The three-day meeting of experts is taking place this week, sponsored by the school, NASA and the Lunar and Planetary Institute.
Growing fields
On Earth’s moon, thin-film silicon-based solar cells can be made from silicon, iron and other materials generated from the processing of lunar regolith.
Engineers have proven the concept with lab experiments, said Alex Ignatiev, director of the Space Vacuum Epitaxy Center at the University of Houston in Texas. Using simulated lunar materials called "simulant" -- geochemical copycats of lunar surface samples brought back by Apollo astronauts -- solar cells have been grown, he said.
"The silicon was relatively good -- not fantastic, but good enough," Ignatiev told SPACE.com.
Making solar cells from lunar simulant is "almost a no-brainer," Ignatiev said.
Refined silicon can be directly vacuum evaporated on the Moon through solar heating, thereby creating thin films of silicon. These thin films can be doped and covered by contact electrodes and anti-reflection coatings to generate a solar-cell structure.
While the cell’s power output is not high compared to devices made here on Earth, quantity can make up for lack of efficiency, he said.
Walk before you crawl
Work is now under way, Ignatiev said, to design a special lightweight robotic crawler that slowly moves across the lunar surface.
Outfitted with sets of solar collectors, the rover migrates over the Moon, harvesting the lunar topside it rolls over. By using melting, evaporating and depositing processes, the crawler lays down solar cells atop the lunar landscape.
"We’re not making the best solar cells in the world, just adequate ones to do the job," Ignatiev said. Two hundred kilowatts of solar cell capacity can be made in a year, requiring just 396 pounds (180 kilograms) of raw lunar material, he said.
Given additional crawlers, more solar cells can be manufactured yielding multi-megawatts of available power.
A similar technical approach could also work on Mars with modification, Ignatiev said. Such an autonomous electric power system would allow for
presence in space independent of Earth, he said.
Commercial interruption
Power production facilities on the Moon could serve as an electric power grid for myriad functions.
Lunar bases, replete with oxygen and rocket-fuel-making plants, can be energized. Scientific equipment can be operated. Electricity can even be exported off the Moon, beamed to an energy-hungry Earth or to other locales about the solar system.
But many workshop experts said that any lunar "power play" is inherently a commercial enterprise. Nonetheless, initial customers may be governmental.
G. Jeffrey Taylor, a lunar and planetary scientist at the University of Hawaii in Honolulu, agreed that getting back to the Moon is now a private affair.
"The only way we’re going back to the Moon is for commercial reasons. Something big has to come along to replace all the Cold War reasons that drove us to the Moon in the first place. The Cold War is over," Taylor said, "and now it’s going to have to be commercialization. It has to be."
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