Advances in Solar Energy: An Annual Review of Research and Development

466 Pages·1989·15.705 MB·English

by  Yoshihiro Hamakawa, Hiroaki Okamoto (auth.), Karl W. Böer (eds.)

Advances in
Solar Energy
An Annual Review of
Research and Development
Volume 5
Editorial Board
Editor-in~Chief
Karl W. Boer
University of Delaware, Newark, Delaware
Associate Editors
Douglas J. Balcomb
Los Alamos National Laboratory, Los Alamos, New Mexico
Brian Brinkworth
University Col/ege, Cardi'" United Kingdom
Harry Bungay
Rensselaer Polytechnic Institute, Troy; New York
Kinsell Coulson
Mauna Loa Observatory, Hilo, Hawaii
John A. Duffie
University of Wisconsin at Madison, Madison, Wisconsin
Baruch Givoni
Ben Gurion University, Beersheba, Israel
Roger van Overstraeten
Katholieke Universiteit Leuven, Leuven, Belgium
Morton Prince
Department of Energy, Washington, D. C.
Michael Seibert
Solar Energy Research Institute, Golden, Colorado
Horst Selzer
Erno-Raumfahrttechnik GmbH, Bremen, Federal Republic of Germany
Bernard Serafin
University of Arizona, Tucson, Arizona
Steven Szokolay
University of Queensland, Queensland, Australia
Irwin Vas
Flo Wind Corporation, Kent, Washington
Donald Watson
Branford, Connecticut
A Continuation Order Plan is available for this series. A continuation order will bring delivery of each new
volume immediately upon publication. Volumes are billed only upon actual shipment. For further informa
tion please contact the publisher.
Advances in
Solar Energy
An Annual Review of
Research and Development
Volume 5
Edited by
Karl W. Boer
University of Delaware
Newark, Delaware
AMERICAN SOLAR ENERGY SOCIETY, INC.
Boulder, Colorado - Newark, Delaware
and
PLENUM PRESS
New York -London
The Library of Congress has cataloged this title as follows:
Advances in solar energy.-Vol. 1 (19821- -New York: American Solar Energy
Society, c1983-
v. ill.; 27 cm.
Annual.
=
ISSN 0731-8618 Advances in solar energy.
1. Solar energy - Periodicals. I. American Solar Energy Society.
TJ809.S38 621.47'06-dc19 ~250
MRC 2 MARC-S
Library of Congress [8603]
ISBN-I3:97S-I-4612-SI07·S e-ISBN-13:97S-1-4613 -OS37-9
001: 10.1007/97S-1-4613-0837-9
© 1989 Plenum Press, New York
Softcover reprint of the hardcover 1st edition 1989
A Division of Plenum Publishing Corporation
233 Spring Street, New York, N.Y. 10013
All rights reserved
No part of this book may be reproduced, stored in a retrieval system, or transmitted
in any form or by any means, electronic, mechanical, photocopying, microfilming,
recording, or otherwise, without written permission from the Publisher
FOREWORD
Advances in Solar Energy, now in its fifth year, is continuing with topics of
the main field of solar energy conversion. However, because of the increasing interest
in a solar systems approach, we have decided to include the article of Bockris et al.,
on Hydrogen Technology, which offers interesting aspects of transport and storage
of solar energy, as well as the potential for a versatile fuel.
The other articles cover the field of photovoltaics, solar energy-related mate
rials, wind conversion, solar retrofitting of existing buildings, and new architectural
designs in harmony with climate and the comfort of all occupants. These articles
give a critical assessment of the present state of the art, and provide a long list of
literature for further in-depth studies.
I greatly appreciate the assistance of the Editors and referees of the articles
for their many constructive suggestions.
My special thanks go to Ms. Martha Hobbs for her dedicated work in
typesetting the manuscript in the University of Delaware's Publication Office, and
to the University of Delaware for their continued support. The accommodating help
from Plenum Press and its production staff deserves our grateful acknowledgement.
