Final project: The Martian Network
6. Power Supply
Satellites
The satellites have solar cells that provide power for all their essential functions. Their total area is 12 square meters (http://www.space-technology.com/projects/marsexpress/). Efficiency of the cells is expected to be around 10%, while the solar power density around Mars equals 0.6 kW/m2 . Hence, with perpendicular illumination the solar cells will yield 720 Watts of power. That should provide enough power for all circuits and for recharging the batteries that are necessary for operation in the periods when the solar energy does not reach the cells on the satellite.
Terminals on Mars
The terminals are equipped with solar cells as well as their main source of energy. The total area per terminal is about 2 square meters with amounts to 120 W of power when the production is at its peak. Since the terminals require much less transmit power than the satellites, that should suffice both for driving all the circuitry and for battery recharging as well.