Beam-powered Propulsion - Electric Propulsion

Electric Propulsion

Some proposed spacecraft propulsion mechanisms use power in the form of electricity. Usually these schemes assume either solar panels, or an on-board reactor. However, both power sources are heavy.

Beamed propulsion in the form of laser can be used to send power to a photovoltaic panel, for Laser electric propulsion. In this system, careful design of the panels is necessary as the extra power tends to cause a fall-off of the conversion efficiency due to heating effects.

A microwave beam could be used to send power to a rectenna, for microwave electric propulsion. Microwave broadcast power has been practically demonstrated several times (e.g. Goldstone, California in 1974), rectennas are potentially lightweight and can handle high power at high conversion efficiency. However, rectennas tend to need to be very large for a significant amount of power to be captured.