NOVELTY - An electric power generation system (1) comprises: pair of water channel wall mutually arranged in parallel at intervals along the horizontal direction; and rotation unit (50) provided between a pair of the water channel walls. The rotation unit is for transmitting the energy of the flowing water to the electric power generation unit. The rotation unit rotates by the energy of the flowing water. The electric power generation unit produces electric power by driving the energy of the flowing water transmitted in the rotation unit in order to maintain speed or pressure of the flowing water.    USE - As power generation system (claimed) used in power plant.    ADVANTAGE - The power generation system provides quicker transformation of the energy of flowing water into electricity.    DETAILED DESCRIPTION - An electric power generation system (1) which transforms the energy of flowing water into electricity via an electric power generation unit comprises: pair of water channel wall mutually arranged in parallel at intervals along approximately the horizontal direction; and rotation unit (50) provided between a pair of the water channel walls. The rotation unit is for transmitting the energy of the flowing water to the electric power generation unit. The rotation unit rotates by the energy of the flowing water. The electric power generation unit produces electric power by driving the energy of the flowing water transmitted in the rotation unit in order to maintain the speed or pressure of the flowing water which flows through between a pair of the water channel walls. At least one of a pair of the water channel wall or the rotation unit was formed so that change of the mutual width of a pair of the water channel wall might be attained, or so that a movement was possible, and a change of the distance of at least one of a pair of the water channel wall and the rotation unit might be attained.    DESCRIPTION OF DRAWING(S) - The figure shows a top view showing the deformation condition of a floating body.    Electric power generation system (1)    Floating body (10a)    Water flow path (13)    Opening part (13a, 13b)    Rotation unit (50)    Shaft (51)