Nanotechnology, Space and Energy for the World Alex Ignatiev and Alex Freundlich

1. Nanotechnology, Space and Energy for the World Alex Ignatiev and Alex Freundlich Center for Advanced Materials University of Houston Astana, Kazakhstan July 1, 2010

2. Smalley’s Pyramid: 10 Greatest Global Issues

3. Major Need for Earth: Electrical Energy • Over 2 Billion people have no access to electricity • Will need 20 TW of capacity by 2050

4. Breakdown of Incoming Solar Energy

5. The Solar Spectrum • Power Density Reaching Earth = 1.37 KW/m2

6. Solar Spectrum Utilization: Solar Cells

7. Solar Cell Landscape • First Generation • Silicon • Less than 20% efficiency • ~$3/watt • Second Generation • Thin film • Less than 15% efficiency. • ~$1 - $2/Watt • Third Generation • GaAs based cells • > 500 suns concentration • 30% to 40% efficiency. • ~$0.40 - $1/Watt • All prices are cells only – excluding balance of system

9. Future Commercial Module Performance Based on today’s champion cell results and a module/cell-ratio of 80%

10. Solar Cells 2010 Market Share Estimate

11. Game-Changing Solar Technologies

12. Annual PV Market Outlook by 2030 8.9% of Global Energy, 1,864 GW Production Capacity, 2,646 TWh Electricity

13. Kazakhstan to Expand Into the Solar Marketplace

14. Solar Irradiation

15. Kazakhstan Minerals Important for Solar Cells Copper Titanium Gallium Indium Selenium Tellurium Zinc Cadmium Molybdenum Silicon

16. - Which Cell Technology to Use…??

17. Future Commercial Module Performance Based on today’s champion cell results and a module/cell-ratio of 80%

18. Why Choose CIGS • CIGS has the highest demonstrated (lab) efficiency of thin-film cells at 19.2% • CIGS can be deposited on flexible substrates - lightweight flexible modules • No inherent material limitations or hazardous chemicals

19. CIGS Champion Modules

20. PV Energy Costs

21. Solar PV Value Chain Material

22. PV Energy Costs • How to Reduce Costs..? • Reduce Production Costs • Increase Efficiency • Increase Time of Operation…… • Weather • Short Day-Night Cycle • Convert Solar Energy in SPACE…..

23. Use of Natural Satellites • The Moon • Use Moon’s Resources • Use Moon’s Stable Platform • Solar Energy From Space • Many Proposals on Converting Solar Energy in Space to Electricity and Power Beaming Back to the Earth • Use of Man-Made Satellites • Manufacture Solar Cells on Earth and Launch to Satellite….. Resources

24. CAM Center for Advanced Materials University of Houston • Solar Energy From Space • Use of the Moon • The Moon’s Resources • The Moon has most ALL Raw Materials Needed to Fabricate Solar Cells • Silicon • Aluminum • Gallium • Arsenic • Phosphorous • TiO2 • ‘Glass’

25. Solar Energy From Space • Use of the Moon • The Moon’s Resources • The Moon has a Unique Ultra-high Vacuum Environment Within Which to Fabricate Solar Cell’s • ~ 10-10 Torr (day) • Reduced Contamination During Processing • Reduced Processing Complexity – No Vacuum Chambers Needed • Increased Flexibility in Process Choice

26. Use of The Moon to Fabricate Solar Cells • Solar Cell Material Abundances • Silicon ~ 460,000 ppm • Aluminum ~130,000 ppm • Ga ~ 1 ppm • As ~ 1 ppm • Cd ~ 3 ppm • S ~ 1,000 ppm • Te ~ 200 ppm • Silicon Most Abundant Semiconductor – Silicon Solar Cells

27. Top Electrode and Anti-reflect n-Si Emitter ~ 0.5 m p-Si Base ~ 20 m Substrate and Bottom Electrode – Regolith Glass • Fabrication of Thin Film Silicon Solar Cells • on the Moon • Microcystalline Si Cells • Low efficiency ~5 - 8% • Make many cells • Needs • - Substrate – regolith glass • - Bottom electrode – Al, FeSi • - Si p-n junction – dopant • - Top patterned electrode – FeSi • - Antireflection layer – regolith glass, • TiO2 • - Interconnection of • individual cells – FeSi, Fe

