DOE/ER-0085 Dist. Categories UC-20e, 34b, 41,,63, 93, 97, 97a, 97d Program Assessment Report Statement of Findings Satellite Power Systems Concept Development and Evaluation Program November 1980 U.S. Department of Energy Office of Energy Research Solar Power Satellite Project Division Washington, D.C. 20545 DOE/NASA SATELLITE POWER SYSTEM Concept Development and Evaluation Program CONTENTS • EXECUTIVE SUMMARY . • • • • • • • • • • • • • • • • • • • • • • • • V1 • • • SCOPE • . • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • . • Vl 11 1 INTRODUCTION • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 1 1.1 Potential of Solar Energy in Space ••••••••.. • • • • • • • • • • 1 1.2 General SPS Concept • . • • • . • • • • • . • • • • • • • • • • • • • • 1 1.3 Concept Potential . • . • . • . • . • . • • • • • • • • • • 1 1.4 CDEP Objectives and Questions .••.••••••.... • • • • • • • • 1 2 SPS SYSTEM CONCEPTS • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 3 2.1 SPS Reference System. • . • . • • • • • • . " . • • • • • • • • 3 2.2 SPS Alternative System Concepts . • • • • • • • • • • • • • • • • • • • 4 3 STATEMENT OF FINDINGS •... • • • • • • • • • • • • • • • • • • • • • • • • • 8 3.1 Introduction. • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 8 3.2 Environmental Assessment ... • • • • • • • • • • • • • • • • • • • • • • 9 3.2.1 Background . •.. • • • • • • • • 9 3.2.2 Microwave Effects on Health and Ecosystems . • • • • • • • • • • • 9 3.2.3 Space Worker Health and Safety • . • . • • • • • • • • • • • 13 3.2.4 Atmospheric, Effects. • • . • . • . • . • • • • • • • • 18 3.2.5 Geostationary Orbit Allocation . • . • . • • • • • • • • 24 3.2.6 Effects on Astronomy . • . • . • . • . • • • • • • • • • • 24 3.3 Societal Assessment . • • • • • • • • • • • • • • • • • • • • 28 3.3.1 Background . • • • • • • • • • • • • • • • • • • • • • • • • • • • 29 3.3.2 Resources. • • • • • • • • . " . • • 29 3.3.3 Institutional Issues . • • • • • • • • • • • • • • • • • • • • 31 3.3.4 International Issues . • • • • • • • • • • • • • • • • • • • • • • 31 3.3.5 Public Concerns ••... • • • • • • • • • • • • • • • • • • • • • 33 3.3.6 Summary ..... • • • • • • • • • • • • • • • • • • • • • • • • 34 3.4 Comparative Assessment. • • • • • • • • • • • • • • • • • • • • • • • • • 34 3 .4 .1 Background . • • . • • . • • • • • • • • • • • • • • • • • • 34 3.4.2 Cost and Performance . • • • . " • • • • • • • • • • • 36 3.4.3 Environmental Welfare. • • • • • • • • • • • • • • • • • • • • • 38 3.4.4 Resources ••..•.•.. • • • • • • • • • • • • • • • • • • • • 39 3.4.5 Institutional Considerations • . • • • • • • • • • • • • • • • • 39 3.4.6 Heal th and Safety. • • • • • • • • • • • • • • • • • • • • • • 39 3.4.7 Summary Findings • • • • • • • . • • • • • • • • • • • • • • • • • 40 3.5 Systems Definition. • • • • • • • • • • • • • • • • • • • • • • • • • • • 41 3.5.1 Bae kground . 41 3.5.2 Solar Energy Conversion and On-Board Power Distribution. • . • 42 3.5.3 Power Transmission and Reception • • • • • . • • • • • • • • • • . 44 3.5.4 Space Structures, Controls and Materials ...•.•.•.•••. 46 3.5.5 Construction, Operation, and Maintenance ........•..•. 48 3.5.6 Space Transportation . .. 50 • • • 111 CONTENTS (Cont'd) APPENDIX A: HISTORICAL BACKGROUND ..•... • • • • • • • • • • • • • • • • • • 53 APPENDIX B: CDEP ASSESSMENT PROCESS .. • • • • • • • • • • • • • • • • • • • • • 56 APPENDIX C: CHARACTERISTICS OF THE SPS REFERENCE SYSTEM. • • • • • • • • • • • • • 61 APPENDIX D: REFERENCES . • • • • • • • • • • • • • • • • • • • • • • • • • • • • 64 APPENDIX E: ACRONYMS AND DEFINITIONS • • • • • • • • • • • • • • • • • • • • • • 67 FIGURES• 2.1 Satellite Power System Concept . • . • . • . • . • 3 2.2 Some Alternative Systems Concepts Employing Microwave Power Transmission . 5 2.3 Some Alternative Systems Concepts Employing Multiple Microwave Antennae. • . 6 2.4 Example of Reduction in Rectenna Size with Increased Power Density • • • • • 7 3.1 SPS Microwave Power Density Characteristics at a Reference System Rec tenna Site. • • • • • • • • 10 3.2 Factors Pertinent to Space Worker Health and Safety • • • • • • • • • • • • 14 3.3 Regions of the Atmosphere and Potential SPS Effects • • • • • • • • • • • • 20 3.4 Examples of SPS Microwave Transmission Effects on the Ionosphere and Telecommunication Systems .......