commercial power from space need

Dr. David R. Criswell Copyright 1996 (UH/TSGC: CPS DESIGN COURSES) 8/11/96

COMMERCIAL POWER FROM SPACE

NEED

The Texas Space Grant Consortium recognizes the need to provide each person on Earth, by2050, with at least 2 kilowatts of clean solar-electric power (2 kWe/person). In 2050 the 2kWe/person will likely enable as high a standard of living as is now achieved in Europe using 6kWt/person of thermal power (Wt) but without the pollution and depletion of resources thatresult from using fossil fuels to generate electric power. The global goal is to provide 10 billionpeople in 2050 a total of 20,000 billion watts of electric power (20,000 GWe). This power mustbe clean, safe, reasonably priced, widely available, stable in supply, have further growth potential,and enhance rather than deplete Earth’s resources and environment.

TSGC STUDIES OF THE LUNAR SOLAR POWER SYSTEM

TSGC will focus studies on the proposed Lunar Solar Power System. The LSP System collectsthe solar power on the moon, converts the solar power to beams of microwaves, directs the beamto receivers (called rectennas) on Earth, and then converts the microwaves to electricity for useon Earth.

TSGC focuses on the moon and the LSP System for several fundamental reasons.

1. The moon exists; it receives completely predictable solar power; utilization of only a smallfraction of the solar power incident on the moon could provide the Earth with adequatecommercial power for centuries.

2. Humans have been to the moon and returned samples and data; we understands its keyfeatures relative to solar power collection and transmission.

3. A Lunar Solar Power System Reference Model, research literature, and data bases exist thatenable many systems and focused design studies to be started immediately.

4. The LSP System components on the moon are to be built primarily from lunar materials ratherthan deployed from Earth. Factories are sent to the moon that output several hundred times,or more, their own mass as solar collectors and transmitters. This leverage greatly reduces thecost of space transporation per unit of energy delivered to Earth. Also, manufacturing usinglunar resources establishes a wide range of design studies that go well beyond those normallyassociated with aerospace. There are many opportunities for cooperation between designclasses that work over a wide range of disciplines. In addition, many challenging masters anddoctoral research topics are posed for deeper study.


5. The rectennas on Earth will be major construction projects. They are anticipated to havemajor economic and environmental benefits. Rectennas create many opportunities for studiesin environmental aspects of clean energy, business, finance, economic development of energy-poor areas, national and international legal issues and goverment cooperation, and studies ofthe transition of the world economy from a thermal to an electrical energy basis.

6. Even a small LSP System and lunar industry could provide materials and beamed energythroughout cis-lunar space and beyond. Design studies can explore the evolution of spacetravel and space habitation in the context of an energy–, materials–, and funding–rich two-planet economy.

LUNAR SOLAR POWER SYSTEM REFERENCE MODEL

TheTexas Space Grant Consortium will study how a Lunar Solar Power System with 20,000GWe capacity can be established by 2050. This LSP System Reference Model is a starting pointfor both detailed studies of the suggested components and operations and as a take-off point fordifferent approaches that make extensive use of lunar materials.

Figure 1 shows the general features of the LSP System Reference Model. The LSPSystem haspairs of solar power bases on opposite limbs of the moon, as seen from Earth. One base or theother receives dependable, direct sunlight over the full lunar day. Each solar power base containssolar photovoltaic arrays that output electric power. The power is converted to thousands ofbeams of microwave power. The beams are directed to collectors on Earth called rectennas. Thephotovoltaic arrays of each base are split between those on the Earthward side of the moon and asupplementary set of photovoltaics across the limb of the moon. The farside and earthward basesare connected by power lines.

On Earth the rectennas convert the microwaves to electricity and send the electricity into localpower grids. The LSP System Reference Model will include microwave relay satellites in orbitabout Earth. The satellites redirect LSP beams to receivers on Earth that can not directly viewthe power bases. The redirectors may be passive reflectors or may be active retransmitters thatoutput several beams to rectennas on Earth. The intensity of each beam is controlled to provideload following power at its rectenna on Earth.


The beams pass through clouds, rain, and dust. There is no need for long-distance powertransmission lines or indeterminately large systems to store power. Approximately once a yearthe Earth will eclipse the power bases for no more than 3 hours. This predictable outage can beaccommodated by power storage of defined capacity on Earth and/or the moon.

In this discussion the beams are assumed to have an intensity just above the rectenna of about20% that of sunlight (~ 250 W/m2 ).A few hundred meters from the edgeof the rectenna the intensity will be1% or less of the central intensity.Farther from the rectenna the straypower of a 20,000 GWe system willdrop in intensity to that of the lightfrom a full moon.

The high quality net new energyinput to Earth via microwaves isfully off-set by reflecting back tospace, from the area of the rectenna,an equal quantity of low-qualitysolar energy (i.e., sunlight).

Rectennas are the major costelement of the LSP System.However, the rectennas on Earth aremuch smaller in area and mass thanterrestrial arrays of photovoltaics ormirrors of comparable energyoutput. Therefore far less labor isrequired to maintain rectennas.Rectennas will occupy as little as5% of the land-area per unit ofreceived energy that is now devotedto the production and distribution ofelectricity.

A rectenna can begin outputtingcommercial power after it reaches ~0.5 km diameter. Additional

construction can be paid for out of current revenue. One-square kilometer area of rectenna areacan have an average output of 180 MWe. This one-square kilometer of rectenna produces everyyear the electric energy equivalent to burning 3.3 million barrels of oil or 650,000 tons of coal.

An American consumes ~11 kWt of power to provide his goods and services. By 2050 these canbe provided by approximately 4 kWe of electric power. Assuming 1980’s level of technology anarea on the moon half the size of a football field could supply 4 kWe at Earth. By 2020 that area

Sunlight

Base 1

Base 2

Orb ital

redirector

Many microw ave b eams

Source ofPow er

One of many smallrectennas

Figure: Lunar Solar Power System Reference Model


can drop to 3.5 meters on a side due to higher efficiency technologies, denser packing of solarcells on the moon, and solar sails (light buckets) in orbit about the moon. The collector on Earthwould be 28 m2/person, ~ 5.3 m or 17 ft on a side. Only a few kilograms of thin-film solarcollectors, microwave components, and beam collectors on Earth can power the averageAmerican for life.

Figure 2 depicts one concept of a manned lunar base to demonstrate the production ofcomponents from local lunar materials. LSP’s fundamental unit is a power plot. A power plotconsists of: a microwave reflector - the upright screen; a field of solar cells - in front of thereflector; and a set of microwave transmitters - under the mound beyond the solar array. Themoon rotates to keep the same side facing Earth. Thus, the Earth stays in the sky just above thehorizon of the lunar power base. A LSP base is constructed incrementally through the addition ofthousands of small power plots. Each power plot is stand-alone.

One power plot can transmit only a tiny flow of power toward Earth. The plots must beintegrated electronically into a very large fully segmented phased array radar that projects multiplebeams toward Earth. Note the circular areas in Figure 1. Each circular area appears to be filledwith the up-right reflectors in Figure 2. Over 95% of the microwave power in a given beam willintersect the rectenna and be converted to electricity at over 90% efficiency.

Lunar dust can be used to make the solar collectors, microwave transmitters, and large antennason the moon. Relatively small mobil factories are taken from Earth to the moon. On the mooneach factory produces hundreds of times its own mass in components to form this Lunar SolarPower (LSP) System. TSGC teams will design and analyze the machines and systems to makeand maintain the LSP System components.

There are no “magic” resources or technologies in Figures 1 or 2. The Earth-moon system, themoon, and the major and minor lunar resources are extremely well understood. Well over $500million dollars has been spent on lunar research since the start of the Apollo flights to the moon in1969. Lunar research continues through remote ground-based and satellite missions by theUnited States, Japan, Europeans, and many others.


Any handful of lunar dust and rocks contains at least 20% silicon, 40% oxygen, and 10% metals(iron, aluminum, etc.). Lunar dust can be used directly as thermal, electrical, and radiationshields, converted into glass, fiberglass, and ceramics, and processed chemically into its chemicalelements. Solar cells, electric wiring, micro-circuitry components, and the reflector screens canbe made out of lunar materials.

Microwave ovens, cellular phones, microprocessors, phased array radars, long-base line radiotelescopes, and orbital radarmapping of the Earth provide thebasic technologies and operatingexperience associated with thebeaming of power.

The LSP System Reference Model isestimated to have an ultimatecapacity the order of 1,000,000GWe. LSP System power isindependent of the biosphere. TheLSP System can establish a newtwo-planet economy between theEarth and the moon and net newwealth for everyone on Earth.

Overview Reference

Criswell, D. R. (1996, April/May)Lunar-solar power system, IEEEPOTENTIALS, 4-7, Inst. Electricand Electronic Engineers, NewYork (and references therein).

Other references are provided in thefollowing descriptions of LSPSYSTEM PROJECTS for designstudies and graduate research.

Figure 2: Demonstration LSP Production Base


COMMERCIAL POWER FROM SPACE: LSP SYSTEM PROJECTS

1.0 COMMENTS TO FACULTY AND STUDENTS

1.1 Senior Level Design Courses

Each of the following suggested projects contain many very tough challenges. Usually the majorchallenge in any large program is to coordinate efforts between projects that are occuring at thesame time and also from an early project to a later project. Both considerations apply to theTSGC Flagship Program on Commercial Power from Space. Faculty and students are stronglyencouraged to work closely between related projects and also understand the overall system.

It will be a challenge for any one Senior Design Team to complete a given project in one or eventwo semesters. It is hoped that the results of each Senior Design Team project will contribute toone or more parallel and subsequent Design Teams. Thus, each Design Team should clearlydefine its particular project or subproject, its relations to the overall system goals, and clearly statetheir results and document their analyses, software, and other products so their results will beuseful to other teams.

1.2 Graduate, Post-graduate, and Professional Studies

Faculty should be sensitive to the degree of skill and the knowledge bases necessary for thevarious projects and subprojects. Many projects can quickly move to the graduate, post-graduate,and professional level. Consider these as possible graduate topics to be proposed under aseparate TSGC Research Fellowship program or to another agency.

1.3 Team Projects for the Operating LSP System Reference Model (discipline lead)

In all of the following design efforts develop physical and engineering metrics for the variousdevices, systems, machinery, human support, consumables, etc. that can be translated into scalesof operations and costs by other groups. Carefully consider and specify the requirements andinterfaces (ex. information, mass transfer, delivered power, materials, labor content, powerdensity and frequency of a power beam, etc.) that must be shared with between the various designefforts.

