Speaking for sokarul, a lot. There is no known means to provide the required propulsion. FE has yet another unanswered challenge.
A fan? Or what they use in space, I think they are ion thrusters? I haven't started reading about propulsion, but would these not work?
A fan, or more properly a propeller, requires an energy source. Carrying along fuel is a exercise in diminishing returns. Using sunlight fails both in terms of quantity and efficiency for propellers. Now ion technology is interesting but has no relevance here for two reasons. First, they still require a propellant, usually Xeon. Second, they fail to provide significant thrust. They're used in long-term in vacuo spaceflight.
So, no. these would not work.