator Optics for Photovoltaic Systems

6.1 Fundamentals of Solar Concentration

6.2 Optical Designs

6.3 Silicone on Glass Fresnel Lenses

6.4 Considerations on Concentrators in HCPV Systems

6.5 Conclusions

References

Chapter 7: Light-Trapping in Solar Cells by Directionally Selective Filters

7.1 Introduction

7.2 Theory

7.3 Filter Systems

7.4 Experimental Realization

7.5 Summary and Outlook

References

Chapter 8: Linear Optics of Plasmonic Concepts to Enhance Solar Cell Performance

8.1 Introduction

8.2 Metal Nanoparticles

8.3 Surface-Plasmon Polaritons

8.4 Front-Side Plasmonic Nanostructures

8.5 Rear-Side Plasmonic Nanostructures

8.6 Further Concepts

8.7 Summary

Acknowledgments

References

Chapter 9: Up-conversion Materials for Enhanced Efficiency of Solar Cells

9.1 Introduction

9.2 Up-Conversion in Er

3+

-Doped ZBLAN Glasses

9.3 Up-Conversion in Er

3+

-Doped β-NaYF

4

9.4 Simulating Up-Conversion with a Rate Equation Model

9.5 Increasing Up-Conversion Efficiencies

9.6 Conclusion

Acknowledgments

References

Chapter 10: Down-Conversion in Rare-Earth Doped Glasses and Glass Ceramics

10.1 Introduction

10.2 Physical Background

10.3 Down-Conversion in ZBLAN Glasses and Glass Ceramics

10.4 Down-Conversion in Sm-Doped Borate Glasses for High-Efficiency CdTe Solar Cells

10.5 Summary

Acknowledgment

References

Chapter 11: Fluorescent Concentrators for Photovoltaic Applications

11.1 Introduction

11.2 The Theoretical Description of Fluorescent Concentrators

11.3 Materials for Fluorescent Concentrators

11.4 Experimentally Realized Fluorescent Concentrator Systems

11.5 Conclusion

Acknowledgments

References

Chapter 12: Light Management in Solar Modules

12.1 Introduction

12.2 Fundamentals of Light Management in Solar Modules

12.3 Technological Solutions for Minimized Optical Losses in Solar Modules

12.4 Outlook

References

Index

End User License Agreement

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Guide

Cover

Table of Contents

Preface

Begin Reading

List of Illustrations

Figure 1.1

Figure 1.2

Figure 1.3

Figure 1.4

Figure 1.5

Figure 1.6

Figure 1.7

Figure 1.8

Figure 1.9

Figure 1.10

Figure 2.1

Figure 2.2

Figure 2.3

Figure 2.4

Figure 2.5

Figure 2.6

Figure 2.7

Figure 2.8

Figure 3.1

Figure 3.2

Figure 3.3

Figure 3.4

Figure 3.5

Figure 3.6

Figure 3.7

Figure 3.8

Figure 3.9

Figure 3.10

Figure 3.11

Figure 3.12

Figure 3.13

Figure 3.14

Figure 3.15

Figure 3.16

Figure 3.17

Figure 3.18

Figure 4.1

Figure 4.2

Figure 4.3

Figure 4.4

Figure 4.5

Figure 4.6

Figure 4.7

Figure 4.8

Figure 5.1

Figure 5.2

Figure 5.3

Figure 5.4

Figure 5.5

Figure 5.6

Figure 5.7

Figure 5.8

Figure 5.9

Figure 5.10

Figure 5.11

Figure 5.12

Figure 5.13

Figure 5.14

Figure 5.15

Figure 5.16

Figure 5.17

Figure 5.18

Figure 5.19

Figure 5.20

Figure 5.21

Figure 5.22

Figure 6.1

Figure 6.2

Figure 6.3

Figure 6.4

Figure 6.5

Figure 6.6

Figure 6.7

Figure 6.8

Figure 6.9

Figure 6.10

Figure 6.11

Figure 6.12

Figure 6.13

Figure 6.14

Figure 6.15

Figure 6.16

Figure 6.17

Figure 6.18

Figure 7.1

Figure 7.2

Figure 7.3

Figure 7.4

Figure 7.5

Figure 7.6

Figure 7.7

Figure 7.8

Figure 7.9

Figure 7.10

Figure 7.11

Figure 7.12

Figure 8.1

Figure 8.2

Figure 8.3

Figure 8.4

Figure 9.1

Figure 9.2

Figure 9.3

Figure 9.4

Figure 9.5