Karl W. Boer
v
CONTENTS
Chapter 1 AMORPHOUS SILICON SOLAR CELLS 1
Yoshihiro Hamakawa and Hiroaki Okamoto
1.1 Introduction 1
1.2 Unique Advantages of Q-Si Solar Cell 4
1.2.1 High Optical Absorption and Large Photoconductivity in
the Visible Region 4
1.2.2 Existence of Valence Controllability 5
1.2.3 Large Area Non-epitaxial Growth on Any Foreign Substrate
Material at Low Temperature ................................ . 5
1.2.4 Large Scale Merit with High Mass Producibility ...•.............. 5
1.3 Structure and Electronic Density of States ..................... . 5
1.4 Fihn Deposition and Valency Control of Q-Si and Its Alloys 12
1.5 Carrier Transport and Drift Type Photolovtaic Effect in Q-Si 20
1.6 Characterization of Material and Junction Properties 34
1.6.1 Built-in Potential 34
1.6.2 Mobility-lifetime Product and Interface Property 37
1.6.3 Density of Gap States 43
1. 7 Key Technologies for Improving
Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
1.8 Heterojunction Solar Cell .. .. . .. .. . .. .. . .. .. . .. .. . .. .. . .. .. .. .. . 51
1.9 Q-Si Basis Stacked Solar Cell . . . . .. .. . . . . . . . . . . .. . . . . . . . . . .. . . . . 53
1.9.1 Photo-generated Current Continuity Rule 54
1.9.2 Absorption Coefficient Order Rule .•..•......•......•.........•• 57
1.10 Staebler-Wronski effect ......................................... 64
1.11 Light Induced Degradation of Q-Si Solar Cell ................... 70
vii
viii CONTENTS
1.12 Aspect of Application Systems ..... ..... ... . . ..... ..... ..... ... 81
1.13 Conclusion ........................................... , ........ 86
1.14 REFERENCES . . .. . . . . . . . .. . .. . . . . . . .. . .. . . . . . . . . . .. . . . . . . . .. 87
Chapter 2 ADVANCES IN SOLAR OPTICAL MATERIALS 99
Carl M. Lampert
2.1 Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 99
2.2 Introduction 100
2.3 Antireflection Films 101
2.4 Metallic Reflector Materials 106
2.5 Solar Selective Absorbers 108
2.5.1 Intrinsic Absorbers 111
2.5.2 Optical Trapping Surfaces 112
2.5.3 Semiconductor/Metal Tandems .•............••..........••.•. 115
2.5.3.1 Multilayer Absorbers ...••.•..•..••...••..•.......•.... 117
2.6 Radiative Cooling Materials .................................. 118
2.7 Transparent Low-Emittance Coatings 121
2.7.1 Multilayer Low-emittance Films 125
2.7.2 Highly Doped Semiconductor Films ........•.......... , ......• 126
2.7.3 MeshL.ow-emittance Coatings ........•....•.....• " .. , .....•. 130
2.8 Fluorescent Concentrators .................................... 131
2.9 Spectral Splitting and Cold Mirror Films ..................... 135
2.10 Transparent Aerogel and Poly-
meric Transparent Insulation .................................. 137
2.11 Optical Switching Materials and Devices ...................... 139
2.11.1 Photochromic Materials •..•.•....•..•..............•..••. , " 141
2.11.2 Thermochromic Materials ......................•............ 144
2.11.3 Liquid Crystals ................•...•..................•.... 145
2.11.4 Electrochromic Materials and Devices ......................... 145
2.12 Prismatic Light Guides ....................................... 148
2.13 Holographic Films ............................................ 151
2.14 Conclusions .................................................. 153
2.15 Acknowledgements 153
2.16 REFERENCES 153
Chapter 3 A SOLAR HYDROGEN ENERGY SYSTEM ....... 171
J .O'M Bockris, B. Dandapani and J .C. Wass
3.1 Introduction 171
3.1.1 Nuclear Fission Based Energy Supply 171
CONTENTS ix
3.1.2 Coal Based Energy Supply ......•..•.•...........•..•....... 173
3.1.3 Solar Energy as a General Energy Source ...........•.......... 177
3.2 Available Solar Energy ...................................... . .1 79
3.2.1 Is Solar Energy a Dilute Source? ............................ . 179
3.2.2 A History of the Concept of the Solar-Hydrogen Economy 182
