But for Mars outposts closer to the poles, the required solar equipment would weigh more than 20 tons. Mars is tilted about 25 degrees on its axis, slightly higher than Earth, and its orbit is less circular, so less sunlight reaches these photovoltaic cells during parts of the year. This means that nuclear power becomes more feasible at the poles. The power-generating equipment needed to generate this much nuclear power would add up to about 9.5 tons of carry mass to produce the same 40 kilowatts of energy. That kind of lift is feasible for large next-generation rockets like NASA’s Space Launch System and SpaceX’s Starship and Super Heavy, each of which can send payloads of at least tens of tons into deep space. (The poles also harbor ice, which could provide water for astronauts.)

These same types of trade-offs are already present in the energy technologies used by Mars rovers. Engineers need to find the right balance between shipping weight, storage needs, and an energy system that can handle changes in sunlight availability. Guillam Angrada-Escud, an astronomer at the Barcelona Institute for Space Sciences, who was not involved in the study, said a lot of sunlight would only arrive on Martian day, and only if dust and cloud particles were out of the way. surface. He is also a member of the Sustainable Unworlds Network, a network of researchers, engineers and architects studying how future colonies on Mars and other worlds work.

Anglada-Escudé agrees with Abel and Berliner’s findings. He also believes that solar and nuclear should not be viewed as either, if possible. “Our conclusion is that you want to have both solar and nuclear,” he said. “It’s a question of resilience. Things can fail in many different ways. The best option is redundancy.”

Daniel Vázquez Pombo, an energy engineer at the Technical University of Denmark who wrote a paper last year, said it was also important to study how solar radiation and how dust and ice affect the amount of light reaching the Earth’s surface and the best places to collect it. On a potential hybrid system for permanent Martian colonies, including photovoltaic arrays and storage. Maintenance of the energy system can be risky for those who do it, another argument for being selective.

“Do you really have to rely on a single technology? What happens if you have a system bug or a design flaw,” Pombo said. “Diversification is a smart idea. You don’t put all your eggs in one basket.”

Anglada-Escudé believes the calculus could also change when it’s not just a handful of astronauts visiting for a few months or a year, but a permanent colony with long-term visitors. “Solar panels are a relatively simple technology, and in the long run, solar will become more attractive,” he said. “You might need more mirrors, but it will work. On Mars, finding the mass of plutonium needed for a reactor is not easy. The solar energy is there, it’s safe, and we know how.”

Ultimately, life in the rugged environment of Mars will be tougher than anywhere else on Earth. Tech issues are only half the story. Settlers also had to deal with complex financial and social issues, Abel said. At least when they get there, though, they’ll know how to keep the lights on.