This paper highlights the increasing need for faster than real-time simulators of the electric power system and shows that microelectronic emulation is a very promising solution to overcoming speed problems of current numerical simulators. Research is focused on two different emulation approaches. Both of them are detailed in this paper and their electronic implementation is shown. Furthermore, the two approaches are compared and their final capabilities are depicted. By doing so, the paper shows that the two approaches are not competing; each one has its own advantages.