I was just reading an article about how the main factor preventing ion propulsion from being more effective is power generated from solar arrays. Solar arrays typically only generate 1-5 kW of power, which severely limits the thrust of ion thrusters. The article also predicted that if solar arrays could generate 100 kW, thrust would be on the order of pounds. Well lets say some magical device could efficiently and compactly generate 1000 kW. And then, 1 GW. Would thrust just keep rising and rising? Would it ever plateau?

  • $\begingroup$ There are engineering limits of how much power you can pump into a ion thruster before it melts. But there are no such limits on how many thrusters you can attach to a vessel in parallel. Also, higher power doesn't automatically mean better ISp. It may just mean that more propellant can be accelerated to the same speed, so you improve thrust but not delta-V. $\endgroup$ – SF. Feb 29 '16 at 17:06