Here’s How Martian Explorers Could Best Produce Electricity on the Red Planet

Scientists are on the fence as to whether solar or nuclear should be the preferred source of power for small teams visiting the Martian surface. New research suggests both options are good, with geographical location being the determining factor.

The researchers compared two different power-generating options for a crewed trip to Mars: solar cells and nuclear power from small fission reactors. A key consideration was the amount of weight, or “carry-along mass,” required to build each solution, as missions to Mars will seek to pack in the most efficient way possible. The results, published today in Frontiers in Astronomy and Space Sciences, suggest both options are viable, but with a rather important caveat having to do with geography.

“The main result was that which one ‘wins’ depends on the location on Mars,” Anthony Abel, a researcher from the Department of Chemical Engineering at UC Berkeley and a co-author of the study, explained in an email. “The overall result was that nearer the equator, solar was better than nuclear, while nearer the poles, nuclear was better than solar.”

This is good information to have, as it could have significant bearing on the type of power-generating devices that each future mission will want to bring to Mars. NASA should take note, as the space agency is planning to send the first crewed mission to planet in the late 2030s or early 2040s. That said, these findings are specific to a six-person crew on a 480-day mission to the Martian surface (the first missions won’t likely last longer than 30 days), but the researchers say their results could speak to even larger and longer missions, including permanent colonies. Aaron Berliner from the UC Berkeley Department of Nuclear Engineering is a co-author on the study.

Future explorers will need electricity to support their ground missions. This power will be needed to generate warmth, oxygen, and clean drinking water, as well as to also power more advanced activities, such as LEDs to shine on crops and 3D printers to churn out useful parts. Abel and Berliner, as members of the Center for the Utilization of Biological Engineering in Space (CUBES), have a vested interest in this subject, as their imagined concepts will depend on sustained power to work, such as the use of microbes to produce plastics and pharmaceuticals. Abel and Berliner wanted to know how to best provide power to their future space-enabling systems, leading to the new study.

“We knew that rovers in the past had been powered by either solar cells or nuclear power generators, and that both solar and nuclear had been proposed for crewed missions to Mars,” Abel told me. “Nuclear generators will work more or less the same regardless of where you are, but solar cells will operate pretty differently because sunlight is the source of power.”

The consistency of nuclear and the tenuousness of solar has led some experts to suggest that nuclear might be the smarter, more reliable choice. Indeed, there are many factors to consider when it comes to generating solar power on the Red Planet. Mars, in addition to being farther away…