Researchers at the University of California, Berkeley, have found that solar power might be the ideal solution to power prolonged — or even permanent — visits to Mars. 

Until now, many engineers and scientists believed that nuclear power would be the better solution; however, advancements in photovoltaics show that solar could prove better if not comparable to nuclear power. 

For the study, the team looked at a six-person mission to Mars that included 480 days spent on the surface, a likely scenario that would reduce the time it takes to travel planet-to-planet. 

The researchers found that for sites on about half of the Martian surface, especially around the equator, solar power would be better than nuclear power, especially when you consider the weight and efficiency of solar panels. Of course, this is contingent on the power source’s ability to produce hydrogen gas to be used in fuel cells that will power the settlement at night or during sandstorms. Dust is a problem on the red planet and the main reason solar fell out of favor. If you recall, it was a dust storm that knocked the solar-powered Opportunity rover offline in 2019.  

The researchers are part of the Center for the Utilization of Biological Engineering in Space (CUBES), a multi-university effort to use genetically engineered microbes to produce food, rocket fuel, plastic materials, and chemicals in space. That kind of biomanufacturing will require a lot of power.  

After crunching the numbers, photovoltaic power with electrolysis, or using electricity to split water into hydrogen and oxygen, was competitive with nuclear power. Much of it comes down to weight and reliability. For example, the mission would be able to carry enough lightweight solar panels aboard the craft to even have a backup or get the same performance as a Kilopower nuclear reactor system while saving 1.2 tons on the trip over. Also, if you have multiple panels, you have a solution if one goes down. If the nuclear reactor goes down, the colonists would be in trouble. 

All of this work is critical to human survival on the red planet as well as future exploration.