Radiation Cells

[seer]

I was just watching the Weekly Space Hangout and they were talking about space probes using solar cells to save on plutonium. It got me to wondering why we don't have cell that can use other radiation. I heard that Jupiter puts out loads of radiation. Why can't we use that?

[AntennaGuy]

1. The visible light from Jupiter is simply reflected light from the sun. So the sun is the primary source. (Earth's moon is actually unusually bright, but good luck using that reflected sunlight to gather much power via solar cells.)
2. Solar cells require photons with sufficient individual energy to kick electrons between bands in certain semiconductors. Longer wavelength (e.g., infrared) photons (such as might be emitted by cooler objects) don't carry that individual energy. There has been some work on infrared solar cells. For example, see http://news.mit.edu/2012/infrared-photovoltaic-0621. See also https://en.wikipedia.org/wiki/Solar_cel ... olar_cells .
3. Do you have some other form of radiation in mind? E.g., RF/microwave radiation? Collecting charged particles in Jupiter's magnetosphere, perhaps?

[notFritzArgelander]

I was just watching the Weekly Space Hangout and they were talking about space probes using solar cells to save on plutonium. It got me to wondering why we don't have cell that can use other radiation. I heard that Jupiter puts out loads of radiation. Why can't we use that?

"Loads of radiation" is not specific enough. Not all radiation is equally useful.

For instance Jupiter's magnetosphere has a lot of ionizing radiation that damages electronics. It's high energy charged particles that causes device damage. With photons from the sun the energy is too low to ionize and cause damage but can be converted easily to electric power via the photoelectric effect.