3.2.3 Amount of Land Based Solar Energy Available ................ . 183
3.2.4 Other Areas Yielding Solar Energy .••........................ 188
3.2.5 The Change in the Status of Solar Energy as a Main Source of Energy
Due to the Introduction of Hydrogen as an Energy Medium 190
3.3 Direct Methods for Collecting Solar Energy .................. . 191
3.3.1 Solar Thermal Techniques 192
3.3.2 Photovoltaic Collection Systems 195
3.3.3 Photovoltaic Concentrator Systems 203
3.3.4 Environmental Effects of the Photovoltaic Systems ...•.......... 204
3.3.5 Other Collection Systems ..........•..•..................... 206
3.4 Indirect Solar Energy Collection ............................. . 209
3.4.1 Hydroelectric Potential in North America 209
3.4.2 Wind Energy Potential 213
3.4.3 Bioproduction of Hydrogen ...•...•...•.•.•.................. 222
3.5 Splitting of Water ........................................... . 224
3.5.1 Production of Hydrogen from Water . . . . . . . . . . . . . . . . . . . . • • . . .. 225
3.5.2 Other Approaches to the Splitting of Water . . . . . . . . . . . . . . . . . • .. 235
3.5.3 Novel Ideas in the Production of Hydrogen .•....•............. 245
3.6 Transmission of Hydrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 248
3.6.1 Hydrogen Transport Through Pipelines Over Long Distances 248
3.6.2 Cost of Transmission of Hydrogen .................•....•..... 249
3.6.3 Liquid Hydrogen Transmission Through Pipelines ............•.. 250
3.6.4 Marine Transportation ..........•.....•......•..........•... 251
3.6.5 Transport Through Sea Over Long Distances (Underwater
Pipelines) .......•.•........•........••..•...•........•... 251
3.6.6 Rail Transportation 251
3.6.7 Highway Transportation 251
3.6.8 Transportation in Cylinders and as Hydrides 252
3.7 Storage of Hydrogen 252
3.7.1 Pressure Cylinders ........................................ . 252
3.7.2 Above Ground Storage Tanks ........................•.....•. 253
3.7.3 Underground Storage of Hydrogen 253
3.7.4 Pipeline in Storage Systems 254
3.7.5 Hydrides 254
3.7.6 Microcavity Storage System ...........•....•................ 255
3.7.7 Zeolites ............•...........................•.......... 257
3.7.8 Storage by Conversion to Ammonia .......................... . 258
3.7.9 Chemical Closed Loop Cycle ................................ . 258
3.7.10 Metal-Aromatics and Transition Metal Complexes ...........•.. 258
3.7.11 Liquid Hydrogen .......................................... . 259
x CONTENTS
3.8 Present Uses of Hydrogen .................................... 260
3.8.1 Ammonia Synthesis .................•...........•.•.....•.. 260
3.8.2 Synfuel Production •.....•....................•...... " ..... 261
3.8.3 Petrochemical Industries ...•......•....•......•........•.... 262
3.8.4 Chemical Industries .....•..•..••...•...•.................•. 263
3.8.5 Fats and Oils ................•......••..................... 263
3.8.6 Pharmaceuticals ....••...•.....•.......•.....•........•.... 264
3.8.7 Metals Industries ........••......••.•.. , ..............•.... 264
3.8.8 Electronics ...••..•...•..•.•••••....••....•.......•..•...•. 265
3.8.9 Float Glass ............................................... 266
3.8.10 Total Small User Hydrogen Demand ..•......•..•......•...••. 266
3.9 Proposed Uses of Hydrogen ................................... 266
3.9.1 Space Research ......•...•....•.•.•.•..•..•................ 267
3.9.2 Sub-orbital Aircraft .•••..•.••..••.•.••.••••.••.•........... 267
3.9.3 Hydrogen Use for Air Transportation ...•••.....•.•.•.•....... 267
3.9.4 Hydrogen for Automotive Transportation ...•...•...........••. 269
3.9.5 Hydrogen Powered Train •....••......•.....••.•.•....•....•. 273
3.9.6 Other Uses •..••...•••••...••..••••..••••...••.•......•.... 274
3.9.7 Residential Uses of Hydrogen ......•..••••..••.••••••..••.... 274
