I defer to Rocketguy who is a literal rocket scientist. But I don’t think so. Certainly it wouldn’t be a regular source of energy. Even solar isn’t a regular source of energy.

You would need to concentrate the particles, thus solving both problems, the radiation hazard, and the heat from the decaying ions to generate electricity. But if here on earth where we have the magnetic field to possibly achieve this, no one has figured out a practical approach. Of course, if you could provide Mars its own molten iron core, it’s rotating as fast as the earth, and its own field would shoot up in strength.

Available solar energy at the surface of Mars is still about half of what is available on Earth, so solar energy is still very much a practical way to create energy.
That is why the rovers actually have solar panels.

@stanleybmanly So the issue is that the gamma particles are too dispersed to be useful in energy production. Could they build a large parabolic dish, something like the Arecibo Observatory radio telescope to reflect the particles into a single point?

@ragingloli Well one of the issues with solar, besides the diminished levels, is the accumulation of dust, as well as the massive dust storms. That wouldn’t impact a radiation based electricity production system would it?

@Caravanfan I’m guessing this wouldn’t work (because they’d probably be doing it if it did). I’m just trying to understand where my assumptions are wrong.

You would need a means of absorbing the various species of radiation (gamma, cosmic rays, etc.) and converting them to electricity. I don’t know of any efficient conversion method for them. They are not that intense anyway, just bad for humans and electronics. The most intense EM on Mars is probably solar, between IR to visible to UV. Solar cells can convert IR-visible into electricity. I haven’t seen high efficiency with UV.

Thanks for all of the great answers guys.

@RocketGuy I did find this paper that describes a device that can convert radiation to electricity. Maybe the applications are more useful in space for a probe than on the Martian surface?

Seems like a way to scavenge gamma rays that would otherwise be wasted. Their gamma cell produces up to 200 microwatts/m^{2. The average solar cell produces around 200 watts/m}2 on Earth or around 100 watts/m^2 on Mars. So 0.1–0.2% the capability but that energy was previously uncollected. I suppose you could run a radiation warning LED flasher with that power.