28. Fabrication of Solar Cells on the Surface of the Moon from Lunar Regolith • Mechanized Solar Cell Growth Facility – Cell Paver • - ~ 150 - 200 kg • - Evaporation energy from solar thermal collectors • - PV panels for motive/control power • - Continuous lay-out of cells on lunar • surface • - Remotely controlled

29. Substrate - Melted Regolith ‘Glass’ • Bottom Electrode – Al or FeSi • Fabrication of Solar Cells on Moon • Solar Concentrators to Supply Thermal Energy for Fabrication • Silicon – co-doped • Metallization - Top Electrode • - Al or FeSi • - Evaporation through contact mask (electrode pattern) • Anti-reflection Coating • - TiO2 , SiO2, or evap. Regolith • Cell Interconnects/Power Grid • - Thin film metals (Al, FeSi, Fe, Ca….)

30. Make More Solar Cells • Fabrication of Solar Cells on the Surface of the Moon from Lunar Resources • 1 m2/hr • Fabricate ~ 65W/hr @ 5% and AMO (~1300 W/m2) • Assume 35% uptime (~3060 hrs/yr) • Fabricate ~200kW/yr capacity • Require ~ 100kg of raw materials (Si)/yr • Continuous Cell Replacement – Self Replicating System • - Assume limited cell lifetime • . Radiation damage • . Particle damage

31. Regolith Materials Extraction for Production of Solar Cells on the Surface of the Moon • Regolith Processing Facility: Si and Metals Extractor • - ~ 150 kg • - Regolith scoop • - Solar thermal and electric heat (connect to solar cell field) • - Recycle electrolyte (electrochemical reduction) • - Transfer oxygen and volatiles - Feed solar Cell Paver(s) . ~ 10 kg reactor  ~150kg/yr @ 500W . Small Support Rover to feed Cell Pavers

32. Production of Solar Cells on the Surface of the Moon • Ultra-high Vacuum on Lunar Surface Allows for Direct Thin Film Solar Cell Production on the Moon • - Less Mass (cost) to the Moon – 1 MW @ < 1/10 Cost • - Lunar Resources Utilized for Cell Production • - Trade-off Cell Efficiency with Quantity • Power Generation and Power Grid on the Moon • 10 Rovers  > 4 MW/year • Initially Use Power on the Moon for Lunar Needs

33. Production of Solar Cells on the Surface of the Moon • Advanced Lunar Power System • Mark II Cell Paver • 8% efficiency thin film silicon solar cells • ~6 m2/hr • ~2 MW/yr per Paver • 100 Cell Paver II operating for 5 years 1 GW Capacity • How to Use 1 GW of Solar Electricity on Moon..??

34. Use Lunar Solar Energy on theEarth • Power Beaming of Energy to the Earth….. • Beaming Stations at Lim of Moon • Laser • Microwave • Always ‘see’ Earth • Relay Satellites at Earth • HEISS Orbit + Equatorial • Need Transmission Efficiencies  70%

35. Power Beaming to Earth: Challenges • Microwave • Beam Spread over Long Distance • Large Transmitter • Large Receiver • Only Moderate Present-day Efficiency • 55% - 60% • Laser • High Power Density – pointing accuracy … • Efficiency ~25% - 30% • Solar Cell Placement • Require TWO Solar Cell Fields/Transmitters for 24hr Coverage (near Lims) • Require Relay Satellites • Minimize Loss in Relay

36. Feltrin & Freundlich, Renewable Energy, 13, 180 (2008) • Future of Solar Cells • Materials Availability……?? • Earth-extracted Raw Materials Limited….

37. Abundance Limits on Solar Cell Energy Generation Feltrin & Freundlich, Renewable Energy, 13, 180 (2008)

38. Conclusion • Solar Energy Will Positively Impact the World Energy Needs • Kazakhstan Can and Must Enter the Solar Energy Arena – Both in USE and PRODUCTION • We Can Effectively Utilize the Space Environment for Energy Generation for Earth • We May Need to Go to Space for Future Resources