3.9.8 Hazards of Hydrogen ..•.•...........•..•........•...•....•• 275
3.10 Projected Economics of Hydrogen Production ................. 277
3.10.1 Relevant Time Scale ....•...••..•....••••..••...•.••...•••.. 278
3.10.2 Fossil Fuels: The Economics of Pollution ......•....•.••.•.••.. 280
3.10.3 Hydrogen from Coal ..•.........•...•...........•.........•. 282
3.10.4 Electrolysis of Water ...•.........•........•...........•.... 286
3.10.5 Hydrogen from Direct Solar Sources •...••...•..•....••....... 290
3.10.6 Hydrogen from Indirect Solar Sources •............•........... 291
3.10.7 Summary of Costs ........•.•....•..•...................... 292
3.11 REFERENCES ......•.............•........•................ 293
Chapter 4 WIND TECHNOLOGY TODAY ..................... 306
D.M. Dodge and R.W. Thresher
4.1 Introduction .................................................. 306
4.1.1 Historical Summary ..•........••....••••..•. , •.•.....•..... 307
4.2 Analytical Design Theory ..................................... 308
4.2.1 Predicting Wind Inflow ..•••••..•••.....•.....•............. 308
4.2.2 Aerodynamics .......•..•......•.......•.....•.•.•.•.....•• 311
4.2.3 Predicting Structural Dynamic Loads •••••....•.•.••....••..•. 314
4.2.4 Yaw Dynamics ...••...•.....•...•.•••...•••...••..••••••.• 316
4.2.5 Wind Thrbine Fatigue and Fatigue Models ................ , .... 319
4.2.6 Wind Thrbine Safety and Reliability •......................... 321
4.3 Design Issues and Tradeoff's ................................... 322
4.3.1 Design Criteria .•..•....••••.•••.•....•....•...•.••..•.•..• 322
4.3.2 Rotor Design ••.•..•..••..••...•.••....•.......•••.••..••.. 322
CONTENTS xi
4.3.3 Blade Number 323
4.3.4 Operation Strategy 325
4.3.5 Rotor Orientation 326
4.3.6 Hub Design and Blade Articulation ....•.....••••....••..... 326
4.3.6.1 Airfoil Selection and Design ........•..•......•.••••.. 326
4.3.6.2 Blade Design .••...••.•••••..•.•.•••.•...•......•..• 328
4.3.7 Drive Train Configuration •..... , ... " •.••.....•.•........• 329
4.3.8 Electrical Power System ..•.........•.•.••..•....•.....•... 329
4.3.8.1 Constant Speed Generators ....•............•......•.. 329
4.3.8.2 Variable-Speed Generators .......•.....•.............. 330
4.3.8.3 Mechanical Power Converters ..•.•.•......•........... 331
4.4 Control Systems ........................................... . 331
4.4.1 Rotor Control 331
4.4.2 Electrical Control 332
4.4.3 System Control ..•..........•........•.............•....•. 332
4.4.4 Tower/Foundation Design .......•..........•..........•... 333
4.5 Current Wind Turbines and Their Performance ............ . 333
4.5.1 Commercial Wind Turbines 333
4.5.1.1 Horizontal-Axis Wind Turbines (HAWTs) .....•..•...... 333
4.5.1.1.1 Small HAWTs ••.•...•....•..•.....•.•.•.•...•. 333
4.5.1.1.2 Intermediate-Scale HAWTs .•..•..•....•.•...•.•. 335
4.5.1.2 Vertical-Axis Wind Turbines(VAWTs) •.....•........•.. 337
4.6 Experimental and Research Wind Turbines ................ . 338
4.7 Performance of Current Systems 340
4.8 Design and Reliability Problems .............................3 42
4.8.1 Blade and Rotor Failure 342
4.9 Drive Train and Electrical Problems 343
4.10 Yaw Drive 343
4.11 Tower Failures 343
4.12 Wind Power Resources, Applications and Economics ......... 344
4.12.1 Applications and Economics ..••....•.•.•...••••.••••..•••• 345
4.13 Public Acceptance of Wind Power Development ............ . 349
4.13.1 Public Nuisance and Aesthetic Issues 349
4.13.1.1 Visual Impact 349
4.13.1.2 Noise Impact 350
4.13.1.3 Acoustic Noise 350
4.13.1.4 Electromagnetic Interference ..•..•... " ...........•... 351
4.14 Environmental Impact Issues .............................. . 351
4.14.1 Land Use Issues 351
4.14.2 Impacts on Human Health and Biota 352
4.14.3 Impacts Compared to Other Energy Technologies 352
4.15 Current Research and Development Programs 353
4.15.1 Research in the United States 353