A power plant capable of suppressing loss, and attaining downsizing and enhancement of mountability of the power plant. In the power plant T, the rotational speeds of third to first sun gears S3 to S1 and a carrier member 111 are in a collinear relationship with each other, and are sequentially aligned in the mentioned order in a collinear chart indicating the relationship between the rotational speeds. Further, the third sun gear S3 and the carrier member 111 are connected to first and second torque generators 113 and 114 capable of generating positive torque and negative torque, respectively, and the second and first sun gears S2 and S1 are connected to one and the other of two rotating shafts, respectively.