Introduction to Solar Panels
Solar panel arrays will be the primary source of energy for the satellite, which is true for most satellites currently orbiting Earth. Photovoltaic cells are a perfect source of nearly endless energy, and in space, they are limited only by distance to a star. Although there are several other potential energy sources for satellites and probes, such a Radioisotope Thermal Generators, solar panels are the only source that can reach a level of output power in the high kilowatts. One reason for this is the high scalability. To increase the power output, one needs only to add additional solar panels, while the rest of the power system, such as the energy conversion and storage, remains largely the same.
The main limiting factor is the overall size of the solar panel array. A good areal power density is about 300 W/m2. Since this affects the size and geometry of the satellite, this has a significant impact on the ability to launch the satellite from Earth into space. There is also concern due to the fragile nature of most solar cell technologies, and larger panels may be more susceptible to damage. Weight of the solar panels is also a concern, but this is generally less significant due to a typical specific power of around 300 W/kg.