Black Hole Power 
One of the great challenges of today is to develop new sources of energy to power our civilization -- the Sun, wind, the oceans, and even life. For a civilization that had spread across the stars, though, the need for energy would require even more innovative thinking. It might harness the power of entire stars -- or the supermassive black holes at the centers of galaxies.
Scientists here on Earth have already envisioned several possible ways to get power from a black hole.
In one scenario, a spaceship would fly into the swirl of spacetime around the black hole and split apart. Half of the ship would fall into the black hole, while the other half would be thrown back into space. The escaping half would carry out much more energy than the whole spacecraft carried in. Our own spacecraft use similar techniques to “steal” energy from planets, boosting them to higher speeds.
In another scenario, superconducting coils could be built far outside a black hole to harness the energy of the black hole’s magnetic field.
Another idea was proposed just last year. Two scientists in Asia suggested that a ring of giant power stations could collect energy from the disk of superhot gas around the black hole, then beam it to worlds throughout the galaxy -- some of them thousands of light-years away. In fact, such a galactic power grid might even be detectable from here on Earth -- providing evidence of a civilization with really big light bills.
Script by Damond Benningfield, Copyright 2012