Figure 9.6

Figure 9.7

Figure 9.8

Figure 9.9

Figure 9.10

Figure 9.11

Figure 9.12

Figure 9.13

Figure 9.14

Figure 9.15

Figure 9.16

Figure 10.1

Figure 10.2

Figure 10.3

Figure 10.4

Figure 10.5

Figure 10.6

Figure 10.7

Figure 10.8

Figure 10.9

Figure 10.10

Figure 10.11

Figure 10.12

Figure 10.13

Figure 10.14

Figure 10.15

Figure 10.16

Figure 10.17

Figure 10.18

Figure 10.19

Figure 10.20

Figure 11.1

Figure 11.2

Figure 11.3

Figure 11.4

Figure 11.5

Figure 11.6

Figure 11.7

Figure 11.8

Figure 11.9

Figure 11.10

Figure 11.11

Figure 11.12

Figure 11.13

Figure 11.14

Figure 11.15

Figure 11.16

Figure 11.17

Figure 11.18

Figure 11.19

Figure 11.20

Figure 11.21

Figure 12.1

Figure 12.2

Figure 12.3

Figure 12.4

Figure 12.5

List of Tables

Table 1.1

Table 5.1

Table 5.2

Table 9.1

Table 10.1

Edited byRalf B. Wehrspohn, Uwe Rau, and Andreas Gombert

Photon Management in Solar Cells

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The Editors

Prof. Dr. Ralf B. Wehrspohn

Martin Luther University

Institute of Physics

Heinrich-Damerow-Str. 4

06120 Halle

Germany

and

Fraunhofer-Institute for Mechanics of Materials IWM

Walter-Hülse-Strasse 1

06120 Halle

Germany

Prof. Dr. Uwe Rau

Research Center Jülich

IEF5-Photovoltaics

Leo-Brandt-Straße

52428 Jülich

Germany

Dr. Andreas Gombert

Soitec Solar GmbH

Bötzinger Str. 31

79111 Freiburg

Germany

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Preface

This edition on photon management in solar cells gives a comprehensive overview of the current state-of-the-art of the tricks in optics and photonics to increase the absorption of light in a solar cell. The ultimate aim is to have a really black solar cell. If we currently look around in the landscape, we still see reddish thin-film solar cell based on amorphous silicon or bluish solar cells based on multi-crystalline silicon. So there is still plenty of work to do to improve the current solar cell technology. And this becomes even more important for future silicon solar cells where the thickness of indirect band-gap absorber silicon shrinks to less than 100 µm. However, the spectrum that we see with our eye is not equivalent to the spectrum of the sun. There are, for example, about 20% of the photons in the infrared spectral range. If our eyes would see only the infrared spectral range of the sun below the band-gap of silicon, all the current silicon solar cells would look white! Thus, we are still far away from having really black silicon solar cells. The educated reader might ask if it is theoretically possible to have a completely black silicon solar cell and we would have to answer – no. We have to allow for a little bit of light by the radiative emission of the silicon solar cell. However, this can be managed in principle so that it only sees the small angle of the sun. Then, the solar cell radiative emission “sees” only itself and the sun. This is, in principle, the thermodynamic limit of the system solar cell and of the really black solar cell.

With the following contribution we wish to provide the reader with a lot of insights in the concept of photon management in solar cells, technical help for their current work, or just fun reading how a really black solar cell could be made. We like to thank A.N. Sprafke for helping us to edit the book.