NOTICE:

The statement gives approval for use of the materials herein for educational purposes and researchpurposes by students, faculty, and others associated with the Texas Space Grant Consortium forthe Program on Commercial Power from Space. The materials may be copied to paper or disk forthe purposes of education and research. For the purposes of education and research the materialsmay be included in reports and studies in both digital and hardcopy forms. Please reference any ofthese materials so used. The author reserves the right to use the materials in books, proposals,


and similar applications. The author makes no claims on materials added by others to thisprogram description.

2.0 USER REQUIREMENTS

Do people need 2 kWe/person? Does the world population really need an external source of netenergy that may be especially clean? Will the development of the moon as an industrial center beof benefit to individuals, companies, universities, nations, the world? The first consideration inany large program is the human needs and benefits. These can not be assumed. Given a need for2 kWe/person can the world organize the resources to construct such a system? This sectionfocuses on identifying the needs and requirements of the users and invites study of how toorganize the resources.

2.1 Human/Terrestrial Implications of Using Solar-Electric Power from Space/Moon:

2.1.1

Explore the economic, environmental, political and other implications of a terrestrial economythat is provided by 2050 with 20,000 GWe of electric power.

2.1.2

Review the historical and modern day roles of commerical energy (firewood, fossil and nuclear,etc.) in human society, industry, commerce, level of end-use technology, national and internationalpolitics, and other aspects. Consider the qualitative changes enabled by going from laborintensive biomass (ex. deforestation of England in the 1600s), to coal and oil (ex. economic riseand fall of the Texas and Saudi oil economies in the 1980s), the potential for internationalrestrictions on CO2 emissions (early 21st century), to adoption of LSP power that introduces netnew energy to the biosphere.

2.1.3

Study the introduction of electric power into various countries. Consider the history of electricityin US, Switzerland (early hydro), and other OECD countries. Compare this to the present dayapplication of electricity in developing countries. How does electricity use influence health,quality of life, longevity, economic growth, etc?

2.1.4

Specifically compare a carbon-limited economy to a world wide electric economy in which thereis no need to place restrictions on the use of carbon for fuels. Consider the conversion of coal,oil, and natural gas to a petrochemical market in the context of a potentially much richer worldeconomy.

2.1.5


Review the transition of energy use to goods and services from a thermal base (gas lighting,gasoline automobile, belt and pully power distribution in early factories, etc.) to an electric basis(electric lights and automobiles, electric wires and motors, electric communications, etc.). Whatare the qualitative and quantitative changes in costs of goods and services delivered, range ofgoods and services, safety, rapidity of change, and others?

2.1.6

What are the emerging technologies that can maintain the transition of the national and worldeconomices from a thermal to an electric base? What fundamental changes can be enabled by newelectric systems in industry, commerce, travel, residential services, health, safety, the decay rate ofwealth (human resources, natural resources, constructed resources), and other topics?

2.2. World Wealth and the Large Power Systems

2.2.1

Model the full costs of conventional power systems (biomass, coal, oil, natural gas, nuclear(termal and fast breeder reactors)) and terrestrial renewable power systems operated at the 60,000GWt (or 20,000 GWe) level by 2050 and maintained until 2100. Include effects of pollutions,loss of human life in supporting and using the systems, issues of proliferation of nuclear weapons,transition after depletion of major resources (ex. coal), uncertainty in supplies, and similar issues.

2.2.2

Explore the net world income as it depends on the total cost of energy over the 21st century.Consider historical data of a range of countries and attempt to extrapolate to 2100 for variouslevels of power usage and power cost. Consider studies by groups such as the World EnergyCouncil (Energy for tomorrow’s world, 1993), the U.S. Department of Energy, the NationalAcademy of Sciences (several reports on electricity and the national economy), and the OECD.

2.2.3

Contrast these questions to the short term approach, ~ 10 year horizon, taken by the U. S.Department of Energy in its various annual reports on energy planning.

2.3 The Environment and Large Scale Commercial Power

2.3.1

To what extent and at what cost can solar-electric power from space be used to decouple mosthuman activities from their present dependence on the biosphere. Examples of resourcesprovided by the biosphere are fresh rain water, biomass of alge and trees that supports long foodchaines,and recycling of human wastes (in streams cess-pools, and the ocean). Can widespread


electric power enable community-based or even home-scale units to recycle water and wastes andthereby greatly reduce the scale of water and sewer systems?

2.3.2

Consider the biosphere as a shell-shaped spacecraft where everyone lives on the outside and ask –to what extent power from space can be used by humans so that their activities have minimaleffects on the other occupants? Consider this question for a range of total human population overthe 21st century. Include the effects products that disperse (CO2, trace contaminates, etc.)throughout the biosphere and increase in concentration.

2.3.3

Examine the acquisition and recycling of non-renewable resources (demandite: metals, fertilizers,process chemicals, organic chemicals, etc.) though the use of electric power. How does cost ofnon-renewable materials vary versus the total cost of the primary electric energy ($/kWe-h)?

2.3.4

What physical, engineering, environmental, and physiological (human and non-human) factorsclearly limit the growth in the use of electric power and microwave power in a small area (home,farm, city block), a region (state or country), and on a world wide basis?

2.4 Commercial and Goverment Development

2.4.1

What are the potential economic benefits of implimenting the LSP System Reference Model?Who are the winners? Who are the losers? How much do they win and lose by and why? Howlarge is the LSP System Reference System in terms of costs and benefits compared to other majornational and international projects? Consider both government programs (ex. interstate highways,air traffic control, NASA, DoD high technology weapon systems, etc.) and commercial programs(ex. large international oil project, fleet of commerical satellites, etc.).

2.4.2

Review the political and legal basis for developing and implimenting the Reference System.Examine both national (U.S. and others) and international considerations. Note especially theestablished international treates on uses of outer space and treaties on analogous issues (ocean,environment, etc.). Consider the roles of governments in development of new, high risk ventures(Continental railways and waterways, communications satellites, interstate highways, etc.). Howdo these programs benefit governments? How do governments and private enterprise worktogether? Recommend several stratiges for government(s) envolvement in using the moon andimplimenting the LSP System Reference Model.

2.4.3


Identify the impediments for commercial organizations in starting and implimenting the LSPSystem Reference Model. What steps are necessary, and by whom, to overcome or side step theselimitations? Is it possible for the Reference System (lunar and rectenna portions) to become a“prudent investment” so that stocks can be issued and mutual funds can invest.

2.4.4

This is not a well formed sections. A design group with strengths in business, economics, law,international relations, government, engineering economics, etc. should develop this section.

A few starting references:

Ausubel, J. H. (1996, March/April), Can technology spare the Earth?, American Scientist, 84,166-177.

Baughman M., Barkovich B. R., and others (1986) Electricity in Economic Growth, 165pp.,National Academy Press, Washington, D.C.

Courtney J. C. and Lineberry M. J. (1992) Integral fast reactor (nuclear engineering), Encyclodeiaof Physical Science and Technology, 8, 163 - 172, Academic Press.

Criswell, D.R. (1995, 31 July-4 August). Lunar Solar Power System: System Options, Costs, andBenefits to Earth. Proceedings of the 30th Intersociety Energy Conversion EngineeringConference. (Orlando, FL). Paper #IECEC 95-23: Aerospace Power, Vol. 1, 595-600.

Criswell D. R. (1994, October) Net growth in the two-planet economy, 45th Congress Intern.Astronatuical Fed., IAF-94-IAA.8.1.704, 10pp., Jerusalem, Israel. (Available from: ISSO,Un. Houston, Houston, TX 77204-5505, 713-743-9135 / fax - 9134, and [email protected])

Criswell D. R. 1993 (7 July). Lunar Solar Power System and World Economic Development,10pp., Chapter 2.5.2 of Solar Energy and Space Report, in WORLD SOLAR SUMMIT,UNESCO. Paris (see UNESCO below).

Dept. of Energy (1995, July) Sustainable Energy Strategy (National Energy Plan), 73pp.,Superindendent of Doc., MS SSOP, Washington, D.C., 20402-9328, ISBN 0-16-048183-X.

Glaser, P. E., Davidson, F. P., and K. I. Csigi, K. I. (editors) (1993) SOLAR POWER SATELLITES: theemerging energy option, eds, pp.272-288. Ellis Horwood Limited., Chichester, England. (pluspublisher errors errata for pp. 272, 273, 284, 285. Major errors by Woodcook comparing He3,LSPS, and LSP in Tables 3 and 4, p. 269).

Goeller H.E. and Weinberg A.M. (1976) The age of substitutability, Science, Vol 191, 683-689.


Kennedy, P. (1993) Preparing for the 21st Century, 429 pp., Random House.

NASA (1989, July) Report of NASA Lunar Energy Enterprise Case Study Task Force, NASATech. Memorandum 101652, 178 pp, July

Schurr S. H., C. C. Burwell, W. D. Devine, Jr., and S. Sonenblum, Electricity in the AmericanEconomy, Electric Power Research Inst., 443, Greenwood Press, New York. (1990)

Stafford, T. P. (1991) America at the Threshold: America’s Space Exploration Initiative,Synthesis Group (T. P. Stafford - Chairman), 144pp. and 64pp appendix. U.S. GPO,Washington, D.C. 20402

Starr C. (1990) Implications of continuing electrification, 52-71, in Energy: Production,Consumption, and Consequences, National Academy Press, 296 pp., Wash. D.C.

UNESCO (1993, July) Solar Energy and Space Report, Chapter 2.5.2, in WORLD SOLAR SUMMIT,.Paris.Available – Attn: Dr. L. Deschamps, Director – Societe des Electriciens et desElectroniciens, 48 Rue de la Procession, Cedex 15 -75724 Paris, FRANCE

Waltz B. and Thompson R. G. (1995) International relative technical analysis of a U.S.commitment to Lunar Solar Power, AIP Conf. Proceedings 325, 1049-1054, Albq. NM,1995.

Weinberg, A. M. (1986, 9 May) Are breeder reactors still necessary?, Science, 232, 695 - 696.(This article is written after the serious nuclear accidents at Three Mile Island andChernobyl. Compare it to Weinberg (1977). Note the arguements concerning cost,reactor accident rates, and future needs for electricity).

Weinberg, A. M. (1977, September) To breed, or not to breed?, Across the Board: TheConference Board Magazine, XIV, #9, 4 - 23. (Very readable and thoughtful).

World Energy Council (1993) Energy for Tomorrow’s World, 320 pp., St. Martin’s Press.

2.2 Large Power Systems: Physical, Engineering, and Resources Fundamentals

Do the existence of the sun and fundamentals of physics and engineering force humankind towardaccessing solar energy in space for use on Earth? What are the fundamental considerations thatdetermine how efficient a power system can be in benefiting humanity?

