Electrical Power System design for a Lunar Outpost

“The directive I am signing today will refocus America’s space program on human exploration and discovery. It marks a first step in returning American astronauts to the Moon for the first time since 1972, for long-term exploration and use. This time, we will not only plant our flag and leave our footprints, we will establish a foundation for an eventual mission to Mars, and perhaps someday, worlds beyond". -Donald Trump In December 2017, with these words, the President of the United States of America set a turning point in the space exploration program, establishing the human exploration of the Moon as top priority of the National Aeronautics and Space Administration (NASA) for the 2020s. This undoubtedly lead also the global space industry to consider the manned exploration of the Moon as target for the next decade and, in this context, was born the idea of the thesis: design the power system of a lunar outpost designated to provide power to robotic rovers, which have the task to prepare the site to sustain human life in the early phases of the lunar exploration program. The work started with an in-depth study of the past space missions, with a particular focus on their profiles and the correspondent energy storage choices, and advanced with an analysis of the energy storage technologies, including the evaluation of present and future performance. The outcome of these research allowed to choose the most suitable technology for the lunar mission, designed to be part of the precursor robotic program. The most appropriate choice turned out to be the Fuel Cell: an electrochemical device that generate electrical energy from a reaction in which oxygen and hydrogen combine to create water. This technology have been already used in the 1960s as primary source of electric power in the Apollo mission but, even if that choice was driven by the need of drinking water for the astronaut crew, it should be considered as a valid energy source also for future lunar space missions thanks to the expected technology improvements. The project ended with the design of the Power Conditioning & Distribution Unit (PCDU) at architectural level, focusing on the low temperature performance of its components in order to estimate its efficiency. This allowed to evaluate the overall performance of the designed Electrical Power System (EPS), which are discussed in the final chapter of the dissertation. This document follows the same logical procedure just described: it starts with the "History of space exploration and power system design" chapter, continue with "Energy storage technology", "Lunar mission definition" and "Power system design" chapters and is completed by "Conclusion" chapter. This work can be considered as a starting point for future design of Lunar outposts: with a more precise definition of the mission and, consequently, of the driving requirements is possible to refine the design of the power system obtaining an appropriate, performing solution.