Well...."kinda-sorta". Hughes (now Boeing) invented the "XIPS" Xenon-Ion-Propulsion-System which uses electric power to produce a plasma from Xenon liquid. It's very efficient, but still relies on having a tank of *something* to use. Eventually, you run out of "stuff" to use, which renders an otherwise "good" satellite defunct. -- One man's Magic is another man's Engineering.
Well...."kinda-sorta". Hughes (now Boeing) invented the "XIPS" Xenon-Ion-Propulsion-System which uses electric power to produce a plasma from Xenon liquid. It's very efficient, but still relies on having a tank of *something* to use. Eventually, you run out of "stuff" to use, which renders an otherwise "good" satellite defunct.