2.2.1

Burning wood and uranium both produce heat that boils water into steam, the steam turns anelectric generator. Power output in both systems is proportional to the power density of the steamand the speed of sound in the steam. The generation and handling of high pressure steamintroduces certain common scaling relations into how much and what types of materials (steel,concrete, etc.) are required to output a given level of power. Jet turbines adapted from aircraft


have enabled natural gas to produce power at lower total costs than conventional coal and nuclearsteam systems. The stream flow in the very low mass jet engine operates at a higher powerdensity. Conversely, solar photons can produce electricity by simply being adsorbed in asubmicron thickness of silicon. Thus, given the sun, a small thin layer of silicon in space canoutput as much power as a huge turbine, furnance, and the wood that can be grown by a nation.

2.2.2

As another example, world wide growth of wood use is limited by photosynthesis. The utility ofuranium is controlled by the decision to use thermal reactors or fast breeder reactors. Wind andterrestrial solar are limited by their low power density and irregular availability. Develop atutorial on the fundamentals of large scale power systems that can support 20,000 GWe output.Detail the key resources, physical processes, the fundamental engineering limitations, powerstorage, labor required to support and maintain the system, damage to the environment andpeople, the handling of wastes, system life-time, etc.

A few starting references, references therein, and references in section 1.0:

Criswell, D.R. and Thompson, R.G. 1996. Data Envelopment Analysis of Space andTerrestrially–Based Large Scale Commercial Power Systems for Earth: A PrototypeAnalysis of Their Relative Economic Advantages, J. of Solar Energy, Special issue onPower from Space (Ed. P. Glaser), Vol. 56, #1, 119-131. Elsevier Science Ltd.,Pergamon.

Criswell D. R. and Waldron R. D (1993a) Results of analysis of a lunar-based power system toprovide Earth with 20,000 GW of electric power. A Global Warming Forum, R. A. Geyer(Ed.), pp.111-124, CRC Press and in Proc. SPS’91 Power from Space: 2nd Int. Symp.,Paris (1991b).

Criswell D.R. and Waldron R.D. (1990) Lunar system to supply solar electric power to Earth,Proc. 25th Intersociety Energy Conversion Engineering Conf., Vol. 1, p. 62 - 71,#900279, Amer. Inst. Chemical Engineering, Reno, NV.

G. Foley G. (1987). The Energy Question, 304 pp., Penguin Books Ltd.

Strickland J.K. (1996, January) Advantages of solar power satellites for base load electricalsupply compared to ground solar power, Solar Energy, 56, 1, p. 23-40, Pergamon.

World Energy Council (1993) Energy for Tomorrow’s World, 320 pp., St. Martin’s Press.(excellent reference).

3.0 HEALTH AND SAFETY OF BEAMED POWER

Health and safety are of paramont and increasing concern to people in all nations. The averagelife expectancy of humans, world wide, has increased dramatically over the 20th century. Thestandard of living is increasing. Any new power system must be safe and contribute to the


growing health of individuals everywhere. The LSP System Reference Model uses microwaves asthe means of deliverying power to Earth. There are concerns about this method of powerdelivery. It is necessary to consider all aspects of the health and safety of using microwaves as themajor method of deliverying power to Earth. The LSP can not be considered in isolation butmust be compared to other options for providing large scale power.

3.1 The Micowave Environment

3.1.1

Review the literature on the presence of microwaves in the biosphere. Include manmadeenvironment (radio, TV, cellular phones, ham radio operators using hand held transceivers,microwave ovens, telephone microwave relays, communication satellites, computers, 100 Wattlight bulb, etc.). Examine the natural microwave environment (lightening, blackbody radiation ofpeople and things, solar and cosmic background, etc.) microwave background. Extrapolate theliterature to other situations that have not been reported.

3.1.2 Conduct surveys of the microwave background within your environment.

3.2 Microwave Safety and Risks

3.2.1

Review the literature on microwave safety (industry and government standards, experiments, etc.)for the general population, industrial workers, military personnel, and animals. Consider themedical use of microwaves in diathermy and magnet resonance imaging. Review the means bywhich coherent and incoherent microwaves interact with humans and animals. Focus on thedifferencies between short term and continuous exposure to microwaves.

3.2.2

Consider recent law suits regarding cellular phones, ground stations for communications satellites,and radio frequency interference, and any other relevant cases or controverses. Project futurelegal risks.

3.3 Rectenna Siting and Beam Criteria

3.3.1

Review the NASA and DoE literature recommending the use of microwave power beamsoperating at 2.45 GHz and approximately 230 Watts/m2. Comment on and revise theserecommendations in view of the above reviews. Keep in mind that the 1970s NASA Solar PowerSatellite Reference System used a power beam that operated in the far field. LSP is proposed tooperate in the near field. Near field operation can significantly reduce the levels of microwave


outside the primary beam compared to a beam operated in the far field. However, microwaves arescattered weakly by the ionosphere. Rectennas reradiate a portion of the microwaves theyreceive. This is design and technology-level dependent. Also keep in mind that the NASA SPSprogram only considered 300 GWe of power from space. The LSP Reference System is projectedto 20,000 GWe and higher.

3.3.2

Identify known key health and safety issues. Suggest processes by which accurate knowledge ofknown and emerging healthy and safety issues can be continuously upgraded with minimum dely.

3.3.3

Provide, if reasonable, options for beam reception at various locations: near urban areas, nearlife-rich areas, within industrially zoned areas, remote regions (ex. deserts), extremely remoteregions (arctic, ocean sites) with low density of life.

3.4 Safety of Alternative Systems

3.4.1

Compare microwave effects to those of other power systems (nuclear, coal, biomass, solarterrestrial, etc.). Consider such questions as these. Can people live without nuclear emission?What are the full range of contaminates from burning coal? Are human pathogens released intothe human environment by the destruction of forests for fuel and agricultural lands?. How can theeffects of qualitatively different hazards be compared?

3.4.2

Weight the safety of beamed power against the known and projected hazards of existing andproposed large scale power systems and the style of life the various systems enable. Consider therisks of living in a polluted and energy starved world versus living in an energy rich world.Consider the ongoing work of the United Nations to decrease the world wide emissions of greenhouse gases by the buring of fossil fuels.

A few starting references:

IEEE C95.1–1991 (1994)., IEEE Standard for Safety Levels with Respect to Human Exposure toRadio Frequency Electromagnetic Fields, 3 kHz to 300 GHz. IEEE Service Center, 445Hoes Lane, Box 1331, Piscataway, NJ 08855-1331.

NRC (1981) Electric Power from Orbit: A Critique of a Satellite Solar Power System, 332 pp.,National Research Council, National Academy Press, Wash., D.C.


Polk C. and Postow E. (editors) (1991 5th printing) Handbook of Biological Effects ofElectromagnetic Fields, 503pp., CRC Press, Boca Raton.

4.0 LSP SYSTEM REFERENCE MODEL: OPERATING SYSTEM

4.1 System Overview

4.1.1

Create a systematic end-to-end systems performance analysis of the LSP System Reference Modelfor the conversion of sunlight to output electricity at Earth. Include conversion efficiencies (ex.sunlight to electric, electric to microwaves), operating times (duration of lunar day, periodrectenna can view moon, lunar eclipse duration), beam efficiency (fraction of power segmentedarray places in a main power beam), and all other factors that affect overall and instant to instantefficiency. Table 4.1.1 provides two examples. See Criswell 1995, October) and other referencesbelow.


4.1.2 The System Overviewmodel should accommodatechanges to the LSP SystemReference Model so designgroups can analyze suchsituations as transmitting toEarth only when a rectenna canview the Moon and includingpower storage. Enable themodel to accommodateseasonal and hemisphericchanges in local and globalpower consumption.

4.1.3

Make the data structure of themodel open and accessible toall design groups. Use themodel to define thenomenclature (names and IDcodes) of the variouscomponents, subsystems,systems, and operating states.

Bock E., 1979, LunarResources Utilizationfor Space Construction,Contract NAS9-15560,DRL Number T-1451,General Dynamics -

Convair Division, San Diego, CAa. Final Presentation (21 February 1979), Line Item 3, DRD Number DM253T, ID# 21029135,

171 pp.b. Final Report (30 April 1979) Volume II, Study Results, DRD No. MA-677T, Line Item 4,

eight chapters, approximately 500 pp: 1979.

Criswell D. R. (1995, October). Lunar Solar Power System: Scale and Cost versus TechnologyLevel, Boot-strapping, and Cost of Earth-to-orbit Transport, IAA-95-R.2.02, Oslo,Norway, 10 pp. (available from ISSO, Un.Houston, Houston, TX, 77204-5505, 713-743-9135 / fax -9134, [email protected])

Criswell, D. R. and Waldron, R. D. (1990, August). Lunar System to Supply Solar Electric Powerto Earth. Proceedings of the 25th Intersociety Energy Conversion Engineering

Parameter Symbol Baseline Advanced(All with LO mirrors and EO redirectors) 1980s >2000sSCALE FACTORSTotal rectenna output at Earth (GWe) Po 20,000 20,000Construction time (yr) Tc 30 30Equipment work hours per 24 hours Tw 23 23Number of power bases (pairs) Npb 12 12Beam intensity at rectenna center (mW/cm2) Fb 23 23Beam wavelength (cm) Lb 10 10Beam diffraction diameter at Earth (km) Bd 0.2 0.2ENERGY CONVERSION PARAMETERSSunlight to Solar Cell OutputSolar power in free space (W/m2) Psun 1,370 1,370Illumination of one cell (geometry) Ng 0.32 0.32LO mirrors (none = 1, full illum. = Pi) Nm 3.14 3.14Fill factor (cell ground area/base area) Nf 0.20 1.00Solar cell efficiency Nsc 0.1 0.35

Ng*Nm*Nf*Nsc*Ntl/Npv= E1 0.64% 35.00%S. Cell to Rectenna OutputElectric power collection effic. (I2R) Npc 0.94 0.99DC power conditioning (short storage) Npcm 0.96 0.99Electric to microwave conver. eff.(tubes) Nmw 0.85 0.95Lunar reflector efficiency Nsr 0.98 0.99Fraction of power into one beam Nbf 0.80 0.90Fraction of one beam toward rectenna Nb 0.95 0.95Reflector (satellite) efficiency Nsat 0.98 0.98Earth atmospheric transmission Na 0.98 0.98Antenna efficiency Nrec 0.89 0.98Microwave power conditioning Npce 0.88 0.98Electric grid connection effic. Ng 0.97 0.98Average system availability Navail 0.95 0.99

Npc*Npcm*********Ng*Navail= E2 39.60% 70.53Areal Conver. Eff.(E1*E3 = ) E4 0.25% 24.68%Average electric output (W) at Earth per m2 of lunar base (Psun*E4 =) Pe 3.45 338.18Conversion eff./unit of active cells = E4/Nf 1.26% 24.68 Area Bases/Area Moon Ab 15.26% 0.16%

Table 4.1.1. Functional parameters for two LSP Systems


Conference, Vol.1 "Aerospace Space Power Systems." pp. 61-71. (Reno, NV). Paper#900279

Miller, R., 1979, Extraterrestrial Materials Processing and Construction of Large SpaceStructures, NASA Contract NAS 8-32935, NASA CR-161293, Space Systems Lab.,MIT, 3 volumes.

