The world needs a new source of energy, an unspillable source.

new and possible space propulsion systems?

Is there any new form of space propulsion (besides ion drives,vasimr) currently being developed that could begin operation in the next 25 years or so to exceed the speed, efficiency, and range of the current space crafts that NASA and other space programs around the world use. Something that could perhaps reach the edge of the solar system within months and still be able the achieve greater distances.