A system (100, 200, 500, 600, 700) comprising: a prime mover (105, 205, 505, 605, 705) configured to rotate a shaft; and a wound rotor induction generator, WRIG, (110, 210, 510, 610, 710) comprising: a rotor (111, 211) coupled to the shaft of the prime mover (105, 205, 505, 605, 705) and configured to rotate when the shaft rotates, the rotor (111, 211) comprising a rotor winding (113, 213, 350, 450, 513); and a stator winding (112, 212a-212b, 300, 400, 420, 512a-512c, 612a-612c, 712a-712c) electrically connected to a utility source (130, 230, 530a-530b, 630a-630b, 730) and a load (160, 260, 560, 660); wherein: when the stator winding (112, 212a-212b, 300, 400, 420, 512a-512c, 612a-612c, 712a-712c) does not receive first power from the utility source (130, 230, 530a-530b, 630a-630b, 730), the WRIG (110, 210, 510, 610, 710) is configured to generate second power due to kinetic energy of the rotor (111, 211), and output at least a portion of the second power to the load (160, 260, 560, 660), characterized in that when the stator winding (112, 212a-212b, 300, 400, 420, 512a-512c, 612a-612c, 712a-712c) receives the first power from the utility source (130, 230, 530a-530b, 630a-630b, 730), the WRIG (110, 210, 510, 610, 710) is configured to transform at least one of a voltage and a frequency of the first power before outputting at least a portion of the first power to the load (160, 260, 560, 660). a prime mover (105, 205, 505, 605, 705) configured to rotate a shaft; and a wound rotor induction generator, WRIG, (110, 210, 510, 610, 710) comprising: a rotor (111, 211) coupled to the shaft of the prime mover (105, 205, 505, 605, 705) and configured to rotate when the shaft rotates, the rotor (111, 211) comprising a rotor winding (113, 213, 350, 450, 513); and a stator winding (112, 212a-212b, 300, 400, 420, 512a-512c, 612a-612c, 712a-712c) electrically connected to a utility source (130, 230, 530a-530b, 630a-630b, 730) and a load (160, 260, 560, 660); a rotor (111, 211) coupled to the shaft of the prime mover (105, 205, 505, 605, 705) and configured to rotate when the shaft rotates, the rotor (111, 211) comprising a rotor winding (113, 213, 350, 450, 513); and a stator winding (112, 212a-212b, 300, 400, 420, 512a-512c, 612a-612c, 712a-712c) electrically connected to a utility source (130, 230, 530a-530b, 630a-630b, 730) and a load (160, 260, 560, 660); wherein: when the stator winding (112, 212a-212b, 300, 400, 420, 512a-512c, 612a-612c, 712a-712c) does not receive first power from the utility source (130, 230, 530a-530b, 630a-630b, 730), the WRIG (110, 210, 510, 610, 710) is configured to generate second power due to kinetic energy of the rotor (111, 211), and output at least a portion of the second power to the load (160, 260, 560, 660), characterized in that when the stator winding (112, 212a-212b, 300, 400, 420, 512a-512c, 612a-612c, 712a-712c) receives the first power from the utility source (130, 230, 530a-530b, 630a-630b, 730), the WRIG (110, 210, 510, 610, 710) is configured to transform at least one of a voltage and a frequency of the first power before outputting at least a portion of the first power to the load (160, 260, 560, 660). when the stator winding (112, 212a-212b, 300, 400, 420, 512a-512c, 612a-612c, 712a-712c) does not receive first power from the utility source (130, 230, 530a-530b, 630a-630b, 730), the WRIG (110, 210, 510, 610, 710) is configured to generate second power due to kinetic energy of the rotor (111, 211), and output at least a portion of the second power to the load (160, 260, 560, 660), characterized in that when the stator winding (112, 212a-212b, 300, 400, 420, 512a-512c, 612a-612c, 712a-712c) receives the first power from the utility source (130, 230, 530a-530b, 630a-630b, 730), the WRIG (110, 210, 510, 610, 710) is configured to transform at least one of a voltage and a frequency of the first power before outputting at least a portion of the first power to the load (160, 260, 560, 660).