These starting references are applicable to most of the following sections, especially 4.3.

4.2 System Visualization Model(s)

4.2.1

Create an accurately scaled, animated computer simulation of the operational 20,000 GWe LSPSystem Reference Model. Include the correct solar illumination, reasonably accuratecomputerized map of the moon, two or more pairs of lunar bases, resolvable power plots, cross-limb power bases, cross-limb transmission lines, visualizable power beams, power relay satellitesin orbit about Earth, reasonable accurate computerized map of the Earth, thousands of rectennaslocated near areas needing power, and simulated industrial and commercial power users(factories, cities, etc.). Consider making the model(s) object oriented so that different constructs(power plots, relay satellites, LEO and EO space stations, etc) can be entered by the variousdesign groups.

4.2.2

In more advanced projects allow the various installations on the moon, in space, and on Earth toscale in response to the key engineering parameters chacteristic of component technologies in1980, 2000, 2020, and 2050. Show the installation process of a power plot and an entire basesuperposed on actual lunar photography.

4.2.3

Use modeling tool(s) that permit the viewer to see the system from many different vantage pointsand lets users create fly-through animations off-line. Specify the data requirements other designgroups must meet to input their designs into the model.

4.3 Cost Modeling Tool (Software)

4.3.1

Adapt and/or develop a cost model of all major aspects of a LSP System (R&D, deployment tospace, demonstration, large scale implimentation, operations and maintenance of the space andlunar portions) and of the rectennas on Earth.

4.3.2


Minimize the number of input cost assumptions. For example, do not simply assume the cost ofproducing solar panels on the moon (ex. $/kWe peak). Rather, let internal costs such as this becalculated from more fundamental costs such as the costs on Earth of machinery manufactured onEarth and the costs on Earth of maintaining the transporation system.

4.3.3

Extend the model to the major subsystems level (production machinery, space vehicles, powerplot size and life time, etc.). Structure the data inputs to allow rapid consideration of varioustechnology options and evolution of the system. Include financial aspects (time value of money,effects of uncertainty, etc.). Make the model useful for archieving model results and availableover the web to all groups.

4.4 Solar Converters and Power Collection within Power Plots

4.4.1

There are many options for the converting solar power to electrical power and even directly tomicrowaves. Different means can be used in different power plots. Some solar conversionschemes allow storage of signficant energy for transmission for some time after sunset or duringthe ocassional eclipse of the moon by the Earth. Conceive and design one or more solarconversion schemes that take advantage of the lunar materials and environment. Take specialconcern with the extremes of temperature over the lunar day and the effects of solar and galacticcosmic rays.

4.4.2

Include means, as necessary, of collecting the solar electric power and feeding it into microwavegenerators. Analyze the overall efficiency of the power systems (from solar to electric input tothe microwave generators).

4.4.3

Explicitly consider how the power converters will be manufactured, set in place, monitored,maintained, repaired, and eventually upgraded as technology progresses. Explicitly consider theeffects of the size of the power plot. Specify the requirements that other Design Groups mustmeet to design the machinery that manufactures, implaces and maintains the solar collectors.

4.5 Microwave Generators, Plot Phasing, and Plot Optics

4.5.1

There are conventional (magnetrons, MMIC, etc.) and unconventional methods for changingelectric power into microwaves that can be precisely controlled in phase and amplitude


distribution. Survey the possibilities and select one or more methods for analysis. Focus onmethods that make maximum effective use of the lunar environment and materials, provide longand stable operation, and can be made largely or completely on the moon. Consider the evolutionof phased array radars on Earth from central generators, wave guids, and phase shifters tomonolithic microwave integrated circuits, etc. and newer approaches.

4.5.2

It is likely that the microwaves will be directed toward a subaparture(s), a large reflector(s) orlens, and then toward Earth. Explore several subaparture geometries and devices that can bemade efficiently from lunar materials. It may be necessary for the subapertures to move slowly totrack the Earth. Explore electronic, geometric, and/or mechanical means of tracking Earth.

4.5.3

The objective is to have each plot emit many separately controllable subbeams. Consider thecomputer control necessary to phase multiple beams and the means of establishing the necessaryabsolute and/or relative time base for control of subbeams.

4.6 Fully Segmented Microwave Arrays, Optics and Phasing

4.6.1

Each fully segmented transmitting array on the moon is planned to be operated as a multi-beamsystem. Each beam is to be operated so that the Earth is well within the near field of the array.Thus, each beam can be formed, focused on its rectenna (or orbital redirector satellite), track therectenna, and then be unformed when the rectenna moves out of the effective field of view. Writean overview paper of the beaming process. Identify critical technical and operational issues.

4.6.2

Review the literature of phased array transmitters and receivers. Consider the new large solidstate radar units, consider the Very Large Array radio telescope in New Mexico (a receiver), theGlobal Positioning System, and other working and proposed distributed arrays. Write a paperdetailing the lessons learned in these operational systems that are applicable to the LSP SystemReference System.

4.6.3

Understand the physics and electrical engineering of a near field, fully segmented phased array.Adapt that knowledge to phasing the lunar multi-beam arrays. Consider the use of referencesignals and absolute time bases. Review the evolution of absolute clocks and their industrial andresearch applications. Quantify the advantages and disadvantages of the lunar environment, themoon as a plateform for beaming power to Earth and Earth orbiting satellites. Write a softwarepackage to model the beaming by a fully segmented phased array (multibeam) system.


4.6.4

Investigate the effects of the plasma environments about the moon, cis-lunar space, and theionosphere on the structure of the power beams.

4.6.5

Consider the effects of the power beam on the ionosphere and atmosphere of Earth and vis versa(disrupting the phase, scattering of microwaves out of the beam, adsorption in rain, effects offog).

4.6.6

Propose one or more methods of phasing and controlling the amplitude of a multi-beam, fullysegmented phased array.

4.6.7

Consider and propose methods to safe guard against the creation of high intensity beams thatcould create safety hazards in space, the atmosphere, or on Earth. Where ever possible proposephysical and engineering embodiments that can be built into the arrays so as to precludeundesirable power levels (ex. limit the array diameter for a given wave length of microwaves).Consider the generation of radio frequence interference (RFI), predict the expected levels (versuspower, beams, variation in beam sweep rates in space, frequency, and amplitude), discuss theimpacts of the RFI. Suggest how commercial products can be shielded against RFI.

4.6.8

Suggest and analyze means for early demonstrations of the phasing of sparce arrays on the moon.Refer to the DEOMONSTRATIONS section.

4.7 Redirector Satellites

The scale and cost of the LSP System Reference Model is significantly decreased if power can bedelivered to each rectenna when it is needed. This is referred to as “load following” in the powerindustry. This is far less expensive than transmitting excess power to a rectenna when it can viewthe moon, storing the excess energy for up to 18 hours, and releasing the energy when the moonis not in view. This is the same problem faced by using solar energy on Earth. Except, LSP candependably deliver power through rain and clouds and the microwaves are converted to electrictywith high efficiency. Storage can be avoided by sending a power beam from the LSP base to asatellite that redirects the beam to rectenna on Earth. The redirector satellite should maintain thebeam to Earth in a near field condition. Treat the satellite design from the fleet and single satelliteview points.

4.7.1


Model and design reflector satellites. There will be approximately one reflector satellite for eachbeam and rectenna on Earth. Consider the precision required in pointing, surface accuracy, andslewing. Remember the moon-to-satellite beam might be jiggered to take out some mechanicalpointing inaccuracies. How can the satellite be slewed and stablized with minimum use ofreaction mass? What orbits can be used? Consider a wide range of orbital options. Whatproblems and limitations will arise for the fleet from orbital debris? Consider deploying thereflector from LEO and from LLO.

4.7.2

Model and design retransmitter satellites. Design a retransmitter satellite that accepts beamedmicrowaves, perhaps even laser power, from the moon. The lunar beam might be delivered atconsiderably greater than 200 Watts/m2 and at frequencies that can not pass through theatmosphere of Earth. The retransmitter satellite then converts that power to multiple beams thatare each separately redirected to rectennas on Earth. Explore the retransmission of power at thesame and different frequencies from that of the lunar beam. Consider the satellite and fleetproblems described in the above section on reflector satellites.

4.7.3

Related Technologies. Review and consider radio astronomy systems that actively map the moonand asteroids, review the Shuttle Mapping Radar, and possibly military mappers, and thereception in deep space of high powered microwave signal from Earth for insights in to operatingredirector satellites and beaming power from space to the moon. Can reciproscity be utilized tounderstand the beaming of power to Earth?

4.7.4

Compare redirector satellites to various Solar Power Satellite System options where both fleetsoperate at the 20,000 GWe level and higher. Consider debris, orbital control, collision avoidance,reaction mass introduced into the magnetosphere, visual and RFI signals at Earth, effects onsafety of spaceships and other orbital facilities, maintenance of the respective fleets, and othertopics that come to mind.

4.7.5

Orbtial Debris: Consider the possibility that the breakup of a fleet of Space Solar Power Satellitesor redirector satellites could make travel from Earth to deep space extremely hazardous.Generate a model of the debris hazard versus system power level.

4.8 Rectennas

Efficient rectennas were designed and demonstrated in the 1970s during the NASA/DoE studiesof power from space. The antennas and diodes were relatively heavy and were supported byrelatively massive structures of aluminum and cement, like terrestrial solar arrays. Todayefficiency rectennas can be produced as very light weight printed circuitry on strong plastics


sheets and webs. Some of these designs have been used as the surface covering of small aircraft.The aircraft have flown using electric motors powered by microwaves transmitted to them fromthe ground. Researchers in Russia, the Ukraine and elsewhere have designed klystrons andmagentrons that run backwards. Microwaves are focused into them and electricity is output.Advances in high temperature superconductors may enable enable rectennas that operate over anespecially wide range of frequencies and aspect angle.

