How to Extract Energy From a Black Hole

Spinning black holes have this weird effect on space time and also affects their event horizon. It can change the size of the event horizon if you spin your black hole or if you give it electric charge. So I think Freeman Dyson or maybe Roger Penrose came up with his plan to use black holes as a power source, which is pretty awesome. All we need to do is get really close to a black hole. Exactly.