I was struck by something while watching the film The Martian recently. In the movie, Matt Damon’s character is stranded on Mars and survives, in part, by using solar modules as an energy source. It struck me that the exact same modules that work on Earth would also work on Mars—or, for that matter, on any planet in our universe that’s close enough to a sun where sufficient sunlight can get through its atmosphere.
As I understand it, the Martian atmosphere receives about half the average insolation as Earth’s. But Mars has a thin atmosphere and very few clouds, so approximately the same amount of insolation gets through to the surface, at least near the equator. (Dust storms are a serious problem, though; they can easily smother an array to the point where no current is produced.)
Realistically, getting an array to Mars that’s large enough to support even a small colony would be a formidable challenge due to its weight and size. Thin films might provide a partial solution here; they’re lighter and more compact, though today also less efficient. The weight of the racking and BOS components needs to be factored in, too, of course.
Then again, what’s the alternative? Wind, hydro, geothermal, and fossil fuels obviously won’t work on Mars. Nuclear could, though I imagine a reactor would be difficult to transport to Mars. Hydrogen fuel cells could work, too, but you’d need to transport and store (or create) hydrogen.
Without a doubt, powering a Martian colony would be a daunting technical challenge no matter what energy source is employed. But solar power is a compelling option on its face for several reasons. Off-the-shelf, mass produced, inexpensive modules would generate power on Mars. Conventional PV modules are reliable since they have no moving parts. They pose no significant risks in the dangerous frontier of space (i.e., they can’t explode). If they’re damaged by small meteorites or dust storms, they can be easily swapped out. Unlike nuclear reactors, they don’t require engineers to install or operate. And arrays can be deployed quickly, using simple tools, just as they are on Earth.
All of these factors are undoubtedly seductive to those who plan space missions. I just hope I live long enough to see an array installed on Mars.