Ralf B. Wehrspohn, Andreas Gombert, U. Rau

List of Contributors

Bernd Ahrens

Fraunhofer Center for Silicon Photovoltaics CSP

Walter-Hülse-Str. 1

06120 Halle (Saale)

Germany

and

Martin Luther University of Halle-Wittenberg

Centre for Innovation Competence SiLi-nano®

Karl-Freiherr-von-Fritsch-Str. 3

06120 Halle (Saale)

Germany

Katharina Baumgartner

Forschungszentrum Jülich GmbH

Institut für Energie- und Klimaforschung (IEK-5)

52425 Jülich

Germany

Thomas Beckers

Imperial College London

Department of Physics and Center for Plastic Electronics

South Kensington Campus

SW7 2AZ London

United Kingdom

Pablo Benitez

Universidad Politecnica de Madrid

E.T.S. de Ingenieros de Telecomunicacion

Cedint, Campus de Montegancedo

28233, Pozuelo

Madrid

Spain

Astrid Bingel

Friedrich Schiller University Jena

Abbe Center of Photonics

Institute of Applied Physics

Max-Wien-Platz 1

07743 Jena

Germany

Karsten Bittkau

Forschungszentrum Jülich GmbH

Institut für Energie- und Klimaforschung (IEK-5)

52425 Jülich

Germany

Benedikt Bläsi

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Andreas Büchtemann

Fraunhofer-Institut für Angewandte Polymerforschung IAP

Postfach 600 651

14406 Potsdam

Germany

Reinhard Carius

Forschungszentrum Jülich GmbH

Institut für Energie- und Klimaforschung

(IEK-5)

52425 Jülich

Germany

Dmitry N. Chigrin

RWTH Aachen University

Institute of Physics (IA)

Department of Physics

Templergraben 55

52056 Aachen

Germany

Marcel Dyrba

Fraunhofer Center for Silicon Photovoltaics CSP

Walter-Hülse-Str. 1

06120 Halle (Saale)

Germany

and

Martin Luther University of Halle-Wittenberg

Centre for Innovation

Competence SiLi-nano®

Karl-Freiherr-von-Fritsch-Strasse 3

06120 Halle (Saale)

Germany

Markus Ermes

Forschungszentrum Jülich GmbH

Institut für Energie- und Klimaforschung (IEK-5)

52425 Jülich

Germany

Stephan Fahr

Friedrich-Schiller-Universität Jena

Institute of Condensed Matter Theory and

Solid State Optics

Abbe Center of Photonics

Max-Wien-Platz 1

07743 Jena

Germany

Stefan Fischer

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Kevin Füchsel

Friedrich-Schiller-Universität Jena

Institute of Condensed Matter Theory and

Solid State Optics

Abbe Center of Photonics

Max-Wien-Platz 1

07743 Jena

Germany

and

Fraunhofer Institute of Applied Optics and Precision Engineering IOF

Albert-Einstein-Strasse 7

07745 Jena

Germany

Andreas Gerber

Forschungszentrum Jülich GmbH

Institut für Energie- und Klimaforschung (IEK-5)

52425 Jülich

Germany

Jan Christoph Goldschmidt

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Andreas Gombert

Soitec Solar GmbH

Bötzinger Str. 31

79111 Freiburg

Germany

Johannes Gutmann

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Florian Hallermann

RWTH Aachen University

Institute of Physics (IA)

