IAC 09 C3.4.5 SUSTAINABILITY ON-ORBIT: SPACE SOLAR POWER AND CLOUD COMPUTING CONSTELLATION TWO EXAMPLES OF INTERNATIONAL OFFSET PROJECTS

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1 IAC 09 C3.4.5 SUSTAINABILITY ON-ORBIT: SPACE SOLAR POWER AND CLOUD COMPUTING CONSTELLATION TWO EXAMPLES OF INTERNATIONAL OFFSET PROJECTS Author: Mr. Sean Mobilia Global Enterprise Initiative (GEI), Moffett Field, California, United States Coauthors: Ms. Tuyet Le Global Enterprise Initiative (GEI), Moffett Field, California, United States Mr. Jim Grady Global Enterprise Initiative (GEI), Moffett Field, California, United States Dr. Periklis Papadopoulos Space Systems International, San Jose, California, United States Mr. Lee Lunsford Lunsford Consulting, Sunnyvale, California, United States ABSTRACT Space-based solar power (SBSP) and Cloud Computing On-Orbit (CCO) are two examples of international offset projects underway at GEI applicable to sustainability. Others include UAV/satellite forest fire monitoring, international students/post-doc research, sustainable green construction, point-to-point sub-orbital flight, ocean monitoring, autonomous SoC development, and bio-fuels and other biotech projects. Offset projects can take advantage of resources made available during large international procurements. SBSP has been talked about many times since Peter Glaser's invention of the concept over 40 years ago, however there still has not been a single SBSP watt transmitted down from orbit. Students at San Jose State University have been researching the feasibility of a SBSP demonstration, using either the International Space Station or a small satellite in LEO. This demonstration will be modular, to allow for many different possible component parts. The research for the SBSP demonstration has also helped to develop the concept of on-orbit cloud computing, and both concepts can be utilized for lunar applications. The SBSP demonstration is important because the necessary efficiencies and losses have not yet been clearly established and is being developed to beam 200 watts of power to Earth's surface, estimating 25% efficiency due to atmospheric losses and laser conversion losses. All technology needed for the demonstration exists. The cost, schedule and other programmatic elements of this demonstration will be provided. International offset can be a source of funding for this demonstration. SBSP and on-orbit cloud computing are both important concepts involving sustainable energy, thereby contributing to world peace, because they both make use of the abundant, renewable energy source of the Sun. Introduction Space-based solar power and Cloud Computing On-Orbit are two examples of international offset projects underway applicable to sustainability and are very relevant to the recent increase in interest in commercial space. Commercial space projects are applicable to international offset because they compensate customer countries for perceived economic losses, which is inherent in the rational for. offset. As discussed on the GEI website ( examples of space related international offset projects include the Svalbard ground station in Norway and flying a Malaysian astronaut to the ISS. The business cases for both space-based solar power and cloud computing on-orbit depend on an international strategy to ensure commercial viability.

2 Figure 1: GEI Offset Projects, Commercial Space Examples. Table 1: International Offset Definition / Terminology. Figure 2: Example of Space-Related Offset, Svalvbard, Norway Satellite Ground Station. Figure 3: Example of Space-Related Offset, Malaysian Astronaut to ISS, late Space-based solar power (SBSP) has been talked about many times since Peter Glaser's invention of the concept over 40 years ago, however there still has not been a single SBSP watt transmitted down from orbit. Students at San Jose State University have been researching the feasibility of a SBSP demonstration, using either the International Space Station or a free flyer small satellite in low Earth orbit. This demonstration will be modular, to allow for many different possible component parts. Along with this demonstration, the students have been researching on-orbit cloud computing. Much of the technology for the SBSP

3 demonstration is directly applicable to on-orbit cloud computing. On-orbit cloud computing involves multiple small satellites connected through optical communication links. This constellation of small satellites functions as a cloud computing grid. Just as SBSP involves the transmission of a modulated (modulated to ensure proper lock-on to a receiver and safety) beam from space to ground or space to space to provide power to another satellite, an on-orbit cloud computing small satellite node transmits modulated beams to other satellites and to the ground. One of the reasons this demonstration is important is because the necessary efficiencies and losses have not yet been clearly established. The cost, schedule and other enterprise elements, including use of international offset and other innovative funding approaches, will be provided. Background The optics for a space-based laser can be sized with Rayleigh s Criterion. While sizing optics for laser assisted solar sails, Taylor, Anding, Halford and Matloff (2003) give Rayleigh s Criterion as: Dreciever 2.44 (1) SEP D las receiver,max optics where D receiver is the diameter [m] of the receiver spot, SEP las-receiver,max is the maximum separation [m] between the laser power transmitter and the receiver, D optics is the diameter [m] of the laser transmitter optics, and λ is the wavelength [m] of the transmitting laser. θ is the angle subtended by the receiver at a given separation. Figure 4: GEI s International SBSP Initiative (ISI) Concept Demonstrations: Preliminary Mission Architecture.

