converter is a GaAlAs solid-state converter, operating at 320 K, and having a power system mass of 520 kg. The rover power system would then have a specific mass of 21 kg/kW. Table VI shows a comparison of the Eagle Engineering fuel-cell powered, long-range rover with the results of the present study using a laser photovoltaic-powered rover. Both rovers use about 25 kW of power, but the fuel cell rover is limited to a round trip range of 3000 km, unless additional fuel cell reactant mass is added. Since there are no power system expendables with the laser photovoltaic system, virtually unlimited range can be achieved (dependent primarily on crew needs). The present study has not attempted to define the total laser rover mass, but it would certainly be less than the 17,500 kg fuel cell mass. If a comparison is made between the rover power system only, then the laser rover power system is a factor of 10 below the fuel cell rover. Finally, the prime power sources for the rovers are significantly different. The fuel cell rover demands the placement of an II2-O2 plant on the lunar surface with considerable mass investment. Alternatively, the laser prime power system would be in lunar orbit where it could be more flexibly used. Our scenario requires that three laser power stations be placed in lunar orbit having a total mass of 15,000 kg. The laser power transmission concept provides a lunar power infrastructure which is highly flexible in its ability to provide power to any point on the lunar surface. The reactor prime power source remains in orbit where it can be safely maintained and easily moved to other orbits for beaming power. Significant mass saving and flexibility is also achieved on the rover using laser power transmission. REFERENCES [1] J. Cintala, P. D. Spudis, and B. R. Hawke: "Advanced Geologic Exploration Supported by a Lunar Base: A Traverse Across the Imbrium-Procellarum Region of the Moon." Lunar Bases and Space Activities of the 21st Century (W. Mendell, ed.) Lunar and Planetary Institute Press, p. 223-237, 1985. [2] M. S. El-Genk, N. J. Morley, R. Cataldo, and H. Bloomfield: "Preliminary Assessment of the Power Requirements of a Manned Rover for Mars Missions." 2nd International Conference on Engineering Construction and Operations in Space - Space 90, Albuquerque, New Mexico 23-26 April 1990. [3] K. A. Faymon, M. Perez-Davis, and L. L Kohout: "Power System Concepts for Lunar Surface Mobile Equipment." Lunar Bases and Space Activities of the 21st Century, LBS-88-009, Houston, Texas, April 1988. [4] Eagle Engineering, Inc.: "Lunar Surface Transportation System Conceptual Design, Lunar Base Systems Study Task 5.2." NASA CR-172,077, July 1988. [5] R. J. De Young (ed.) "Second Beamed Space-Power Workshop,” NASA CP-3037,1989. [6] S. Aftergood: "Background on Space Nuclear Power." Science and Global Security, Vol. 1, pp. 93-107, 1989.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==