ABSTRACT
The traditional power system in space uses a solar array and battery for each satellite. The concept of using a centralized large power-satellite (powersat) has been receiving some seed funding at NASA for some time. In this concept, depicted in Figure 27.1, one high-power satellite would generate bulk power, which is then transmitted to multiple satellites by laser or microwave beams. The electric propulsion of spacecraft using beam power from a powersat was discussed in Section 23.8. The beam power can also be used for a rescue operation on a remote Earth surface or anywhere in the ocean. Advantages of the central power satellite transmitting beam power to multiple user spacecraft are:
Replaces PV array by much smaller power receiving antenna in the user spacecraft
Eliminates battery by proper orientation with the power satellite(s) that avoids satellite-to-satellite eclipse
Extends the mission life where the spacecraft life is solar array or battery limited
Provides large peak power if and when needed, such as for electric propulsion, thus significantly decreasing the on-board fuel mass
Orienting the spacecraft to the powersat beam may be simpler than orienting to the sun
The power generated by the powersat can be transmitted to user satellites in two ways: by a microwave beam or by a laser beam.