•............. • • • • • 21 3.5 Levelized Life-Cycle Cost of Electricity . • • • • • • • • • • • • • • • • • 37 3.6 Distribution of Front-End Costs ••. • • • • • • • • • • • • • • • • • • • • 38 3.7 Quantified Health Effects ... • • • • • • • • • • • • • • • • • • • • • • • 40 B. l SPS Functional Organization. • • • • • • • • • • • • • • • . " 56 B.2 SPS Participatory Technology Process . • • • • • • • • • • • • • • • 58 B.3 CDEP Assessment Information Organization . • • • • • • • • • • • • • • • • • 59 C.l SPS Reference System • • . • . • • • . • • • • • • • • • • • • • • • • • • 61 TABLES 3.1 Effects o_f Microwave Exposure on Health and Ecosystems • • • • • • • • • • 12 3.2 Effects on Space Workers • • • • • • • • • • • • • • • • • • • • • • • • • 18 3.3 Atmospheric Effects. • • • • • • • • • • • • • • • • • • • • • • • • • 25 3.4 Geostationary Orbit Allocation . • • • • • • • • • • • • • • • • • • • • • 26 3.5 Effects on Astronomy . • • • • • • • • • • • • • • • • • • • • • • • • • • 29 3.6 Societal Assessment .. • • • • • • • • • • • • • • • • • • • • • • • • • • 35 1V• TABLES (Cont'd) 3.7 Capital Cost Ranges .. • • • • • • • • • • • • • • • • • • • • • • • • • • 36 3.8 Water Requirements for Alternative Energy Technologies • . • • • • • • • • 39 3.9 Unquantified Health Effects •.•.. • • • • • • • • • • • • • • • • • • • 41 3 .10 Solar Energy Conversion and On-Board Power Distribution •• • • • • • • • • 44 3.11 Power Transmission and Reception • • • • • • • • • • • • • • • • • • • • • 47 3.12 Space Structures, Controls, and Materials . • • • • • • • • • • • • • • • • 49 ' 3.13 Construction, Operation, and Maintenance. • • • • • • • • • • • • • • • • • 51 3.14 Space Transportation. • • • • • • • • • • • • • • • • • • • • • • • • • • • 52 B.l Key Organizations • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 57 B.2 CDEP Budget· • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 59 C.l Reference System Characteristics •. • • • • • • • • • • • • • • • • • • • • 62 v EXECUTIVE SUMMARY PREFACE examined more thoroughly by the National Aeronautics and Space Administration This report states what is known, (NASA), the Department of Energy (DOE), uncertain, and unknown about the Solar academia, and industry. In 1976, on the Power Satellite ( SPS), concept-­ basis that the SPS is an energy option, collecting solar energy in space and the Office of Management and Budget delivering the energy to Earth for the (OMB) assigned the responsibility for production of baseload electricity. the evaluation of the SPS to the Energy Research and Development Administration This report fulfills the objective of (ERDA), the predecessor of DOE. In the Satellite Power System Concept 1977, DOE and NASA started a three-year Development and Evaluation Program Concept Development and Evaluation (CDEP) "to develop, by the end of 1980, Program. an initial understanding of the techni­ cal feasibility, the economic practical­ The CDEP was implemented because the ity, and the social and environmental SPS concept appeared to have the fol­ acceptabi 1 i ty of the SPS concept." lowing attributes that would be de­ sirable in any future energy option: This report discusses the important technical, environmental, and cost • The SPS could provide contin­ goal questions that must be answered uous baseload electricity. prior to making a commitment to the SPS c oncept. Although significant • The SPS would use an inexhaustible technological, environmental and econo­ energy source--the Sun. mic questions remain to be answered, the • The SPS is international in scope, preliminary investigations undertaken in c apable of providing energy for the CDEP do provide a basis for a policy domestic and world markets. decision on further commitment. The SPS Reference System was designed This report also suggests areas of to serve• as a mechanism• to assess the research and experimentation required to environmental and social aspects of the acquire the knowledge by which a series concept and to provide a basis for of informed, time-phased decisions may comparison with alternative concepts. be made concerning the possibility of Technologically, it does not represent the SPS concept playing a major role in an optimal or preferred system. System the United States' energy future. definition studies of plausible alterna­ tives to the SPS Reference System would be required to arrive at a preferred DISCUSSION system. Such activity could, if pur­ sued, be linked to current DOE and NASA Systems Definition generic research in fields of energy c onvers 1on,• spac e transportation,• For the past 20 years, photovoltaic structures and materials, and space energy conversion systems in space have construction. Areas of research speci­ powered communication, earth resource, fic to an SPS preferred system would and meteorological satellites, planetary include microwave power generation, probes and manned spacecraft. During transmi ssion, control and reception; this period, the remote transmission of space-to-earth laser power transmission power by means of microwaves was demon­ and reception; and research associated strated. In 1968, . the two ideas were with large-size