Department of Physics

Templergraben 55

52056 Aachen

Germany

Hubert Hauser

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Christian Helgert

Friedrich-Schiller-Universität Jena

Abbe Center of Photonics

Institute of Applied Physics

Max-Wien-Platz 1

07743 Jena

Germany

Barbara Herter

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Thorsten Hornung

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Jacqueline Anne Johnson

University of Tennessee Space Institute

Department of Mechanical

Aerospace and Biomedical Engineering

411 B.H. Goethert Parkway

Tullahoma, TN 37388

USA

Thomas Käsebier

Friedrich Schiller University Jena

Abbe Center of Photonics

Institute of Applied Physics

Max-Wien-Platz 1

07743 Jena

Germany

Thomas Kirchartz

Imperial College London

Department of Physics and Center for Plastic Electronics

South Kensington Campus

SW7 2AZ London

United Kingdom

Ernst-Bernhard Kley

Friedrich Schiller University Jena

Abbe Center of Photonics

Institute of Applied Physics

Max-Wien-Platz 1

07743 Jena

Germany

Matthias Kroll

Friedrich Schiller University Jena

Abbe Center of Photonics

Institute of Applied Physics

Max-Wien-Platz 1

07743 Jena

Germany

Deepu Kumar

RWTH Aachen University

Institute of Physics (IA)

52056 Aachen

Germany

Falk Lederer

Friedrich-Schiller-Universität Jena

Institute of Condensed Matter Theory and Solid State Optics

Abbe Center of Photonics

Max-Wien-Platz 1

07743 Jena

Germany

Alexander Mellor

Universidad Politécnica de Madrid

Institúto de Energıa Solar

Avenida Complutense 30

28040 Madrid

Spain

Paul-Tiberiu Miclea

Fraunhofer Center for Silicon Photovoltaics CSP

Walter-Hülse-Str. 1

06120 Halle (Saale)

Germany

Juan C. Miñano

light prescriptions innovators (LPI)