4.8.1

Review the physics, engineering, and technology of rectennas. Identify the key physical aspects ofmicrowave-to-electricity conversion that establish minimum intensity levels for the beam andminimum phase coherence of the beam.

4.8.2

Estimate the costs of producing and installing the various types of rectennas. Compare thesecosts to conventional systems to generate power. Consider different types of rectennas thatoperate a different beam power density, frequency, polarization, and even with multiple beaminputs.

4.8.3

Explicitly investiage efficiency of conversion of microwaves to electricity and the reradiation ofuncaptured or stimulated microwaves. Consider means to attenuate the reradiated microwaves.Consider the design of rectenna systems that can be repaired while the rectenna is in operation.

4.8.4

Consider the health and safety of workers who repair and maintain the rectennas. Will specialsuits be required, as in fire fighting. Will extensive use be made of robots that operateautomatically and extract their power from the rectenna. Design rectennas that are robot friendlyfor rectennas installation, mainteance, repair, and replacement.

4.8.5

Examine siting of the rectennas. Consider the relation of rectenna diameter, wave length, powerdensity of the beam, and profile of stray microwaves to locating potential sites for rectennas.Trade off minimum rectenna diameter versus minimum apparent diameter of the lunar powerbases and the redirector satellites.

4.8.6

Consider the appeal to the local population of voting on how to trade off power beam intensity tothe cost of energy. Energy will increase in cost as the intensity of the beam decreases.

4.8.7


Consider the integration of rectennas over industrial complexes such as aluminum refining orNaCl electrorefining, large manufacturing centers, and complexes to produce synthetic fuels suchas hydrogen, recycle wastes, and purify and desalt water. Consider integrating rectennas andcommercially zoned areas (warehousing and transportation nodes, air ports, etc.).

4.8.8

Compare the energy output of rectennas to conventional power systems and terrestrial renewablesystems. Note factors such as fuel use, land area use, noise, pollution, and other physical,environmental, political, and financial issues.

4.8.9

Analyze the economic benefits of introducing inexpensive electricity into an area (TVA and GrandCoulee in the 1940s and 50s). Use these examples to project the pay-offs to areas of thedeveloping countries (China, India, sub-Sahara Afric, etc.) to receiving a rectenna. Explorewhether or not local production and installation of rectennas could jump-start the technicaleconomy of developing countries?

4.9 Providing Power Storage during Lunar Eclipse

Approximately once a year the moon is fully eclipsed by the Earth. Full lunar darkness lasts up to3 hours. There are two options. Power storage (~ 20,000 GWe-hr) is provided on the moon, inspace, or on Earth. Also, a fleet of solar sails in orbit about the moon, but outside the full shadowcone of the Earth, could be used to reflect power to several or all of the power stations. The sailsdo not necessarily have to be high precision mirrors capable of imaging the sun on the powerplots. Rather, they simply have to reflect photons over major portions of a power plot. Sails canalso send solar power to the moon during regular operations. This tends to decrease the size andcomplexity of the power stations. Use of solar sails may affect the design of solar arrays on themoon.

4.9.1

Global Power Storage Needs: Analyze the power storage needs and options (moon, space, Earth,combinations there of) so that the LSP System can provide power on Earth during eclipses of themoon. Consider the possibity that an electric economy in 2050 will have sufficient storagecapacity in batteries, synthetic fuels/generators, electric automobiles, home storage units, etc. thatsuch sort term and defined storage will not be a problem.

4.9.2

Lunar Active Storage: Examine solar-to-electric conversion methods on the moon thatintrinsically store power for 3 hours or more. These include, but are not limited to, use of moltenor heated lunar soil to drive a heat engine or the use of heated cavities that drivethermophotovoltaics Such schemes will likely require more site preparation and materials


processing than associated with thin film photovoltaics. Work with other design groups toevaluate the affects of these more massive solar-to-electric conversion schemes on the overallproducibility of the LSP System Reference Model.

4.9.3

Lunar Power Storage Needs: Consider the power needs during the eclipse period of the variousinstallations on the moon and in space that support the LSP System Reference Model. Analyzethe influence and availability of power storage on the overall reliability of the distributed LSPSystem.

4.9.4

Fleet of Lunar Orbiting Solar Sails: Design a fleet of solar sails, made predominately from lunarmaterials, that can reflect sunlight to the power bases during an eclipse of the moon by the Earth.Design means to control the attitude so they can be pointed to reflect sunlight to the power bases.

4.9.5

Create a computer model of the fleet of sails in orbit about the moon and investigate wherether ornot the sails can be controlled sufficiently to avoid collisions and maintain acceptable orbits aboutthe moon. Work with other design groups to relate the characteristics of the fleet to the overallend-to-end efficiency of the conversion of sunlight-to-busbar electric output at Earth. The higherthis efficiency the lower total area of solar sails needed in lunar orbit.

4.10 LSP System without EO Redirectors and with Massive Power Storage on Earth

The LSP System can be “simplified” to bases only on the Earthward side of the moon and inwhich the Lunar Power Bases beam energy only to rectennas on Earth while the rectennas canview the moon. This requires massive cycling of power in and out of storage units on Earth.Previous analyzes indicate that this power storage will be more expensive than the LSP bases onthe moon and the rectennas on Earth. However, the LSP power storage can be less expensivethan terrestrial renewable power systems with sufficient power storage to provide reliable output.The LSP power storage will likely be competitive with fossil or nuclear power systems.

4.10.1

Model power storage required on Earth for a 20,000 GWe output system. Consider the casewhere rectennas receive power only when the moon is 30 degrees or higher in the sky above eachrectenna. Work with other design groups to understand how massive power storage on Earthaffects the cost of the lunar bases and rectennas. Include the distribution of power to usersaround the globe. Explore several different types of power storage (ex. surface hydro, deeppumped hydro, generation of hydrogen and its reuse in turbines, etc.).


Criswell, D.R. (1995, 31 July-4 August). Lunar Solar Power System: System Options, Costs, andBenefits to Earth. Proceedings of the 30th Intersociety Energy Conversion EngineeringConference. (Orlando, FL). Paper #IECEC 95-23: Aerospace Power, Vol. 1, 595-600.

4.10.2

Develop life cycle cost models of the various power storage options.

4.10.3

Explore and detail the environmental, health and safety, economic, and other issues associatedwith massive storage of power to support the “simplified” LSP System Model.

4.10.4

Explore synergisms between the massive LSP power storage system and terrestrial renewablessuch as solar, wind, and hydroelectricity. Can a hybrid system offer cost savings over using thevarious terrestrial renewable systems as stand-alone sources of power?

4.10.5

Explore synergisms between the massive LSP power storage system and terrestrial non-renewablepower systems (fossil, fission). At what cost can the LSP stored energy serve as a “fuel” saver?

4.11 Reliability of the LSP System Reference Model

The LSP Systems will be distributed and highly redundant. It is composed of many stand-alonepower plots and many rectennas. A given power base can form accurate beams even when asignificant fraction of the power plots are not operating. Many different types of powerconversions schemes can be used at the thousand of power plots. Many different types ofrectennas can be deployed on Earth and in space. Thus, the LSP System can be repaired andupgraded while it is in operation, somewhat like upgrading individual nodal computers while theinternet is operating.

4.11.1

Explore and identify what factors control the reliabililty of the LSP System Reference Model as amajor source of power for Earth. Consider all aspects of the operating systems. Examine naturaleffects such as moonquakes, meteor impacts, solar flares, changes in solar output (visible, UV, x-ray), motion of lunar dust, variations in the solar wind plasma and the ionosphere, and othereffects. Consider natural conditions on Earth such as earthquakes, volcanic plumbs, heavy rainand flooding, to name only a few. Consider engineering factors such as maintaining the phasingof the microwave transmitters in the power plots, the possible ways military or terrorist attackscould affect the system.

4.11.2


Consider economic and political senarios. Make reference to historical and academic studies ofpresent (coal, oil, biomass) and proposed (breeder reactors) power systems. Carefully considerthe responses of humans, including the members of your study and yourself, to fear of newsystems, fear of microwaves and electricity, major expansion of human travel beyond Earth,concerns of “who controls the moon” and thus controls the flow of power to Earth, and similarfactors that represent fundamentally new paths for people and humanity. Consider corporate andnational competition and cooperation as major factors.

4.11.3

Identify “show stoppers” and other critical issues that would influence decisions to impliment theReference Model or any other approach for a LSP System. Question whether 2 kWe/person isreally needed. Perhaps poverty of physical and biospheric resources are acceptable or evendesired by the majority of humans.

4.11.4

Develop the requirements for the outputs and data inputs to direct the construction of a softwaremodel of the reliability of the LSP System Reference Model.

4.11.5

Construct, to some level of utility, a reliability model that can be used by other design groups toevaluate their engineering designs and systems studies.

4.11.6

Continue to evolve, refine, and rebuild the reliability model(s) and apply to all aspects of the LSPSystem development and implimentation.

5.0 CONSTRUCTION OF THE LSP SYSTEM REFERENCE MODEL

Given the Moon the next key to the LSP System is the efficient construction of most, if not all,components from lunar materials. Transporting machinery and people to the moon is extremelyexpensive now and will likely remain expensive during the early phases of the LSP program. It isnecessary to gain high leverage from every ton of machinery sent to the moon. High leverage isgained by sending machines of production to the moon that will output at least hundreds of timestheir own mass in the form of installed power components that are made from lunar materials.Efficient production comes from several interrelating factors:

• Designing LSP components for efficient construction and implacement on the moon.• Designing LSP components for efficient, long life operation on the moon, and maximum life-

time output of energy.


• Machines of production that efficiently produce, implace, and repair the lunar derivedcomponents

• Minimizing the cost of importing from Earth LSP components and supplies, machines ofproduction, and people.

• Continually iterating the above factors so that multiplicative learning can continually occur asthe LSP System Reference Model is constructed and the efficiency of production cancontinually increase.

This section focuses on designing the machines and support systems that will be deployed fromEarth to the Moon and to Lunar orbit to construct the LSP System Reference Model. It includesthe defintion of operating procedures to conduct the implacement operations. Design Studies andgraduate studies in this section are intimently related to those of section 4, especially the tasksassociated with the design of LSP components and the trades between local lunar production andimport from Earth. Creative thought directed to sections 4 and 5 will very likely result in betterdesigns and methods of implimenting the LSP System.

Some potentially useful references on the moon and processing of lunar materials are given below.Refer also to references to Bock, Miller, and others in the earlier sections.

Criswell D. R. and Waldron R.D., 1979, "Extraterrestrial Materials Processing & andConstruction," available on microfiche, National Technical Information Service, 450pp.

