An ion thruster would probably be the best way, although it still requires matter to shoot out the back. In any method, the solar power will only be used to pow

An ion thruster would probably be the best way, although it still requires matter to shoot out the back. In any method, the solar power will only be used to power whatever method you use to shoot matter out of the back. Because of this, you're still limited by the amount of fuel you can get into space at launch. http://en.wikipedia.org/wiki/Ion_thruster http://en.wikipedia.org/wiki/Ion_thruster