2400 Lincoln Ave,

Altadena, CA 91001

USA

Martin Otto

Martin-Luther-Universität Halle-Wittenberg

Institute of Physics

Heinrich-Damerow-Str. 4

06120 Halle

Germany

Christian Paßlick

Martin Luther University of Halle-Wittenberg

Centre for Innovation Competence SiLi-nano®

Karl-Freiherr-von-Fritsch-Str. 3

06120 Halle (Saale)

Germany

Thomas Pertsch

Friedrich Schiller University Jena

Abbe Center of Photonics

Institute of Applied Physics

Max-Wien-Platz 1

07743 Jena

Germany

Marius Peters

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Liv Prönneke

Universität Stuttgart

Institut für Photovoltaik

Pfaffenwaldring 47

70569 Stuttgart

Germany

Uwe Rau

Institut für Energie- und Klimaforschung 5 - Photovoltaik

Forschungszentrum Jülich GmbH

Wilhelm-Johnen-Straße

52425 Jülich

Germany

Carsten Rockstuhl

Karlsruher Institut för Technologie

Institut für Theoretische Festkörperphysik

Wolfgang-Gaede-Str. 1

76128 Karlsruhe

Germany

Jens Schneider

Fraunhofer Center for Silicon Photovoltaics CSP

Otto-Eißfeldt-Street 12

06120 Halle

Germany

Isolde Schwedler

Fraunhofer Center for Silicon Photovoltaics CSP

Otto-Eißfeldt-Street 12

06120 Halle

Germany

Stefan Schweizer

Fraunhofer Center for Silicon Photovoltaics CSP

Walter-Hülse-Str. 1

06120 Halle (Saale)

Germany

and

South Westphalia University of Applied Sciences

Department of Electrical

Engineering

Lübecker Ring 2

59494 Soest

Germany

and

Fraunhofer Application Center for Inorganic Phosphors

Branch Lab of Fraunhofer Institute for Mechanics of Materials IWM

Lübecker Ring 2

59494 Soest

Germany

Gerhard Seifert

Fraunhofer Center for Silicon Photovoltaics CSP

Otto-Eißfeldt-Street 12

06120 Halle

Germany

Alexander N. Sprafke

Martin Luther University Halle-Wittenberg

Institute of Physics

Heinrich-Damerow-Str. 4

06120 Halle

Germany

Martin Steglich

Friedrich Schiller University Jena

Abbe Center of Photonics

Institute of Applied Physics

Max-Wien-Platz 1

07743 Jena

Germany

Lorenz Steidl

Johannes Gutenberg University Mainz

Institute of Organic Chemistry

Duesbergweg 10-14

55099 Mainz

Germany

Heiko Steinkemper

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Franziska Steudel

Fraunhofer Center for Silicon Photovoltaics CSP

Walter-Hülse-Strasse 1

06120 Halle (Saale)

Germany

Andreas Tünnermann

Friedrich Schiller University Jena

Abbe Center of Photonics

Institute of Applied Physics

Max-Wien-Platz 1

07743 Jena

Germany

and

Fraunhofer Institute of Applied Optics and Precision Engineering IOF, Albert-Einstein-Strasse 7

07745 Jena

Germany

Carolin Ulbrich

Forschungszentrum Jülich GmbH

Institut für Energie- und Klimaforschung (IEK-5)

52425 Jülich

Germany

Johannes Üpping

Martin-Luther-University Halle-Wittenberg

Institute of Physics

Heinrich-Damerow-Str. 4

06120 Halle

Germany

Gero von Plessen

Physikalisches Institut

RWTH Aachen

52056 Aachen

Germany

Armin Wedel

Fraunhofer-Institut für Angewandte Polymerforschung IAP

Postfach 600 651

14406 Potsdam

Germany

Ralf B. Wehrspohn

Martin Luther Universität Halle-Wittenberg

Institute of Physics

Heinrich-Damerow-Str. 4

06120 Halle

Germany

and

Fraunhofer Institute for Mechanics of Materials (IWMH)

Walter-Hülse-Strasse 1

06120 Halle

Germany

Marie-Christin Wiegand

Fraunhofer-Center für Silizium-Photovoltaik CSP

Walter-Hülse-Str. 1

06120 Halle (Saale)

Germany

Samuel Wiesendanger

Friedrich-Schiller-Universität Jena

Institut für Festkörpertheorie und -optik

Max-Wien-Platz 1

07743 Jena

Germany

Sebastian Wolf

Fraunhofer Institute for Solar Energy Systems

Solar Thermal and Optics

Heidenhofstraße 2

79110 Freiburg

Germany

Rudolf Zentel

Johannes Gutenberg University Mainz

Institute of Organic Chemistry

Duesbergweg 10-14

55099 Mainz

Germany

1Current Concepts for Optical Path Enhancement in Solar Cells

Alexander N. Sprafke and Ralf B. Wehrspohn

1.1 Introduction

The conversion efficiency of a solar cell, that is, the ratio of electrical power extracted from the cell to the power of solar photons flowing into the cell, is directly connected to the number of photons absorbed in the absorber material of the cell. Therefore, it is of critical importance to insert as many photons as possible into the cell and keep them inside the cell until they are finally absorbed. While achieving the first aspect is referred to as antireflection, the second aspect is commonly called optical path enhancement, also known as light Trapping, which is the focus of this chapter.

Because of its fundamental significance to the solar-to-electrical conversion mechanism, light trapping should be considered for any solar absorber material. However, light trapping is of particular importance for solar cells based on crystalline silicon (c-Si). Owing to its abundance and to the long-existing mature technologies in the electronic industry, commercial c-Si based solar cells are widely available and dominate the PV market today [1]. But since c-Si is an indirect semiconductor, it is actually a relatively bad light absorber. Figure 1.1 shows the absorption depth of c-Si. of an absorbing material is defined as the distance at which the intensity of light decreases to after it enters the material. For wavelengths , most of the light energy is absorbed within a micron. For longer wavelengths, increases rapidly (note the logarithmic y-axis) and reaches values in the range of centimeters for wavelengths in the spectral range of the bandgap of c-Si at around .

Figure 1.1 Absorption depth of crystalline silicon plotted against the wavelength of light. The optical properties to calculate were taken from Ref. [2].