Criswell D. R., Waldron R. D., Erstfeld T., 1980, "Extraterrestrial Materials Processing & andConstruction," available on microfiche, National Technical Information Service, 500pp.

Criswell, D. R. and D. R. Waldron. 1982. Lunar Utilization. In CRC Handbook on SpaceIndustrialization., ed B. O'Leary. 2: 1-53. Boca Raton, FL.

Heiken, G. H., Vaninman D. T., and French B. M. (1991) LUNAR SOURCEBOOK: A User’sGuide to the Moon, 736pp, Cambridge University Press, NY.

NASA Reports and Summer Studies

Space Resources and Space Settlements (1979) J. Billingham, W. Gilbreath, and B. O'Leary(editors), NASA SP-428.

Advanced Automation for Space Missions: Proc. 1980 NASA/ASEE Summer Study held at theUniv. Santa Clara, CA, ed. R. A. Freitas, Jr. and W. P. Gilbreath. 77-188. NASA CP-2255. Washington, D.C.: U.S. Govt. Printing Office. (especially useful for manufacturingstudies).

Lunar Bases and Space Activities of the 21st Century (1985) W. W. Mendell (editor), 860PP.,Lunar and Planetary Inst., Houston, TX, 77058.


Space Resources (1992) M. F. McKay, D. S. McKay, and M. B. Duke (editors), NASA SP-509,Overview and 4 volumns

Space’96 (‘94, ‘92, ‘90, etc). Proceedings of the Semi-annual meeting of the Engineering,Construction, and Operations in Space V (IV, III, II, and I), S W. Johnson (editor),American Society of Civil Engineers, Albq., NM, available ASCE, 345 East 47th St., NY,NY, 10017-2398.

Waldron, R. D. and D. R. Criswell. 1982. Processing of Lunar Materials. In CRC Handbook onSpace Industrialization, ed. B. O'Leary. 1: 94-130. Boca Raton, FL.

Waldron, R. D., T. E. Erstfeld, and D. R. Criswell (1979) The Role of Chemical Engineering inSpace Manufacturing. Chemical Engineering (12 February): 82-94.Translated into Chinese. 1979 American Industrial Report, (September) Issue No. 37: 26-43. (in #63.)

5.1 Power Plot(s)

The basic cell of the LSP System is the power plot. Refer to the general discription of the LSPSystem in the overview. One type of power plot can be replicated to form a power base.However, a given power beam from a power based is formed by integrating, in free space, themicrowave output of thousands of power plots. Thus, power plots can use many differentmethods to convert solar power to microwave power. There can be more than one type of powerplot and therefore more than one set of production equipment. The following discriptions ofproduction equipment are based on the plot components and production equipment shown inFigure 2 of the LSP overview at the start of this document.

The following steps assume lunar surveys are already completed of where bases and their plotswill be located. It is nominally assumed a plot will be approximately 100 meters on a side.However, there is no need to have all plots the same size. The only strict requirement is thatwhen the base is viewed from the Earth all the reflectors at the end of the plots appear to overlapinto one filled array.

The following section suggests projects to design several different machines and physcial/chemicalprocesses. Each design group should also specify the requirements, if needed, for experiments tobe done on Earth, the International Space Station, and the Moon to prove the correctness of theirproposed design. These can be input to the DEMONSTRATION section.

5.1.1

Using Apollo and/or Climentine data develop computerized maps that locate power plots in 8pairs of bases on the two limbs of the moon. Arrange the power plots so that when viewed fromEarth the microwave reflectors appear to overlap into monolithic apertures. Make the size of theplot reflectors variable to minimize siting problems. Make the array diameter variable. Be sure toallow for the libration of the moon.


5.1.2

In all of these design studies careful attention must be given to quantity of mass moved, the rateof mass processing, power source, power consumption, distance travel, nature of the processingsteps, methods of controlling the processes (automatically, monitor from Earth, etc.), repair andmaintenance of the equipment, and other factors special to the particular task. It is important totransition all the systems to using solar power (thermal and/or electric) as soon as possible.Develop a mass flow and mass processing model (software) that can be used by the systems andequipment groups to analyze their designs.

5.1.3

Grading and Gathering Soil and Power Plot Preparation: Design the mobile tractors needed tograde the plots, remove major rocks, collect size sorted soils for use in glass production, andpossibly lay down a system of buried electric wires for collection of the solar electric power.Designers of the power plots should strongly emphasize PV arrays and power collection designsthat minimize movement of lunar soil. The tractors may be used for more than one purposethrough the use of detachable devices. Avoid contamination of moving parts with lunar dust willbe one of the serious problems.

5.1.4

Beneficiation of Gathered Soil for Special Grain Fractions and Iron: Design several means ofseparating out soils on the basis of clarity, mineral concentration, and iron content are needed.Typical means of separating or beneficiating are magnetic, electrostatis, weight, size, and density.Should the beneficiation devices be incorporated with the mobil tractors or separate. There is alarge literature on beneficiation of terrestrial ores.

5.1.5

Production of Glasses, Ceramics, Basalts, and Iron: Lunar glasses, and possibly ceramics andbasalts, will be the major tonnage product of the lunar factories. The products include sheet glassfor supporting photovoltaics, columns and beams for reflectors, structural elements for stablefoundations and supports, and fiber glass for reflector screens and winding into fiberglassstructures. A major concern with lunar fiber glass is the need for a binding agent. Lunar iron oraluminum might be used. Consider both solar thermal and electric means of heating and meltinglunar soil (both bulk and beneficiated soils). All lunar soils contain approximately 0.1% by weightof mechanically free iron and some contain a larger percentage of pure iron grains (submicron)inside lunar glasses and minerals. Design melting processes that will recover the maximumfraction of the lunar iron without chemical processes and output this iron in the form of wire. Thewire will be used for elecrical connections, as input to power metallurgy manufacturing, for vapordeposition onto fiber glass to make reflective screens, and melted and formed into parts. Thereare several design projects in this section. They include the design of glasses based on lunarresources, the design of glass making machines, and the extraction of iron from glasses.

5.1.6


Solar Photovoltaics Emplacement and Wiring a Power Plot: Design tractors and or tractorattachments for the emplacement of solar arrays, wiring the array for collecting the solar electricpower, and connecting the array to the wiring system. In Figure 2 the PV arrays are shownsetting on the lunar soil. That may not be necessary. It might be better to hang them above thesurface, like clothes on a line, and rotate them over the course of a lunar day. Consider theinterrelations between PV design, implacement, service life-time, and maintenance and repair.Attention must be given to testing, on-site repair, and maintenance of the PVs. As with allactivities in a power plot the activity should not generate ballisti sprays of lunar or electrostatictransport of dust.

5.1.7

Emplacing the Microwave Power Units: The Reference Model assumes the microwave powerunits are buried under the lunar soil and transmit thourgh the strurctured mound of soil. The soilprotects electronics primarily from thermal changes over the course of the lunar day and fromsolar cosmic rays. Extremely radiation sensitive parts might be more deeply buried, over 3meters, to protect them from galactic cosmic rays. Burial makes heat rejection a tougherproblem. There will likely be heat rejection fins on the surface of the mound that must beconnected to the microwave power unit. On the other hand the microwaave units may besufficiently rugged that burial is not necessary. Design the emplacement process for theMicrowave Power Units. Work closely with the group that designs the micorwave power units.The units may actually be long in the east-west direction so that electronic phase control can beused to form the beams directed toward the large reflectors.

5. 1.8

Assembling and Emplacing the Microwave Reflectors (s): A well defined and confined beam atEarth requires a fully or nearly fully filled aperture. This is provided by the screens at the end ofeach power plot that are shown in Figure 2. There may be smaller screens at the opposite endthat form the subbeams as they leave the microwave power units. Work with the beam formingdesign groups in planning the tractors and special tools to install the reflectors. The reflectors willlikely require foundation structures and devices to slow move the primary reflector and/or thesecondary reflector over the course of the lunar month. The reflectors will likely require assemblyof the support structures, attachment of the reflective grid, possibly stalization structures acrossthe grid, and mounting of the reflector on the foundation points. On the other hand, perhapsdistributed transmitters are possibly, such as wire based microwave emitters, that can be mucheasier to put up and can be fully adjusted electronically.

5.1.9

Testing and Maintaining the Power Plots: Identify the needs for testing, maintenance, and repairof the power plot components. Design equipment, possibly based on the emplacement tractorsand tools, to conduct these tasks.

5.1.10


Transporter of Plot Emplacement System within a Power Base: The set of machines used toconstruct the thousands of power plots will somewhat resembly equipment sets used to constructhighways. Consider whether the primary devices are self mobile and can move from site-to-siteunder their own power or whether there is a need for a large “truck” to move some constructionequipment. There will very likely be a need for a long distance truck to transport brokenequipment back to a central repair facility or for a mobil repair facility that might have toaccommodate workers. There are several major NASAstudies of transporter sized vehicles. Themost extensive was done by Rockwell in the 1970s. Do a literature review to save some time.

5.2 Power Base(s)

5.2.1

Phasing and Communication Systems For the Power Base: There are several general methods ofphasing the thousands of mircrowave power units in a power base to generate the hundreds tothousands of power beams. The options are considered and defined by Design Groups 4.6.2 and4.6.3. For example, space systems such as a master clock at L1 or a GPS-like array in orbit aboutthe moon are possible. On the other hand there may be a need to user laser relays or emplacefiber optics phasing and communications networks between the power plots. Select the methodsof phasing and communications and design the emplacement equipment (perhaps only satellites)that will be used.

5.2.2

Production of Solar Photovoltaics (Earthward and Cross-limb bases): Design a facility tomanufacture thin film photovoltaics on the surface of lunar derived thin sheets of lunar glass.Review the literature on the options for various types of solar cells (silicon, gallium arsenide,etc.). Carefully consider the potential properties of glasses formed in a vacuum that have noexposure to water or hydrogen. The product should be easily transportable to distant power plotsor prehaps the production facility should be transportable. Plan a facility that does notcontaminate the local lunar environment and requires little if any make-up materials from Earth.

5.2.3

Manufacturing and Assemblying the Microwave Power Units: Design a manufacturing andassembly faciity for the microwave power units. If magnetrons are used this facility may bedominated by glass forming to make the chambers and metal operations for forming magnets andconductive layers. It is likely that solid state conversion devices are preferrable. The facility maymake simplier printed circuitry and import from Earth microwave circuity components that will beassemblied on the moon. Work closely with the groups designing the microwave power units.Consider the packaging and transport of power units to the power plots and the installationprocedures. Always work toward designs that make maximum use of the lunar environment andentail minimal handling of parts and assemblies. Carefully consider how to keep all power unitsclean. Review industrial work on cellular phones, modules for solid state radars, and similartechnology. Contact industrial experts for guidance.


