Why don’t we use ion thrusters?
The drawback of the low thrust is low acceleration because the mass of the electric power unit directly correlates with the amount of power. This low thrust makes ion thrusters unsuited for launching spacecraft into orbit, but effective for in-space propulsion over longer periods of time. Ion propulsion is not of value for missions that require high acceleration, and it often will not be worthwhile for missions that can be done quickly using conventional propulsion systems (such as missions to the moon).Unlike traditional chemical rocket engines, which have limitations on exhaust speed due to chemical reactions, ion engines can accelerate ions to significantly higher speeds—typically between 30 and 50 kilometers per second—allowing for much lower fuel consumption.
How efficient is ion propulsion?
Operating in the near vacuum of space, ion engines shoot out the propellant gas much faster than the jet of a chemical rocket. They therefore deliver about ten times as much thrust per kilogram of propellant used, making them very ‘fuel-efficient’. Drawbacks. Possibly the most significant challenge to the viability of plasma thrusters is the energy requirement. The VX-200 engine, for example, requires 200 kW electrical power to produce 5 N of thrust, or 40 kW/N.Unlike NASA’s space-based plasma thrusters, which operate in vacuum and produce low force, this technology is designed for the dense, demanding atmosphere of Earth.
What fuel do ion thrusters use?
The thrusters work by using an electrical charge to accelerate ions from xenon fuel to a speed 7-10 times that of chemical engines. The electrical power level and xenon fuel feed can be adjusted to throttle each engine up or down in thrust. The thrusters work by expelling charged atoms, or ions, of xenon, emitting a brilliant blue glow that trails behind the spacecraft.