4 SBSP Mission Architecture Space Based Solar Power (SBSP) is a method of harvesting clean, limitless energy and reduces the need for the destruction of the environment for the purpose of meeting increasing energy demands. SBSP requires the assembly of an expansive network of solar panels in geosynchronous orbit about the Earth. Placed in a high orbit where solar energy is intense, these solar cells would gather the sun s energy almost twenty four hours a day and 365 days a year. Once collected by the solar panels, this endless supply of energy could be beamed down to earth ground stations all over the world, including rural, undeveloped areas in third world countries. Universities in the U.S. and other countries have been researching the feasibility of a SBSP demonstration, known as the International SBSP Initiative (ISI). The objective of the ISI is to beam SBSP watts down to the surface from orbit while utilizing international collaboration and cheap, commercial components. In a swords to plowshares approach, ISI takes advantage of technology developed over a decade ago for the Strategic Defense Initiative (SDI) Star Wars program. This involves using laser technology onorbit as depicted in the following figures for the demonstration mission, with its international and educational objectives. Figure 7: Further ISI-SDI Comparisons. One of the possibilities for the development of the ISI is operation as an ISS payload. The ISS concept includes the following systems: the laser system; the acquisition, tracking, and pointing system; the ISS interface; the safety and control system; and the ground station receiver. The ISS concept is being developed as a 100kg payload that operates on 2.5 kw of power. Figure 5: ISI Takes Advantage of SDI Technology. Figure 6: Another ISI-SDI Comparison. Figure 8: Thermal Analysis of the ISI on the ISS Japanese Experiment Module (JEM). The ISI is also being developed for possible operation as a free flyer. The free flyer concept includes the following systems: the laser system; the acquisition, tracking, and pointing system; the instrument bus; the safety and control system; the propulsion system; the power system; and the ground station receiver. The ISI is being developed for use with existing, off the shelf technologies. The ISI is being developed with modular architecture, to allow for interchangeable components parts, and multiple possible demonstrations. The laser system is currently being developed for use with Southampton Photonics, Inc., (SPI) 400 W fiber laser. For the

5 purpose of the ISI flight demonstrations, 2 modules of the laser will need to be coupled together to achieve the desired power. The ISI is also being developed for use with the Saab Management Unit (SMU) for command and control functions. The power system for the free flyer is being designed for use with Micrel, Inc., solar concentrator cells. The acquisition, tracking, and pointing system; the safety and control system; and the ground station receiver systems are being developed based on existing technologies that will be integrated into the ISI flight demonstrations. The ISI flight demonstrations are being developed estimating 25% efficiency due to atmospheric losses and laser conversion losses. For the ISS concept, the system is expected to use 2.4 kw to power the laser. After loses due to the atmosphere and energy conversion, the system is expected to collect 200 W of power at the surface. For the free flyer concept, the system will collect 4 kw of power from its solar cells, allocating 2.4 kw to power the laser system. This will transmit 200 W of power to the surface. Figure 9: Cloud Computing On-Orbit. Cloud Computing is a method of computing that utilizes distant servers for data storage and management, allowing the device to use smaller and more efficient chips that consume less energy than standard computers. Figure 10: Cloud Computing Facilities on the Columbian River. Table 2: ISI Demonstration Summary. Cloud Computing On-Orbit Mission Architecture Cloud Computing On-Orbit is to a large extent the information technology (IT) analog to SBSP. However, instead of beaming down watts, the energy is used on-orbit and ones and zeros are beamed down to Earth. This changing of energy to bandwidth on-orbit, of course, alleviates problems associated with the large and growing amount of electrical power needed for ground based cloud computing facilities. Figure 11: Fiber Optic Links to the Columbia River Area.

6 Figure 12: Cloud Computing On-Orbit Description. On-orbit cloud computing involves multiple small satellites connected through optical communication links. These small satellites will house payloads of computer servers, which when linked, will combine their computing power to execute programs and applications. This can also give access to internet and computing power to areas where it is difficult and expensive to establish fiber optics and internet connections. One of the concepts of the ISI flight demonstrations will be developed to incorporate a laser communication demonstration to test the capability of an optical/data linkup, and perform minor computer applications. The ISI laser communication demonstration is being designed to incorporate TESAT s Laser Communication Terminal (LCT). Lunar Applications SBSP and on-orbit cloud computing can also be used in lunar applications. Power systems for potential lunar applications would require a significant cost. SBSP can be a system to collect power and transfer to individual lunar installations without significant infrastructure costs. On-orbit cloud computing concept can also provide communication and computing capabilities to separate installations without extensive infrastructure, as well as help maintain contact with Earth. Figure 13: ISI to Make Use of Commercial Technology.

7 Figure 14: Cloud Computing Lunar Orbit. Conclusion SBSP and on-orbit cloud computing are both important concepts involving sustainable energy, thereby contributing to world peace, because they both make use of the abundant, renewable energy source of the Sun. These concepts, which are viable potential offset projects, can be used to provide power or information directly to places that are underdeveloped.