5.2.4

Chemical Plant(s) for Producing Silanes, Silicon, Oxygen, Refined Iron, and Aluminum, andVolatiles Recovered from Glass Production

Lunar soils high concentrations of the major elements silicon, oxygen, calcium, iron, aluminum,and other useful elements depending on the location. Silicon is useful in forming silicon solarcells, specialty glasses, and microcircuitry. Silicon is the major element in silane. It is potentiallyuseful in production of silicon solar cells and as a fuel (SiH4, etc) for rockets or vehicles (closedloop). Oxygen is useful in life support, rockets, and oxygen/silane fuels. Aluminum and iron areuseful as electrical wiring, structural components, and many other functions.

Significant quantities of volatile elements and compounds will be released in the melting of lunarsoil to form glass. It is conceivable that volatiles will be released well in excess of those neededfor manufacturing, life-support, and transportation. If so explore and identify other possibleproducts for use on the moon, in space, or even back on Earth.

Review the literature on lunar resources and chemical processing of lunar materials. Work withthe design groups on components, manufacturing, operations, and transportation to determine themajor needs for refined materials. These needs will likely vary over the life-cycle of the LSPSystem Reference Model. The NASA Johnson Space Center has supported studies of lunaroxygen and water production.

Design one or more types of chemical, electrochemical, thermal, or combined plant(s) to provideone or more of the most useful elements and compounds. Consider only systems that willproduce far more product than the amounts of materials required from Earth to operate thesystem. Always work against your own project objectives and seek and suggest designs andmaterials that minimize the need for chemical processing, especially those that require importsfrom Earth.

5.2.5 Moon to Space Transportation Facilities and Craft.

The power base must accommodate the landing of large payloads and people. However, thetransporation operations must not destrub and certainly not degreade the power plots in the homebase or others. Review the literature on the various means of traveling between lunar orbit andthe surface. Design vehicles and lunar surface facilities that are scaled to accommodate theimport needs of the LSP System Reference Model. Consider the use of lunar materials tomaintain and refuel the vehicles Transportation needs will likely change over the life-cycle of theReference Model. Identify those changes and design systems to accommodate the changes ordesign a range of transportation options. Transporation requirements will be very sensitive toover all technology level and efficiency of the LSP System Reference Model, to the productivityof the emplacement systems, and to the use of lunar materials and resources.

5.2.6 Moon to Space Bulk Transport


If solar sails are used in lunar orbit to illuminate the power bases then a means is needed fortransporting large tonnage of selected lunar soil or fused soil. Consider several means ofdelivering lunar soil or fused billets to the LO Space Facility, deep space, or even back to orbitabout Earth. Lunar soil delivered inexpensively and safely to low orbit about Earth affordsseveral ways of drastically reducing the cost of space logistics. Focus on schemes that requirerelatively small and roboust machines. Transporation requirements will be very sensitive to overall technology level and efficiency of the LSP System Reference Model and the mass per unit areaof the Solar Sails.

5.2.7 Human Base: Habitats, Shops, and R&D Facilities

Carefully consider the functions that people must provide to construct, maintain, control, andevolve the LSP System Reference Model. Identify these functions. Use those functions toidentify the types and sizes of habitable facilities needed and their associated support systems(water, air, food, living, temperature, radiation protection, etc.). Draw on previous studies oflunar bases, the International Space Station, and long duration flights to Mars.

Very carefully consider use of people on Earth via teleoperation and telepresence to support allphases of the emplacement phase and operations. Consider how “Earthlings” can directly supportthe people at the power base. Estimate the size of the “Earthlings” labor pool, their skills andsalary levels, and suggest potential locations for commercial LSP Remote Control sites.

Identify high value R&D activities to be conducted at the power base that would accelerate theproductivity of emplacment systems and enhance the operations of the power base.

5.3 Cross-Limb Power Transmission

The LSP System Reference Model assumes that each power base consists of two photovoltaicarrays. One on the Earthward side of the Moon and the other just across the limb of the Moonfrom the Earth. Other groups will design long distance transmission lines (possibly high tensionlines elevated above the surface, possibly superconducing lines buried under the surface, or othermeans) to convey the power from the far side base to the Earthward side.

5.3.1

Long Distance Transmission Lines Assume that some form of transmission lines must beemplaced between the power base and the far side array. Working with the transmission designgroup design an emplacment system. Try for reasonable commonality with the machines used toemplace the power plots. The manufacturing operations at the power base must accommodatethe materials and support needs for installing the long distance transmission facility. Project theoverall level of operations (distance, soil moved, connections, made, etc.) and as much operationsdetail as possible.

5.3.2


Local Distribution of Cross-limb Power: Assume that power is brought from the cross-limb baseto the power base. That power must be fanned out and delivered to the various power plots withthe power base. Design the machinery and operations to implace this local power distributionsystem. Work closely with the power distribution design group. The needs are very sensitive tothe overall efficiency of the Reference Model, the use of LO mirrors, and the means of powerredistribution.

5.4 Lunar Orbit Facility

The facility(s) in lunar orbit provides logistical support, the gathering of bulk materials from thelunar surface, and the manufacturing and deployment of Solar Sails (optional).

5.4.1

Logistics: Identify the essential logistical activities of the Lunar Orbital facility. Translate thoseactivities into facility design requirements and project the level of manned support needed. Thescale of this facility with be senstitive to the overall efficiency of the Reference System and the useof lunar materials in support of space vehicles from Earth and to the Moon. Identify whether ornot the components and systems of the International Space can contribute to the LO Facility.

5.4.2

Mirror Production and Repair: Work with the LO Mirror design group and the glass productiongroup. Design facilities to make most of the LO Mirrors from lunar glass and metals. Assumepart of the control systems come from Earth. Design the assembly process. Estimate the level ofhuman support necessary. Pay very careful attention to providing radiation shielding for thehumans.

5.5 Earth Orbit to Lunar Orbit Transportation

Both cargo and human transporation must be provided between Earth orbit and Lunar Orbit andto the lunar surface.

5.5.1

The tonnage of cargo and means of transport will likely evolve quickly over the life-cycle of theReference Model. In this design study focus attention on the demonstration phase and earlyacceleration of implacement. Explore the full range of transport options that will minimizeupfront costs and operating costs. Explore the agressive use of bulk lunar soil in LEO to supportboth the cargo and human transport. Review past studies on Earth-moon transport.

Explore the phase in LSP System emplacement at which beamed power, microwave or laser,could be used to propell ion-drive cargo vessels between EO to LO. Carefully consider the


productivity of such vehicles and do not focus exclusively on engineering efficiency. Considersolar sails, tethers, and other means.

5.5.2 Human transport:

Protection against solar storms and chronic exposure to galactic cosmic rays is a dominateconcern for the travel of humans between Earth orbit and the Moon. Consider suggestions, suchas made by Dr. Buz Aldrin, for resonance orbit craft that permanently coast between the Earthand the moon. Examine the use of bulk lunar materials to provide radiation protection andpassively stable thermal environment.

Explore the design of “sprint”vehicles to transfer people from LEO to the passing resonantcraft(s) and then to the LO facility or directly to a Power Base Headquarters. Consider the use ofsolar energy, beamed power, and lunar materials in the operation, maintenance, and orbital controlof the resonance craft(s).

5.5.3 Facility(s) in Orbit About Earth

The EO facility will be a staging area for travel to and from the moon of people, cargo, andsupplies. Carefully examine the primary functions the facility must provide to supportconstruction and operation of the LSP System Reference Model. Develop flow rates, power,labor estimates, and related metrics in order to scale the size of the facility to the life-cycletransport needs of the Reference Model. Examine data on the International Space Station, Mir,Skylab, and the Shuttle Fleet.

Consider alternative approaches such as the large space facilities suggested by Ed Hysack, severalspecial purpose facilities, and growth of facilities using lunar derived materials delivered in bulk toorbit about Earth.

The facility will assymble and deploy redirector satellites. The facility may be used to maintainand repair redirector satellites.

Consider the facility as a place for production of electronic components such as proposed for theadvanced Wake Shield facilities proposed by the University of Houston (Center for SpaceVacuum Epitaxi).

5.5.4 Earth to Orbit Transport

High E/EO transporation costs increase the upfront cost of the LSP System Reference Model.However, given high productivity on the moon the high E/EO transport costs do not significanltyincrease the life-cycle cost of energy from the Moon. Reducing costs of transportation isimportant but just as important is reliability, flexibility in cargo tonnage and volumn, avoidingcommitment to a single launch system that might contain generic flaws, and minimizing ofenvironment impacts. Multiple launch providers and competition should be encouraged.

Develop traffic models of E/EO launch needs for the LSP System Reference Model. Be verysensitive to the affects of technology advancement of the Reference Model on launch needs.


Look carefully at the use of lunar materials in EO and lunar beamed energy and how those mightreduce E/EO launch requirements.

Examine the various United States (NASA, DoD, private) and foreign launch systems and studiesof proposed E/EO launch systems. Consider parallel booster configurations that can use commonhardware to accommodate a wide range of payloads, consider extremely large launch vehiles (oneway and reusable), consider extensions of semi-ballistic point-to-point commercial craft asproposed by Aerospace Corportation (1991).

Consider the possiblity that with high efficiency LSP components, use of lunar materials andbeamed power, and high production rates on the moon that an expansion of the present rate ofcommercial space launches and an evolved STS might provide adequate launch capacity.

5.5.5 Closed Environmental Life Support Systems

Consider the implications of providing closed or nearly closed life support systems for all humanhabitats. The primary inputs would be energy and make up materials from the moon andsecondarily from Earth. Include recycling of air, water, wastes, and food. Develop modes fordevelopment costs, operating costs, safety, mission flexibility, and other factors. Review NASAsponsored work on CELLS, lunar based agriculture, planning for the International Space Station,and Mir and Shuttle experience.

5.6 Send The Maximum Of Smarts And A Minimum Of Things

This is a challenge to all the Design Groups. The practical arts of automation and remoteoperations are rapidily advancing. The functional goal of the LSP System Reference Model is toconstruct an Enormously Large Integrated Circuit (ELIC) on the Moon from lunar resources.This ELIC is solar powered. Its output is carefully controlled beams of microwaves projected torectennas on Earth. Closely examine all the assumptions and designs of the Reference System.Evolve it toward simplier ELIC designs and quicker and cheaper means of producing ELICs. TheReference Model is based on late 1970s insights into the relevant technologies and procedures.Do better. This is an excellent area for good communications and joint projects between all thegroups.

