An electric power-generating device with a rotor turned by an external source of energy, such as wind or water currents. The rotor is coupled to a main shaft. A pair of bull gears is located on the main shaft. A number of intermediate gears are located around a perimeter of the bull gears. An intermediate gear is connected to an input shaft having a double helix pinion that engages the pair of bull gears. The other intermediate gears are similarly connected to respective input shafts having double helix pimons that engage the pair of bull gears. A plurality of output shafts is provided. An output shaft has a single-helix output pinion that engages two adjacent intermediate gears. The other output shafts are similarly connected to respective adjacent intermediate gears. A number of rotational devices are connected to the output shafts.