6.0 DEMONSTRATIONS

Major resources will not committed to the LSP System Reference Model, or an ELIC, withoutappropriately scaled demonstrations of the key physical and engineering functions the ReferenceModel must sustain. These are:

• demonstrating that the Moon is a stable plateform for the high precision, completely controlledbeaming of power to rectennas on Earth (also - to redirectors in orbit about Earth and then toEarth);


• demonstrating the beaming and reception of commercial levels of power (~ Megawatts) ofpower through the ionosphere and atmosphere at appropriate power densities (10 to 200Watts/m2) and frequencies (~2.54 GHz) for economic and dependable operations; and

• demonstrating the production of required LSP components from lunar materials and theirdeployment (on Earth, in simulated lunar conditions, on the moon).

These topics are discussed in the following reference. There may well be other criticaldemonstration topics.

Criswell, D. R. and Waldron R. D. (1993b) International lunar base and lunar-based power systemto supply Earth with electric power. Acta Astronautica, 29, 469-480, Pergamon Press Ltd.

6.1 Completed Demonstrations

Many of the key technologies have been available for decades (thin film photovotaics, microwavegenerators, high temperature glasses (sheets, fibers, structural), printed circuits, etc.). Powerbeaming was demonstrated by NASA in the 1970s. However, that is simply a special case ofstandard operations in military phase array radars, large arrays in radio astronomy, space borneside looking radar, and others. The Apollo and USSR flights to the Moon demonstrated mannedand unmanned activities. Many of the above design studies specify examinations of availabletechnologies in their specific fields. Bring together the results of the above design studies andindependent examinations of the key technologies. Evaluate them in terms of their value as partialor complete demonstrations of key features of the LSP System Reference Model. Identify criticaltechnologies and demonstrations that are still required. Explore how to use available or readilymodifiable systems to do some or all of these critical demonstations.

6.2 The Moon as a Beaming Plateform

Confirm the moon as a suitable plateform for precisely controlled beams back to receivers onEarth and to redirector satellites in orbit about Earth. Also beam to satellites in high orbits (ex.ATS, Geo-Comsats, Russian Molynias, etc.). Explore doing this demonstration at the signal levelby using three to four unmanned craft on the moon. Land one of the craft at the central locationof a potential power base. Land the other craft at three locations evenly located around theperiffery of the power base. Each craft is solar powered and equipped with a master clock andnarrow band transmitter. The four transmitters are phased so as to send a signal level beam backto receivers on Earth. The system is deployed as soon as possible and operated for several years.Surveyor-scale craft can be used. Samples of key LSP components (photovoltaic cells, wiring,fiber glass, computer circuits, etc.) can be taken to the Moon for long duration tests.

6.3 Demonstrate Beaming Commercial Scale Space Power, Reflectors, and Rectennas

6.3.1


Develop a system level plan for demonstrating the beaming of ~ 1 Megawatt of microwaves froman existing large phased array on Earth to a reflector satellite in low orbit about Earth that reflectsthe beam back to a rectenna on Earth.

6.3.2

Examine in detail existing, large aperture phased array radars on Earth. Select one that can bemodified to project ~ 1 to 10 Megawatts of continuous microwave power for approximately 10minutes with a one to two hour recycle time. Design the engineering modifications that must bemade. Develop cost and schedule models for the modifications. Develop procedures and costmodels for the demonstation operations. It is preferrable that the beam be projected and receivedunder near-field conditions. However, this may not be possible.

6.3.3

Design a microwave reflector that can be deployed into LEO from an existing launch vehicle.This will likely be an inflatable with a diameter in excess of 100 meters. However, other optionsexist. Carefully consider such key factors as stability of the reflective surface, necessary minimumdiameter, beam frequency, duty cycle, pointing accuracy, drag, mission duration, and developmentcost. Consider options for active control of the reflective surface. Consider methods formaintaining the functional reflector in orbit for an extended time.

6.3.4

Design one or more types of rectennas for deployment “near” the phased array selected in 6.3.3.If possible select a radar site that can beam, via the orbital reflector, to areas with distinctclimates. For example, a radar one hundred kilometers from a coast or large lake might be able tobeam to rectennas that are respectively in a moist coastal zone, an ocean plateform, an island, adesert area, and to a high altitude site.

6.4 Materials Processing and Key Production and Assembly Processes

6.4.1

Considerable terrestrial experience exists in the primary industrial operations required to constructthe LSP lunar components. Lunar operational experience exists from Apollo landers and roversand the Lunahkod. A vast literature exists on the samples and data collected from the Apollosites and also from the Soviet landing sites. Many tons of simulated lunar soil are available. Withan extremely well argued case very limited quantities of actual lunar soil can be obtained fordemonstations. Considerable work has already been done in these topics. Check the literature.Space’96 (etc.) is a good starting point. Select and conduct bench level and prototype operationslevel demonstations in the following areas.

• Demonstrate the automatic/teleoperator preparation of a “typical” power plot. Include grading,scaping, rock handling, trenching, and digging and back filling.


• Grade and size lunar soils and lunar soil simulates.• Beneficate lunar soils (magnetic, physical, optical, electrical, etc.).• Melt soil simulates and produce bulk glasses from the bulk soil and various mineral and size

fractions.• Process lunar derived bulk glass into sheets, fibers, foamed glass and solid glass structures,

dense structural components, powder, and other forms. If at all possible try to characterize theproperties of these products in vacuum where the surfaces have little or no exposure to water orhydrogen.

• Recover volatiles from lunar soils and separate the useful gasses.• Recover iron from lunar soils as bulk metal, wire, and powders.• Form fiberglass mesh, coat the mesh with iron and/or aluminum, and attach the mesh to

structures required to form microwave reflectors.• Make, in a vacuum, photovoltaic array formed on lunar glass. Demonstrate the arrays in a

simulated lunar thermal environment through ~700 cycles of temperature, hard UV, and solarcosmic ray exposure. Include electrical connections and confirm the collection of power.

• Demonstrate the production, in vacuum, of bulk components of a microwave power unit (bothfor magnetrons and solid state systems).

• Demonstrate the automatic assembly and testing of microwave power units from lunar derivedand Earth supplied components.

• Demonstrate typical automatic/teleoperator assembly procedures to be used to construct apower plot.

6.4.2

Design and conduct a full scale terrestrial simulation of the construction of a power plot fromsimulated lunar materials. The most promising laboratory and bench studies can be incorporatedinto sets of autonomous, mobile production machinery for demonstrations on Earth. Theproduction equipment can be rover units of the general nature depicted in Figures 2. Perhaps theemplacer units can be scaled to be transportable by a class of aircraft with the cargo capacity ofthe U.S. STS or the Soviet Shuttle (< 30 tons payload). A C-130 is a possible analog.

The set of prototype production equipment can air-lifted to a high desert area. The plane landsand the prototype units are driven out under automatic or remote control. The production unitsthen go to a succession of sites to build power plots. Each site represents a different lunar terrainand soil type.

The sites are created in a set of inflatable buildings established in the high-desert area. Three orfour of the buildings are located along the perimeter of an elliptical area 10 to 100 km in diameter,and the last is located near the center. The roof of each building is transparent to sunlight and 10cm microwaves. The floor of each building is covered to a depth of one to two meters withsimulated lunar soil and rocks. Highland (aluminum-rich) and mare (iron-rich) areas aresimulated. The buildings are pressurized with an inert gas, and entry ways are provided for therobotic construction equipment.

This program could be a joint activity of many of the National Space Grant Consortia to the U.S.Congress.


6.4.3

Consider utilization of the International Space Station, the Mir, and the Long Duration Orbiters.

Evaluate the potential of the International Space Station as a platform on which to assemble andtest reflector and redirector satellites and from which to deploy such satellites to different orbits.These facilities can support R&D development of the larger orbital reflectors. Important tasksinclude verification of surface tolerances, demonstration of assembly and maintenance procedures,accelerated aging of key components, and demonstration of logistics support for the lunaroperations.

7.0 BOOTSTRAPPING

It may be possible to significantly reduce the upfront cost of the LSP System Reference Model byearly aggressive use of lunar materials to reduce the cost of transport between Earth orbit and themoon and by making significant fractions of the facilities and factories from lunar materials. Thisoption may increase the time to delivery of commercial power to Earth. However, it may enablefaster growth rates one power emplacement starts. This is a classical buy versus importantproblem in economics. Various ELIC designs may be especially amenable to Bootstrapping.

7.1.1

Review the facilities, factories, and materials needs in the foregoing sections. Determine whatfractions of these facilities, factories, and materials could be efficiently produced on the moonusing local materials. Identify the key production functions.

7.1.2

Using the results of 7.1.1 design production systems to make the high-leverage componentsderived from lunar materials.

7.2

Carefully examine the transportation systems for travel between the Earth and moon. Review thetransporation designs developed in the earlier studies. Develop and analyze systems that wouldmake efficient use of lunar materials in the earlies phases of an LSP program to provide reducedcost and safer transporation options.

7.3

Make use of the earlier cost and systems models to maintain consistent evaluations of the variousoptions. Specialize the engineering and cost model to analyze the import versus build optionsidentified in 7.1 and 7.2.


8.0 TWO-PLANET ECONOMY

The above sections have focused on how the Moon could be developed as a source of commercialpower for Earth and the potential benefits to Earth. The LSP System Reference Model, even at avery small scale, would establish the Moon as an integral part of the Earth’s economy and create atwo-planet economy between the Earth and the Moon.

8.1

What are the short term implications of even a small two-planet economy for the space programsof the world? Space projects could be conducted in an energy–, materials–, and resources–richenvironment. Apollo greatly advanced the scale of space science research. Consider radioastronomy, active space science experiments on the solar wind and ionosphere, deployment of alarge permanent research facility to orbit about Mars and/or Venus (using solar sails or beamedpower and low cost facilities based on LSP facilities), large telescopes on the moon, etc.). Howcan the technologies and systems to emplace the LSP System be used on asteroids and the moonsof Mars? What are the implications for scale and scope of effort, costs, and duration of presence?

8.2

In what ways could the LSP System contribute to the elimination of asteroids and comets as athreat to Earth? Examine the LSP System as a radar to scan the solar system for debri and as asource of power to deflect distant bodies that will threaten Earth.

8.4

What, if any, methods could an LSP System contribute to management of global climate changethat are independent of the biosphere? For example, solar sails placed between the sun and Earthhave been proposed by others as a means to fine-tune the solar flux to the Earth. Is this worthy ofdiscussion? Are there other possibilities?

commercial power from space need

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